Chapter 7: Cross Section Road Planning and Design Manual

Table of Contents
Acknowledgement 7-1
7.1 Introduction 7-1
7.1.1 General 7-1
7.1.2 Cross Section Determination 7-2
7.1.3 Terminology 7-2
7.2 Lanes 7-6

7
7.2.1 General 7-6
7.2.2 Two Lane Two Way Rural Roads 7-7
7.2.3 Multilane Rural Roads and Motorways 7-8
7.2.4 Urban Roads 7-8
7.2.5 National Highways 7-8
7.2.6 Bus Routes 7-8
7.2.7 Auxiliary Lanes 7-9
7.2.8 Parking Lanes 7-9
7.2.9 Turning Lanes/Turning Roadways and Ramps 7-10
7.2.10 Cycleways 7-11
7.2.11 Location of Kerb and/or Channels 7-12
7.2.12 Transit Lanes 7-12
7.3 Shoulders 7-20
7.3.1 General 7-20
7.3.2 Two Lane Two Way Rural Roads 7-20
7.3.3 Multilane Rural Roads and Motorways 7-21
7.3.4 Auxiliary Lanes 7-21
7.3.5 Ramps 7-21
7.3.6 Urban Roads 7-22
7.3.7 National Highways 7-22
7.3.8 Cycleways 7-22
7.3.9 Change in Shoulder Width 7-23
7.4 Medians 7-23
7.4.1 General 7-23
7.4.2 Rural Roads 7-23
7.4.3 Urban Roads 7-24
7.4.4 Motorways 7-26
7.4.5 Clearance to Medians 7-26
7.4.6 Rural Median Treatment 7-26
7.5 Verges, Footpaths and Outer Separators 7-27
7.5.1 Verges 7-27
7.5.2 Footpaths 7-27
7.5.3 Outer Separators 7-32
7.6 Clear Zone 7-36
7.6.1 General 7-36
7.6.2 Guidelines 7-36
7.7 Crossfall 7-36
7.7.1 General 7-36
7.7.2 Crossfall and Drainage 7-38
7.7.3 Road Crossfall 7-38
7.7.4 Median Crossfall 7-39

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Road Planning and Design Manual Chapter 7: Cross Section

7.7.5 Footpath Crossfall 7-39

7.7.6 Parking Lane Crossfall 7-39
7.7.7 Crossfall Configuration on Side Slopes 7-39
7.7.8 Split Level Carriageways 7-40
7.8 Batters 7-41
7.8.1 Batter Slopes 7-41
7.8.2 Traversable Batters and Batter Rounding 7-42
7.8.3 Batter Slope Treatment 7-43
7.8.4 Benches 7-43

7
7.8.5 Rock Fall Protection 7-48
7.9 Drainage 7-48
7.9.1 Table Drains 7-48
7.9.2 Catch Drains and Banks 7-48
7.9.3 Dykes 7-50
7.9.4 Batter Drains 7-50
7.9.5 Kerbs, Channels and Access Chambers 7-50
7.9.6 Floodways 7-51
7.10 Bridges and Clearances 7-53
7.10.1 Road Bridge Widths 7-53
7.10.2 Pedestrian/Cyclist Bridges 7-59
7.10.3 Lateral Clearance 7-59
7.10.4 Vertical Clearance 7-60
7.10.5 Pedestrian/Cyclist Subways 7-61
7.10.6 Clearance to Railways 7-61
7.10.7 Public Utility Plant 7-62
7.11 Special Considerations 7-62
7.11.1 Roads on Expansive Soils in Western Queensland 7-62
7.11.2 Roads in Rainforest (including Wet Tropics) 7-67
7.12 Typical Cross Sections 7-71
References 7-80
Relationship to Other Chapters 7-81
Appendix 7A: Template for Vehicle Clearance at Property Entrances 7-82
Appendix 7B:Multi-Combination Vehicles in Urban Areas 7-83

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 Chapter 7: Cross Section Road Planning and Design Manual

iv September 2004
Road Planning and Design Manual Chapter 7: Cross Section

Chapter 7 Amendments - September 2004

Revision Register

Issue/ Reference Description of Revision Authorised Date

Rev No. Section by
1 First Issue Steering Aug 2000
Committee

7
2 7.2.12 New section
7.5.2 Footpaths and Driveways - modification to W. Semple Jan 2001
2nd paragraph
3 7.2.8 Modification to 1st paragraph W. Semple Feb 2001
7.10.1 Table 7.18 - modification to notes
4 7.1.3 Additional definition
7.2.4 Modifications. Table 7.5 removed
7.2.6 Modifications
7.2.8 Modifications
7.2.10 Modifications
7.2.11 Additional dot point
7.5.2 Additions
7.7.3 Additional subsection Steering July
7.7.5 ‘Sight impaired’ changed to ‘visually impaired’. Committee 2001
7.7.6 Additional subsection
7.9.2 Figure 7.20 modified. Additions to 3rd paragraph
7.9.5 Modifications and additions. Figure 7.21 modified
7.9.6 New
7.10.1 Additional 2nd paragraph
7.10.2 Modifications to 1st paragraph re min. vertical clearance
7.10.4 Modifications to Table 7.21
7.10.5 Additional paragraph
New Relationship to other chapters
5 7.2.1 Diagram renumbered as Figure 7.2.1 and referenced in text
7.2.12 New subsection “Enforcement”. Modifications to Figures
7.2.12.5 to 7.2.12.8
7.4.2 Additional text after 3rd paragraph
7.4.6 Additional text at the end of 1st paragraph
7.5.2 Modifications to Figures 7.7 Steering May
7.9.5 Additional text at the beginning of subsection Committee 2002
7.10.1 Additional text after 3rd paragraph
7.10.2 Additional text
7.10.7 Modifications to Table 7.22
7.12 Modifications to Figures 7.27 to 7.29 and 7.32
App. 7A Modifications to diagram
6 7.3.9 New section - “Change in Shoulder Width” Steering July
7.4.3 Additional text - “Tips for treatment of urban medians” Committee 2002
7.7.3 Additional text - limits on crossfall for turning roadways
7 7.2.4 Inclusion of Chapter no. for reference
7.2.8 Additional text “Parking restrictions at intersections” Steering Sep
7.2.11 Correction of section reference number Committee 2004
7.2.12 Additional text - “Transit Lanes - Enforcement”

September 2004 v
 Chapter 7: Cross Section Road Planning and Design Manual

Issue/ Reference Description of Revision Authorised Date

Rev No. Section by
7 7.3.1 Correction of table reference number Steering Sep
7.4.3 Additional text - “Urban Roads - Tips for treatment of Committee 2004
urban medians”
7.4.3 Correction of typical/cross sections reference number
7.4.5 Correction to kerb type reference numbers
7.4.6 Spelling correction
7.4.6 Correction to Typical Cross Section reference number

7
7.5 Modifications to Fig 7.7
7.5.2 Correction to text
7.5.2 Additional text
7.5.2 Removal of reference to Fig 7.14
7.5.2 Move text
7.6 Additional symbol on Fig 7.12
7.6.2 Additional text
7.7.1 Spelling correction
7.7.3 Additional text - inclusion of Chapter no. for reference
7.7 Additional text as 7.7.6
7.7.6 Renumbered to 7.7.7
7.7.7 Renumbered to 7.7.8
7.8 Modification to Fig 7.18(b) - spelling error
7.9.1 Correction to kerb type numbers
7.9.5 Change of Table 7.9.6 to Table 7.16
7.9 Fig 7.21 - correction of dimension in type 3 kerb
7.9 Fig 7.21 - Additional note for kerb type 25/26
7.9 Fig 7.21 - Additional note for kerb type 18/19/20/21
7.9 Fig 7.21 - Removal of kerb types 28 and 29
7.9 Fig 7.21 - Rename kerb type 30 to type 28
7.9.6 Amendment to table number - “Width Range”
7.9.6 Removal of text - “Width Range”
7.10.7 Correction to Section number reference
7.11.2 Correction to text
7.12 Additional text
Fig 7.27 Additional note and symbol
Fig 7.28 Additional note and symbol
Fig 7.29 Additional note and symbol, width correction
Fig 7.30 Additional note and symbol
Fig 7.31(a) Additional note and symbol
Fig 7.31(b) Additional note and symbol
Fig 7.32(a) Modifications to diagram
Fig 7.32(a) Change to channel type
Fig 7.32(b) Modifications to diagram
Fig 7.32(b) Change to channel type
References Additional references included

vi September 2004
Road Planning and Design Manual Chapter 7: Cross Section

Chapter 7
Cross Section
Acknowledgement occurs. For instance, decisions on shoulder width
can only logically be made in the light of the
This Chapter is based on the Roads and Traffic available sight distance due to vertical and
Authority of NSW Road Design Guide Section 3 - horizontal alignments, the pavement surface

7
Cross Section. Details of the elements in the treatment, adjoining travel lane widths and
Chapter have been modified to suit Queensland predicted traffic volumes and composition. (See
practice and conditions, but the structure of the also Chapter 10 for coordination with alignment
Chapter and much of the text has been adopted design). A holistic approach has to be taken to the
from the RTA Guide. The assistance of RTA in design and the cross section has to be designed in
developing this Chapter is gratefully conjunction with the landscape elements (refer
acknowledged. Road Landscape Manual, Main Roads 1998).

Relative Costs
7.1 Introduction
For most works the cost of providing the
7.1.1 General pavement, and its wearing surface, is the most
significant factor in the total cost of a road project.
The cross section of a road is a vertical plane, at It is therefore important to ensure that the width of
right angles to the road control line, viewed in the pavement adopted is the appropriate one for the
direction of increasing chainage, showing the circumstances. Because pavement materials are
various elements that make up the road’s expensive, small increases in the width of lanes
structure. A cross section can show transverse and shoulders can add significantly to the total
detail from boundary to boundary, detailing the cost of the project, even if the percentage increase
various road components. is relatively small.

The aim of a cross section is to show variations Particular care is needed in cases where
within the design and its interaction with the improvements are being made to roads on the
natural topography. A design should be existing formation. Adopting dimensions that will
sympathetic to the natural environment and user require widening of the formation will cause a
expectations, while maintaining a balance large increase in the cost of the work. However,
between construction, maintenance and operating once established on a project, marginal increases
(including accident) costs. in dimensions may not represent a significant
increase in the total cost.
The major elements of a road cross section are
illustrated in Figure 7.1. More extensive details Designers should examine the cost of alternatives
are shown in Section 7.11. to ensure that the most cost effective solution is
adopted.
Three factors are fundamental to the use of this
section of the Road Planning and Design Manual: Clear Zones

The Total Package Vehicles run off the road; hence shoulder, verge
and batter design must make provision for a clear
The elements comprising a cross section form part zone (see Figure 7.1) which will allow an errant
of a package; accordingly, decisions about the vehicle to traverse this area, sustaining minimum
dimensions to be adopted for an individual damage to itself and occupants (see also Sections
element must recognise the considerable degree 7.5 and 7.6).
of inter-dependence of design considerations that

September 2004 7-1

 Chapter 7: Cross Section Road Planning and Design Manual

The clear zone concept underlines the fact that a 7.1.2 Cross Section
reasonably flat, well compacted and unobstructed Determination
road side environment is highly desirable,
especially on high travel speed roads. The Flow Chart given as Figure 7.2 details the
procedure to undertake in determining the most
Urban areas have specific problems created by appropriate cross section to be adopted.
utility poles. However, efforts should still be References to other sections of the Road Planning
made to ensure that the appropriate speed related and Design Manual are given for assistance.
clear zone is provided, especially on new

7
construction. In urban areas, footpaths will
provide an adequate clear zone, provided utility 7.1.3 Terminology
poles, sign supports and heavy structures are kept
to the rear of the footway, or made frangible, and A.A.D.T.
all planting consists of frangible species. Total yearly traffic volume in both directions,
Undergrounding of Public Utility Plant will assist divided by the number of days in the year gives
in keeping the footpath clear. the Annual Average Daily Traffic volume.

Auxiliary Lane
Clear Zone Travelled Way
A portion of carriageway adjoining through
Batter Verge Shoulder Lane
traffic lanes, used to separate either faster
overtaking traffic or slower moving vehicles
from through traffic, or for other purposes
supplementary to through traffic movement.
Embankment
Batter
Clear Zone Travelled Way This is the uniform side slope of a cutting or an
Batter Verge Shoulder Lane embankment, expressed as a ratio of 1 unit
vertical on X units horizontal.

Batter Drain
Cutting A lined open drain for removing stormwater
from the top to the toe of the batter in order to
reduce scour of the batter face.

Batter Rounding
Clear Zone Travelled Way
Curvature that is applied to improve the
Footway
*
Lanes stability and appearance of the road at the
intersection of the extension of the road
crossfall and/or existing surface (hinge point),
with the batter slope of an embankment or
Urban Areas cutting.
* Width of Channel
Bench
Figure 7.1 Typical Clear Zone This is a ledge that is constructed on a batter or
natural slope for the purpose of providing
adequate horizontal sight distance, greater
security against batter slippage or to assist with
batter drainage.

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Road Planning and Design Manual Chapter 7: Cross Section

YES Adopt National

Is the project on a National-Highway?
Highway standards
NO for lane and shoulder
Collect Data: Traffic volumes, Traffic composition, widths
proposed speed zone, max. grade, See 7.2.5. And 7.3.7
horizontal alignment, accident history, etc.

Consider warrants for Auxiliary lanes, Medians, Separated carriageways, Cycleways, etc.

7
YES Is the formation width known? NO
(Median + lanes + shoulders + verges)

Ascertain number of lanes and widths Ascertain the minimum

required for the predicted design traffic volume lane width. See 7.2

Calculate the effective

lane width. See 7.2

NO Determine the minimum lane widening

Does this satisfy minimum lane width values?
required.
YES See Chapter 11 - Horizontal Alignment.
Determine the minimum lane widening
required. See Chapter II- Horizontal Alignment.

Determine appropriate shoulder widths. See 7.3

Consider warrants for Lay bys, emergency

phone bays, bus stops, inspection bays etc.

Determine batter slopes according to Geotechnical data, stabilisation treatment,

maintenance, environmental and aestetic values

Are batter slopes flatter NO Consider safety barrier

than 1 on 3 possible? installation.
YES
What is the appropriate clear zone Is additional width required
NO
according to design speed and batter behind the barrier or terminal
configuration. See 7.6 to accommodate deflection?
YES
Apply rounding for traversable or Adjust the formation width to
recoverable batter slopes See 7.8.3 accommodate deflection of
the proposed barrier

Determine appropriate treatment for ALL Adjust the cross section elements to
hazards within the clear zone. accommodate the required
See Chapter 8 - Safety Barriers and stabilisation, landscaping, drainage
Roadside Furniture environmental treatments

YES Does the adjusted construction

width still fit within road reserve?
NO
Can the batter slope/s be adjusted to fit YES
construction width within the road reserve
considering all requirements
NO
Prepare plans for the acquisition
of additional land
Figure 7.2 Cross Section Determination

September 2004 7-3

 Chapter 7: Cross Section Road Planning and Design Manual

Berm due to tracking, steering inaccuracies and

A ledge formed at the bottom of an earth slope vehicle slippage.
or at some level intermediate between the
Cycleway
bottom and the top.
A separate path or a portion of the road (either
Capacity shared or exclusive) allotted to the use of
The maximum rate of flow at which vehicles cyclists.
can traverse a point or segment of a lane or
Declared Road
roadway during a specified time under

7
prevailing roadway and traffic conditions, Any road in the State of Queensland declared to
expressed as vehicles per hour. be a road under the control of the state under
the Transport Infrastructure Act 1994.
Carriageway
Design Speed
That portion of the road formation, including
lanes, auxiliary lanes and shoulders that is set A nominal speed adopted for the design of the
aside for the use of vehicles, either moving or geometric features of the road.
stationary.
Dyke
Catch Bank A low embankment of earth, asphalt or
A small catch levee constructed along the high concrete placed near the edge of embankments
side of a cutting to intercept and direct the flow to control water movement.
of surface water.
Effective Lane Width
Catch Drain This is the dimension of a lane that is measured
A surface channel constructed along the high from the centre of a lane line to the centre of a
side of a road or embankment outside the batter lane line or from the centre of a lane line to the
to intercept surface water. face of the kerb.

Clear Zone Footpath

This is the border area that begins at the edge of This area is located between the face of the
each travelled lane and is available for kerb and the property boundary for use by
emergency use by errant vehicles who run off pedestrian traffic, possible bicycle traffic and
the road. This zone includes any adjoining also for the placement of utility services.
lane/s, road shoulder, verge and batter.
Footway
Crossfall A pedestrian facility on a bridge.
Expressed as a percentage, this is the cross
Hinge Point
slope of the road surface at right angles to the
road alignment. (Applied for pavement The point where the extended crossfall of the
drainage.) verge area meets with the batter slope. This
point is associated with rounding where it is
Cross Section applied.
A vertical view made at right angles to the
Lane
control line, showing the natural ground and
the various elements that make up the road’s Part of the roadway set aside for the normal
structure. movement of a single stream of vehicles.

Curve Widening Lay Bys

Widening is applied, additional to the normal Lay bys are short lengths of widened, sealed
lane width on some curves. This additional shoulder that is provided for the purpose of
width caters for widths of the turning vehicle vehicles to stand clear of the carriageway.

7-4 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Median Split Level Carriageways

The central strip of road not intended for use by Two similarly aligned, separated, and
traffic, which separates opposing traffic flows. independently graded carriageways.
Median width includes both adjacent shoulders.
Superelevation
Median Cross-over The continuous transverse slope normally
A sealed section of roadway that is provided given to the carriageway at horizontal curves.
between separated carriageways for the
purpose of allowing cross-median movements Table Drain

7
(often for emergency vehicles). The drain (lined or unlined) that is located
adjacent to the shoulder of the road in cutting,
National Highway
usually having an invert lower than the sub-
High speed route linking the Nation’s State grade level, and formed as part of the
capital cities and major provincial centres, as formation.
detailed under the National Highway Act of
1986. Terrain
The shape of the natural landscape surrounding
Nearside
a road, broadly classified as follows-
This is the left hand or kerb side of a vehicle,
relative to the direction of travel. • Easy relatively level terrain, large horizontal
radii joined by long straights with cuttings
Offside and embankments on average 2m high, with
This is the right hand or median side of a road grades up to 2.5%.
vehicle, relative to the direction of travel. • Average rolling terrain, with cuttings and
embankments that are on average 5m high,
Outer Separator with road grades up to 5%.
This is the portion of road reserve that separates • Difficult mountainous terrain, minimum
a through carriageway from a service or horizontal radii, where climbing lanes may
frontage road. be required, with cuttings and embankments
Parking Lane greater than 10m high and road grades
steeper than 5%.
Lane primarily used for vehicle parking.
Travelled Way
Service Road
A subsidiary carriageway that is constructed The portion of the carriageway that is assigned
between the principal carriageway and the to moving traffic, excluding shoulders and
property line, and connected only at selected parking lanes.
points with the principal carriageway. Traversable Batter
Shoulder A batter offering errant vehicles safe travel
A shoulder is that portion of the carriageway, during a run-off-the-road incident, bringing the
measured from the outside edge of the outer vehicle to rest in an upright position.
traffic lane, adjacent to and flush with the
Turning Lane
surface of the traffic lane. The shoulder
excludes any berm, verge, rounding or extra An auxiliary lane reserved for turning traffic.
width that is provided for the installation of
Verge
sign posts, guide posts or safety barriers.
The area located between the outer edge of the
Shy Line shoulder and the batter hinge point, used for the
This is the offset to a hazard that a driver purpose of providing drainage, safety barriers
perceives to be adequate for his current travel and rounding.
speed adjacent to that hazard.

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 Chapter 7: Cross Section Road Planning and Design Manual

7.2 Lanes Table 7.1 Shy Line Distances

85th Percentile Shy Line Distance (m)

7.2.1 General Speed (km/h) Nearside Offside
(Left) (Right)
The traffic lane is that part of the roadway set ≤70 1.5 1.0
aside for the normal one way movement of a 80 2.0 1.0
single stream of vehicles. 90 2.5 1.5
≥100 3.0 2.0
Traffic lanes carry out a variety of functions

7
important to the overall efficient function of the
road hierarchy:
Depending on the lane configuration and the road
• through road; alignment, a reduction in lane width/s reduces the
• rural or urban; lateral clearance between vehicles leading to
• special - bus, transit etc.; reduced travel speed and lane capacity. Tables 7.2
and 7.3 show lane capacity reductions according
• auxiliary (turning or overtaking);
to clearances from lateral fixed hazards.
• parking;
• cycleways.
Table 7.2 Two Lane Roadway
Both the lane width and the road surface condition
Lane Capacity
have a substantial influence on the safety and
Clearance (% capacity of 3.5m lane)
comfort of users of the roadway. In rural
3.5m 3.3m 3.0m 2.7m
applications, the additional costs that will be lane lane lane lane
incurred in providing wider lanes, will be partially 1.8 100 93 84 70
offset by the reduction in long term shoulder 1.2 92 85 77 65
maintenance costs. Narrow lanes result in a 0.6 81 75 68 57
greater number of wheel concentrations in the 0.0 70 65 58 49
vicinity of the pavement edge and will also force
vehicles to travel laterally closer to one another
than would normally happen at that design speed. Table 7.3 Four Lane Undivided Roadway

Drivers tend to reduce their travel speed, or shift Lane Capacity

closer to the lane/road centre (or both) when there Clearance (% capacity of 3.5m lane)
is a perception that a fixed hazardous object is too 3.5m 3.3m 3.0m 2.7m
close to the nearside or offside of the vehicle. lane lane lane lane
When there is a perceived fixed hazard there is a 1.8 100 95 89 77
movement by the vehicle towards the opposite 1.2 98 94 88 76
lane line. The offset of this fixed hazard from the 0.6 95 92 86 75
edge of the lane where this reaction starts to be 0.0 88 85 80 70
observed is called the “Shy Line”.

The shy line is taken as the distance from the edge The widths of all lanes adjacent to kerblines
of travelled lane to the outer edge of shoulder, exclude the width of the channel.
provided that there is a significant length of
constant width shoulder in advance, or as the It must be remembered that the legal width limit
distance as shown in Table 7.1, whichever is the of commercial vehicles is 2.5m. The majority of
greater. heavy vehicles are built to this maximum width,
BUT it does not include the additional 200 mm
width on each side of the vehicle generated by
wing mirrors.

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Road Planning and Design Manual Chapter 7: Cross Section

Widths (m)

Prime Mover/Semi Trailer (19m)

Truck/Trailer (R12T12)

Truck/Trailer (R12T22)

A-Double (Type1 road train)

60km/h
60kmh
A-Triple (Type 2 road train)
90km/h
90kmh
19m B-double

7
25m B-double

B-Triple

Rigid +3 (Not Permitted in Qld)

0 0.5 1 1.5 2 2.5 3 3.5 4

Figure 7.2.1 Minimum Estimated Vehicle Path

ARRB Transport Research was commissioned to 7.2.2 Two Lane Two Way Rural
develop minimum estimated lane width Roads
requirements for various heavy vehicles. Data
from this study is presented in the histogram Minimum traffic lane widths for two lane two way
“Minimum Estimated Vehicle Path” (Figure rural road applications should be determined from
7.2.1). Table 7.4.

This figure does not include a clearance Where the intended design speed through
component. Typically an additional 0.5m is added mountainous terrain will be in excess of 80 km/h,
to the given widths to determine the lane width. or 100 km/h in undulating terrain, or where there
is a predominantly high percentage of heavy
These minimum vehicle path width values are vehicles (20% for 500 AADT and 5% for 2000
based on straight travel, a road roughness of 120 AADT), a lane width of 3.5 m is desirable.
counts/km (NAASRA), average crossfall of 4.5%
and two test speeds. This particular combination Refer to Section 7.2.1 for discussion on various
would be regarded as too extreme for typical heavy vehicles.
situations, but no other data is available at present.
Furthermore, a different set of test conditions
would need to be considered for roads with Table 7.4 Guidelines for Traffic Lane Width (Two
Lane Rural Roads)
geometry other than straight paths.
Width of Anticipated AADT at Opening
The research suggests that most vehicles, with the Traffic Low Reasonable High
exception of Type 2 road trains or rigid truck plus Lanes Future Future Future
Growth Growth Growth
3 trailers, could comfortably operate along roads (<3)% (3-6)% (>6)%
that have a usable lane width of 3.5m, in a speed Two Lanes (6.0) up to 700 up to 500 up to 300
environment of 90km/h. The operating speed for (6.5) 700-1700 500-1200 300-900
Type 2 road trains is 80km/h, therefore some (7.0)* over 1700 over 1200 over 900
reduction of road width requirement from those * Where local conditions dictate, widths in excess of
given could be expected. Generally, past 7.0m may be considered.
performance suggests that Type 2 road trains can If in using the table, volumes fall near the boundary of
operate adequately in 3.5m lanes with 1m sealed groups, consider carefully whether to use higher or
lower value.
shoulders on straights with 3% crossfall.

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 Chapter 7: Cross Section Road Planning and Design Manual

7.2.3 Multilane Rural Roads and • Straight 3.1m for kerbside lanes; 3.0m
Motorways Alignment for other lanes
• Curved widening in accordance with
The lane widths provided on multilane rural roads Alignment Table 11.8 of “Chapter 11:
should be 3.5m. Desirably any rural road Horizontal Alignment” should
consisting of four lanes or more should have a be applied.
central median, separating opposing traffic flows.
Where lanes are adjacent to barrier kerbs, it is
The normal lane width on Motorways is 3.5m. desirable to locate the kerb at least 0.5m from the

7
Where a one-way carriageway is three lanes or edge of the lane to compensate for the tendency of
more, the central lane/s should be 3.7m (see the driver to shy away from the kerb. Usually, the
Figure 7.32). width of the channel is satisfactory for this
purpose.

7.2.4 Urban Roads For routes accommodating multicombination

vehicles (MCV), allowance has to be made for the
It is desirable for traffic lanes on urban roads to be size of vehicles and their tracking characteristics.
3.5 m wide but if the road reserve is restricted or Appendix B sets out the minimum requirements
an on-road bicycle lane is required, the lane for these routes.
width/s may be reduced.

Quite often the designer is faced with the task of

“squeezing” an extra lane or bike lane from an
existing or partially widened road formation. It
has been observed in the Netherlands that where
bicycles are mixed with general traffic, either
narrow (3.0 to 3.3m) or wide (3.7 to 4.0m) lanes
should be used. Intermediate widths (3.5m) tend Figure 7.3 Lane Width Notation
to be wide enough to encourage cars to pass
bicycles, but not wide enough to do so safely.
Where bicycles are to be accommodated in the 7.2.5 National Highways
kerb lane, the wider lanes are preferred.
National Highway design should provide a
To allocate lane widths on an equitable basis, the
consistent design form, enhancing a high speed
differing functions and interfaces of each lane
environment in an aesthetically pleasing
needs to be taken into account.
surrounding. The width of all lanes shall be not
It should be noted that “effective” lane widths are less than 3.5m.
measured from the centreline of linemarking or
from the face of the kerb. See Figure 7.3.
7.2.6 Bus Routes
The restrictions encountered will often require
lane widths to be reduced to fit the required • New construction on roads with bus routes
number of lanes into the available space. These should provide for a desirable kerb lane width
widths can be as low as 3.0m and can vary up to of 3.7m and a minimum of 3.3m except where
the desired width of 3.5m. The minimum lane the bus route forms part of the cycle network in
widths to be adopted are as follows: which case the minimum kerb lane width will
be 4.1m. It may be necessary to take width off
other traffic lanes to allow for this.
Alternatively, a suitable bicycle route can be
dedicated in the same corridor. (Note that buses
in Brisbane City occupy 3.15m when mirrors

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Road Planning and Design Manual Chapter 7: Cross Section

are included.) 7.2.8 Parking Lanes

• On existing roads with bus routes the following Parking Lanes adjacent to urban roads are normal
conditions apply: practice. In rural situations, parking lanes are not
1. Kerbside lanes to be marked not less than provided but some provision for parking at rest
3.0m width, from the face of the kerb. stops and motorist stopping places may be made -
Where the lane widths are 3.0 m or less, the see Chapter 20 for these cases.
kerbside lane should be marked wider than
the adjacent lanes to offset the effects of In urban roads, the parking lane often fulfils the

7
kerbs, channels, power poles and other function of a shoulder as discussed in Section 7.3
roadside structures. but its use is predicated on traffic and service
grounds exclusively. It is useful to consider the
2. Site specific measures to mitigate the effect functions of various types of urban roads to put the
of the narrow lane should be investigated. decision on the cross section required in context.
These include parking restrictions, median
adjustments, indented bus bays and so on. Major Routes - Single Purpose

3. Discussions should be held with the These comprise the through pavements of limited
appropriate Queensland Transport Manager access routes and urban motorways. The road
or private bus operator during the planning caters for moving traffic and occasional stops and
stage to ensure that arrangements are the design parameters are similar to those of rural
acceptable. roads. Traffic lanes and shoulders are provided
and rural forms of cross section are acceptable.
(See “Guide to Traffic Engineering Practice - Part
Parking is not an issue other than providing for
11, Parking” (Austroads, 1995b), for bus bays.)
stopped vehicles (broken down, fatigue etc.).

7.2.7 Auxiliary Lanes Major Routes - Mixed Purpose

These form the bulk of major urban traffic routes.

For auxiliary lanes other than parking and turning
They carry frontage development and hence cater
lanes, the lane width should be the same as the
for access movements, parked vehicles and
adjoining lanes (see Chapter 15, Auxiliary Lanes).
parking and unparking of those vehicles as well as
Auxiliary Lanes located on steep grades are to be for moving traffic. Design principles differ from
provided on the offside where analysis shows that those of rural roads. Cross sections include traffic
they will be cost effective. (See Chapter 15.) lanes, bicycle lanes and parking lanes (often
serving the function of shoulders).
The configuration will require drivers of
overtaking vehicles to move to the right, out of the Local Access Roads
nearside lane. Overtaking vehicles will move to
the offside lane, returning to the nearside lane The principal design factors relate to property
after completing the overtaking manoeuvre. An access, property drainage and width between
emergency runoff (sealed hard stand at least 3.0 m kerbs. Providing for parked vehicles within the
wide) is to be provided on the nearside at the end cross section is important.
of the merge (see Figure 15.6, Chapter 15).
Frontage/Service Roads
On some grades, short passing bays are
These roads are not a separate class but may be
sometimes placed on the nearside of the through
either local access or mixed purpose roads. The
lane to allow slow vehicles to pull over. The width
lowest class of service road provides only for
is to be the same as the adjacent lane. (See
local access (residential access, industrial
Chapter 15 for details.)
development, and shopping centres). On major
urban corridors in large cities, they can eventually

September 2004 7-9

 Chapter 7: Cross Section Road Planning and Design Manual

carry significant proportions of traffic other than lane combination as this is where most of the
for local access purposes. “frictions” occur. This applies principally to
suburban shopping/business areas on arterial
As the through significance of the main pavement roads. In these cases, as speeds tend to be slowed
of the service road increases, there is a tendency there is merit in reducing through lane widths and
for fewer connections to the rest of the street using minimum median width between
system. In these cases, the service roads tend to a intersections to obtain this additional space.
mixed function status with increasing importance
given to other than local accessing traffic. They Where angle parking is adopted, the width and

7
can ultimately become arterial/collector roads in markings defined in the Manual of Uniform
their own right. Traffic Control Devices should be adopted.

Widths Parking restrictions at intersections

An exclusive parallel parking lane should be a Parking should be designed so as not to interfere
minimum of 2.5m wide. If a kerb and channel is with sight distance or impede the flow of traffic
provided on the road, the width of the channel turning at an intersection. Regulations prohibit
may be used as part of this minimum width parking within certain distances from the cross
although this is undesirable. This minimum width road property boundaries.
should only be used in situations where there is no
likelihood of the lane being required for traffic Table 7.5 indicates the distances over which
purposes in the future and the reduced capacity of parking is prohibited at an intersection. Distances
the road produced by this arrangement is adequate given are for both signalised and non-signalised
for the traffic volumes expected. intersections.

A parallel parking lane used as a travel lane during

peak times, should be the same width as normal 7.2.9 Turning Lanes/Turning
urban travel lanes, namely a desirable width of 3.5 Roadways and Ramps
m and a minimum of 3.0 m to the lip at the
channel. Where bicycles are to use the kerb lane, The desirable width for turning lanes is 3.2 - 3.5m
the desirable minimum width is 3.7m, but a width with a minimum width of 3.0m. The width of right
of 3.5m should be avoided (see 7.2.4). turn storage lanes should be determined in
conjunction with median widths. See Chapter 13,
Shared parallel parking and traffic lanes should be Intersections at Grade.
5.5m wide (3.5 travel lane + 2.0 parking lane to
the channel lip) and an additional 1.0 - 1.5m One lane ramps at the interchanges are generally
where there is a shared bicycle and parking lane. 4.0m wide. If two or more lanes are required, the
(Refer to Austroads, 1995b and Chapter 5.) This is width of the lanes is to be 3.5m (see Chapter 16).
the borderline between acceptable and difficult
operation.

In areas where frequent parking is combined with

reasonable arterial volumes there is merit in
putting all spare width into the outer lane/parking

Table 7.5 Distances over which Parking is Prohibited at an Intersection

Non-signalised Intersections Signalised - Major Roads Signalised - Other

Approach Depart Approach Depart Approach Depart
Parallel Parking 6.0 m 6.0 m
100.0 m 100.0 m 30.0 m 15.0 m
Angle Parking 12.0 m 9.0 m

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Road Planning and Design Manual Chapter 7: Cross Section

7.2.10 Cycleways Figure 7.4 shows the lateral forces which are
applied to cyclists when in close proximity to
Where bicycle lanes are provided on routes, heavy vehicles travelling at speed.
appropriate widths for shared and exclusive
bicycle lanes are given in Chapter 5, which have Lane widths that may result in a squeeze point for
been derived from “Guide to Traffic Engineering cyclists should be avoided if possible. On left
Practice, Part 14 - Bicycles” (Austroads, 1999). hand curves, parked cars tend to “truncate” the
See Table 7.6. Exclusive lanes are preferred where corner and use up space allocated to cycles in a
space is available. shared lane. Restriction of parking in these

7
circumstances should be considered.

Cyclists have a legitimate claim to use public

Table 7.6 On Road Bicycle Lane Widths
roads and provision is to be made for them. They
Speed Facility Lane Width can be on or off the carriageway (i.e. elsewhere
(km/h) (m) within the road reserve or on a separate route). On
60 Exclusive lane 1.5 motorways, cycleways must be separate from the
80 Exclusive lane 2.0 carriageway as required by the motorway
100 Exclusive lane 2.5 legislation.
60 Shared with parking lane 4.0*
80 Shared with parking lane 4.5 Elements constructed on the path provided for
cyclists are to be designed on the basis that
* 4.5m preferred to allow cyclists to avoid opening bicycles will have tyres that are a minimum of 20
doors on parked cars.
mm wide (e.g. bicycle safe grates).

Note: Lateral forces may be increased where enclosed roadways (e.g. under bridges) create a “wind tunnel” effect.
In these cases, it may be appropriate to encourage cyclists to use the footpath (fencing, signage) to increase the
separation distance.

Figure 7.4 Lateral Forces on Cyclists, Induced by Heavy Vehicles

September 2004 7-11

 Chapter 7: Cross Section Road Planning and Design Manual

Adjoining furniture is to be free from protrusions • Bus stops should be placed on the more
that may snag the clothing of cyclists, or cause efficient far side or mid-block locations;
unnecessary injury in a fall.
• Designs must accommodate left-turning
Where a safety barrier is erected and there is a general purpose vehicles without impeding the
warrant to provide additional protection to flow of through High Occupancy Vehicles
prevent cyclists suffering injuries from falling (HOVs);
over the top of the barrier (such as on bridges with
drops of more than five metres), a 75 mm (min.) • Queue jumps must be sufficiently long to be
practical and must be effectively signed;

7
diameter rail 1400 mm high is to be provided on
top of the concrete barrier. The rail must not have
• Priority lane signage and pavement marking
potential to spear an impacting vehicle. It is not
should be substantially enhanced and designed
required where the height of the safety barrier is
for high impact;
1200 mm or higher.
• Design should support enforcement and must
Where the cycleway is adjacent to guardrail in
be developed in consultation with the Police;
these conditions, a weld mesh fence 1400mm high
should be placed behind the guardrail. • The needs of bicyclists should be fully
addressed and the synergies between the often-
overlapping priority rules for cycling and
7.2.11 Location of Kerb and/or HOVs should be captured; and
Channels
• Transit lanes should be implemented within the
In general, kerbs should be avoided in high speed context of a network strategy or framework to
environments. Where they are used, kerb and/or ensure that they contribute to a treatment long
kerb and channel are located outside the travel enough to create sufficient time savings to
lanes on both the nearside and offside of the road. induce modal shift and encourage car-pooling.
A 1.0m offset to the kerb face shall be provided
when the design speed is > 80km/h. If the design Alternative Treatments
speed is < 80km/h, an offset of 0.5m is permitted
in unlit situations with 0.0 m offset permitted in lit Providing priority treatment for HOVs is not a
areas. (See Section 7.4.5). new concept, nor does it necessarily involve
radical or unconventional changes to the street
system. It can be as simple as putting up some
7.2.12 Transit Lanes signs designating a certain lane for bus use only
during specified hours.
Transit lanes are discussed in some detail in
Chapter 2. This Chapter deals with the physical For each case, alternatives are grouped in three
layout of various treatments and appropriate categories:
dimensions for components. • segment treatments;
Design Principles • intersection treatments; and
• Transit lanes should be accompanied by • spot treatments.
indented bus bays, so through traffic (including
express buses) and emergency vehicles can There is some overlap, and a single corridor could
avoid being trapped behind a stopped bus; conceivably use several different treatments over
its length, but each alternative can be identified
• Signal phasing needs to be designed to ensure and illustrated as a stand-alone option at this
that bus drivers do not avoid bus queue jump stage. The “do nothing” and “improve general-
lanes (advance green light for buses) in favour purpose traffic” options also need to be included
of using the general purpose lanes; when assessing alternatives at the corridor level.

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Road Planning and Design Manual Chapter 7: Cross Section

The alternatives are listed below, and are chapter. Some compromise may sometimes be
illustrated in Figures 7.2.12.1 to 7.2.12.4. (No required to accommodate the limited space
distinction is made between use as a T2, T3, or available on an urban road - the allowable range
Bus Facility.) The issue of widening versus lane of dimensions is provided in the relevant parts of
conversion is also not addressed here; it will need this chapter. Typical dimensions of components
to be considered at the individual corridor level. are shown in the typical cross sections in Figures
Similarly, care must be taken to distinguish 7.2.12.5 to 7.2.12.10.
between the priority treatment type and the road
type - a kerbside bus lane has the same Chapter 5 provides details of the turning

7
characteristics no matter what type of road it is on requirements for buses and trucks, and discusses
or how the general-purpose lanes are treated. the needs of bicycles.
(Reference: PPK, 2000).
Access
Group A: Segment Treatments Ingress to and egress from buffer and barrier
separated Transit lanes should occur at
A-1: Kerb Lane
strategically located openings located sufficiently
A-2: Second Lane upstream and downstream of interchange ramps
to allow adequate weaving. Typical weaving zone
A-3: Median Lane length is 400m located 150m per lane-change
from the ramp (see Figure 7.2.12.11).
A-4: Contraflow Kerb Lane
For further details on access requirements, refer to
A-5: Contraflow Median Lane
Wilden (1997).
A-6: Single Reversible Median Lane
Enforcement
A-7: Two Way Median Lanes
Enforcement of the correct use of transit lanes is
All of these alternatives are illustrated in Figure required and adequate space to allow safe
7.2.12.1. enforcement activity has to be provided.

Group B: Intersection Treatments This can be achieved by using a continuous 3.5m

wide shoulder. This width is required to provide
B-1: Signal Priority Figure 7.2.12.2 space for the enforcement activity - a lesser width
will not be usable. Figures 7.2.12.5 to 7.2.12.8
B-2: Queue Jump Lane Figure 7.2.12.2 show typical arrangements for enforcement areas.
B-3: Advance Signal Figure 7.2.12.2 It may be possible to reduce the cost of a
continuous 3.5m shoulder by providing
B-4: HOV Turn Lane Figure 7.2.12.3
intermittent enforcement bays 100m long with
B-5: HOV Grade Separation Figure 7.2.12.3 appropriate deceleration and acceleration lanes
and tapers at each end. The length of the
Group C: Spot Treatments deceleration lane should be based on being able to
stop at the start of the bay; the length of the
C-1: Ramp Meter Bypass Lane Figure 7.2.12.4 acceleration lane should be based on a start speed
of zero at the end of the bay.
C-2: Priority Link Figure 7.2.12.4

C-3: Exclusive Ramp Figure 7.2.12.4

The dimensions of the lanes, medians and

separators required for these alternatives should
comply in principle with the requirements of this

September 2004 7-13

 Chapter 7: Cross Section Road Planning and Design Manual

TL TL TL

7
OR

ONE WAY TWO WAY

A1: Typical Arrangement, A2: Typical Arrangement,
Kerb Lane HOV Facility Second Lane HOV Facility

BUS STOP
TL TL TL

A3: Typical Arrangement, A4: Typical Arrangement, A5: Typical Arrangement,

Median Lane HOV Facility Contraflow Kerb Lane HOV Facility Contraflow Median Lane HOV Facility

AM
BUS STOP

TL
TL TL

PM

A6: Typical Arrangement, A7: Typical Arrangement,

Single Reversible Median Lane HOV Facility Two Way Median Lanes HOV Facility

Figure 7.2.12.1

7-14 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Traffic
Signal
Controller

Vehicular
Detection
System

7
BUS
B1: Typical Arrangement,
Signal Priority

TL OR TL

TEE Intersection
B2: Typical Arrangement,
Queue Jump Lane

TL TL
Right Turn from Kerb Lane Bottleneck

B3: Typical Arrangement,

Advance Signal

Figure 7.2.12.2

September 2004 7-15

 Chapter 7: Cross Section Road Planning and Design Manual

7 TL

B4: Typical Arrangement,

HOV Turn Lane

TL

TL TL
TL

TL OR

TL
TL

TL
B5: Typical Arrangement,
HOV Grade Separation

Figure 7.2.12.3

7-16 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

TL
7

C1: Typical Arrangement,

Ramp Meter Bypass Lane

TL

TL

C2: Typical Arrangement,

Priority Link

TL

TL

C2: Typical Arrangement,

Exclusive Ramp

Figure 7.2.12.4

September 2004 7-17

 Chapter 7: Cross Section Road Planning and Design Manual

general purpose 1.2m 3.5m 3.5m 3.5m 1.2m general purpose

lane reversible lane(s) lane

HOV LANE HOV LANE

SHOULDER CL SHOULDER

Figure 7.2.12.5 Barrier Separated Reversible Cross Section

7 1.2m 1.2m
general purpose 1.2m 3.5m 3.5m 3.5m 3.5m 1.2m general purpose
lane lane

HOV LANE HOV LANE

SHOULDER

Figure 7.2.12.6 Barrier Separated Two-Way Cross Section

3.0m general purpose 3.5m 3.5m 3.5m 3.5m general purpose 3.0m
lane lane

HOV LANE HOV LANE

SHOULDER SHOULDER

Figure 7.2.12.7 Concurrent Flow - Non-Separated HOV Lanes Cross Section

1.2m 1.2m
3.0m general purpose 3.5m 3.5m 3.5m 3.5m general purpose 3.0m
lane lane

HOV LANE HOV LANE

SHOULDER BUFFER BUFFER SHOULDER

Figure 7.2.12.8 Concurrent Flow - Buffer Separated HOV Lanes Cross Section

PEAK DIRECTION OPPOSING

TRAFFIC FLOW MOVABLE BARRIER TRAFFIC FLOW

general purpose
general purpose lane lane
HOV LANE

SHOULDER BUFFER BUFFER SHOULDER

Figure 7.2.12.9 Typical Contraflow Lane Configuration Cross Section

7-18 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

General Purpose Lanes

7
RAMP METERING AND HOV BYPASS LANE

General Purpose Lanes

Enforcement Area
Ramp Meter Signal
High-occupancy Vehicle Bypass Lane

Local Street
SEPARATED QUEUE BYPASS

Figure 7.2.12.10 Queue Bypass (See also Chapter 16, Figure 16.8)

Barrier

150m

150m 150m Start of Buffer

150m 150m

150m 150m

Exit Entry

Egress Distance at Ingress Distance at

a minimum of 150m a minimum of 150m
per lane change per lane change

Figure 7.2.12.11 Ingress and Egress Weave Distance at Buffer Separated Facilities

September 2004 7-19

 Chapter 7: Cross Section Road Planning and Design Manual

7.3 Shoulders • Sight distance across the inside of a horizontal

curve; and
7.3.1 General • Costs of the additional width, particularly
where the existing formation is being used - a
The shoulder is that portion of the carriageway
Cost Benefit analysis should be made.
beyond the traffic lanes, adjacent to, and flush
with the surface of the pavement. Its purpose is to
accommodate stopped vehicles, provide lateral 7.3.2 Two Lane Two Way Rural
support to the road pavement layers and, if sealed, Roads

7
offer improved conditions for cyclists.

The shoulder width is measured from the edge of Widths

the traffic lane to the verge. All safety barriers,
signs, guide posts, drains and kerbs are to be Table 7.7 lists shoulder width requirements for
contained outside the shoulder within the verge. two lane rural roads with minimal pedestrian
Fixed objects within the verge should be frangible and/or bicycle traffic.
or protected with a safety barrier (see Section 7.5,
A taper of 1:50 should be applied between
Verges).
different width shoulders that adjoin one another.
Factors to consider in deciding on shoulder width This taper transition may need to be lengthened to
include: ensure the taper’s appearance is satisfactory.

• Support for the pavement structure - 0.5m will

accomplish this; Table 7.7 Guidelines for Shoulder Widths

Nominal Situation
• Space for a driver to use to avoid a collision Shoulder
and regain control - the shoulder width will Width (m)
rarely be sufficient to accomplish this and the 0.5-1.0* Normally widths less than 1.0 m will be used
“clear zone” will be the area in which this only where overlaying is being carried out
with full formation sealing, and widening of
occurs. However, the wider the shoulder, the
formation is not justified.
more use it will be for this purpose - a width of
1.0* Minimum shoulder width for general use
3.0m would be desirable (North American (i.e. unless special reasons dictate
studies show that the accident risk is halved otherwise). Appropriate also when shoulder
when hard shoulder width is increased from 0.6 seal is desired and material cost/properties
dictate full normal paving material.
to 3.0m - Ref. 4);
1.5* Normal shoulder width with sealed or partly
sealed shoulders. Depends on availability of
• Clearance to posts and other fixed objects to
suitable material.
provide an adequate distance to the shy line
2.0-2.5* Suitable shoulder width on higher volume
(see Table 7.1) - (this will also allow marginal roads when periodic provision to stop
increases in the numbers of vehicles carried at completely clear of traffic lanes is difficult to
a particular level of service but this effect provide.
disappears over widths in excess of 1.5m); 3.0* Special cases where local issues dictate
(e.g. high speed high volume rural routes
where incidence of stopped vehicles unable
• Space for a stationary vehicle to stand clear or
to exercise choice as to location of stop may
partly clear of the traffic lanes - 2.5m is be significant). Normally only occurs on
required for a passenger vehicle to be clear of arterial outlets to major urban areas,
the traffic lanes and greater widths provide for especially if recreational routes.

additional clearance or for larger vehicles to * Shoulders between 0.5 m and 1.5 m do not enable a
vehicle to stop clear of traffic lanes. 2.0 m shoulders
stand clear; enable it to stop largely clear. A vehicle travelling 100
km would expect to encounter some 4 to 5 stopped
• Provision of a bicycle lane (see Chapter 5 and vehicles for every 1000 vehicles/hour using the road.
Figure 7.5); Of these something less than 5% would have little

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Road Planning and Design Manual Chapter 7: Cross Section

choice as to the exact location of the stop. There is 7.3.3 Multilane Rural Roads and
evidence that safety does not improve significantly for
shoulder widths over 1.5-2.0 m. Continuous 2.5 m
Motorways
shoulder can therefore be justified only on the highest
volume roads and where speeds are also high. What
is important, however, is to provide frequent
Rural Roads
opportunities to stop completely clear of the road (by
flattening slopes on at least some low fills, or making On a rural road with a median and two lanes or
provision at the transition of cut and fill) on all roads more in each direction the shoulders should be
with shoulders less than 1.5 m, and also on higher 2.0-2.5 m wide on the nearside and 1.0 m wide on
volume roads with shoulders less than 2.5 m.
the offside (median). Sealing is normally decided

7
on the same grounds as for rural two lane roads.

Shoulder Sealing
The need to provide lay bys on multilane roads is
not as critical as on two lane two way roads.
Shoulders should be sealed to a width of 0.5m However, consideration should still be given to
(min.) from the edge of the sealed lane when the providing these facilities, particularly for heavy
predicted AADT is less than 2000, and 1.0m vehicles, at reasonable intervals (see Chapter 20).
(min.) when the predicted AADT is greater than
2000. When provision is made for cyclists, a Motorways
wider sealed shoulder is required (see Chapter 5).
Shoulders on motorways will generally be at the
A full width seal should be provided: upper end of the range because of the high traffic
volumes combined with high speed operation. The
• Adjacent to a lined table drain, kerb or dyke; desirable minimum width of the nearside shoulder
(left hand side) is 2.4m but 3.0m will be justified
• Where a safety barrier is provided adjacent to a in some cases (e.g. Pacific Motorway). The
1.0 m wide shoulder; minimum width of the median shoulder is 1.0m for
• On the outer shoulder of a superelevated curve; a two lane carriageway, and 2.0m for a three lane
carriageway. Desirably, for 3 or more lanes, a 2.4m
• On floodways; median shoulder should be used to allow vehicles
to stop clear of the running lane. Note that shy line
• Where environmental conditions require it; distances to obstructions must be observed.
• Where rigid pavement is proposed;

• Where required to minimise maintenance costs; 7.3.4 Auxiliary Lanes

• In high rainfall areas. Nearside shoulder widths adjacent to auxiliary
lanes should generally be 1.0 m, widened to 2.0 m
Edge lines should be marked so that their inside
adjacent to a safety barrier and 3.0 m at merge
edge corresponds to the outside of the lane.
areas. At merge locations it is important that the
shoulder remain traffickable, thus a full width seal
is desirable. (Refer Figure 15.6, chapter 15.)

7.3.5 Ramps
Note: Sealing is sometimes continued beyond the
shoulder point and down the batter slope on the high Desirably, minimum shoulder widths on ramps
side to protect the pavement from ingress of water. On should be 2.0 m on the nearside and 1.0 m on the
floodways, the seal is continued down the batter on offside. Shoulder seal shall be full width. Under
both sides where no other protection of the batters is special circumstances the shoulders may be
provided.
reduced but the total carriageway width should
not be less than 7.0 m. The range of circumstances

September 2004 7-21

 Chapter 7: Cross Section Road Planning and Design Manual

for ramps is complex - detailed requirements are 7.3.7 National Highways

given in Chapter 16.
Table 7.9 gives parameters for the width of
shoulders on National Highways.
7.3.6 Urban Roads

On roads where a “traffic lanes + shoulders” Table 7.9 Shoulder Widths for National Highways
design is appropriate the considerations given for
rural roads apply similarly. However, urban traffic AADT One Way Two Way
Left Right Left Right

7
distributions tend to be different from rural
< 3000 2.0 1.0 1.5 1.5
conditions, in that urban arterial roads exhibit
frequently repeated peak hour flows. Operating > 3000 2.0 1.0 2.0 2.0

speeds well below free running speeds are

normally associated with design volumes.
Capacity is more important than speed. It is rare
that a full width, fully paved lane can be 7.3.8 Cycleways
economically justified as a full length breakdown
lane. Table 7.8 sets out guidelines for shoulder Where there is an identified requirement to make
widths for urban roads. provision for bicycle traffic, then an additional
width of seal may be added to the sealed shoulder
width, which may warrant shoulder widening. See
Table 7.8 Guidelines for Urban Shoulder Widths Figure 7.5.
Nominal Situation Sealed shoulders have a proven road safety
Shoulder
Width (m) benefit for all road users and reduce long term
0.0 No clearance normally required between road maintenance costs. Also, most main roads
traffic lanes and semi-mountable kerb will have some level of cycling as they provide
(e.g. raised medians). An offset of 0.5 m the only connecting routes between regional
to kerbs is desirable, and is required on
National Highways.
centres. Therefore, sealed shoulders will generally
be required on all main roads with special bicycle
0.5-1.0 Normal median shoulder with depressed
median. facilities necessary on urban main roads.
1.0 Minimum outer shoulder width for general
use (i.e. unless special reasons indicate
otherwise).
1.5-2.5 Normal outer shoulder width on major 3.0
urban roads (isolated stopped vehicles on
Width of Sealed Shoulder (m)

1.8 m shoulders have been shown to

have negligible effect on capacity or
safety). 2.0
3.0 Special cases where high volumes and
high speeds can coincide, i.e. where the
frequency of stopped vehicles (highest
because of high volumes) is associated
1.0
with high speeds of the through traffic.
This is normally associated with the
arterial outlets to major cities, where
recreational peaks are much “flatter” than
urban commuter peaks, and high 0.0
volumes just below those that 40 50 60 70 80 90 100 110 120
considerably reduce speeds, can persist 85th Percentile Speed of Trucks (km/h)
for long periods.

Figure 7.5 Recommended Sealed Shoulder

Widths for Cyclists

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Road Planning and Design Manual Chapter 7: Cross Section

7.3.9 Change in Shoulder Width When a median is provided on a rural road, it is

sometimes desirable to have it in conjunction with
Where the width of shoulder is changed for any independently aligned and graded carriageways.
reason, the transition from one width to the next is Special attention needs to be given to the
to be accomplished with a taper of 1 in 50. carriageway relationship to alleviate the effects of
headlight glare. Research has shown that the
minimum width median to adequately separate
7.4 Medians traffic without median barriers on high speed
roads is 15 m. In cases where a variable width

7
median is provided, the width should not be less
7.4.1 General
than the minimum widths discussed in 7.4.6.
A median is the strip of road, that is not normally On dual carriageways where the provision of
intended for use by traffic, which separates cross-median access for turning semi-trailers is
opposing travelled ways. The median width necessary, a wider median will be required to
includes the adjacent shoulders (see Figures 7.30, ensure that turning vehicles are sheltered from the
7.31 and 7.32). through traffic. In such cases the minimum
The strip of road within the median, excluding median width will be governed by the length of
adjacent shoulders, is called a “residual median”. the design vehicle expected to utilise the facility.
This may be reduced if the through carriageways
Medians: are widened to accommodate turning vehicles
(see Chapter 15, Intersections at Grade). If it is
• significantly reduce the risk of collision with uneconomic to maintain the wide median over the
opposing traffic; entire length of the road, then local widening may
be applied.
• improve capacity by restricting access to
property and minor side streets; Factors that need to be considered in reaching a
decision on this include:
• provide a safety refuge for pedestrians;
• What is the cost of the land required?
• prevent indiscriminate u-turn movements;
• Are there any other reasons why the land
• direct right turn movements to signalised
should not be taken (buildings, other
intersections and/or right turn bays,
developments, cane land, etc)?
• provide a place to collect run-off from the road
• How many vehicles will be using the crossing?
and carry the water to the drainage system; and
Is the likelihood of a vehicle having to
• accommodate safety barriers and glare undertake a two-stage crossing high?
screening.
• A 19m median would be desirable if affordable
and may allow safety barrier to be omitted; the
7.4.2 Rural Roads extra width allows more flexibility in the future
- the 15m is a minimum and results in a quite
It is a requirement for medians to be installed narrow median in the future if widening is
when a rural road is widened to four lanes or more undertaken;
or is constructed initially as a divided road. It is
• It may be possible to provide the 19m at the
also necessary to provide for a painted median at
intersections and use curves on each side of the
least 1.0m wide in those cases where passing
intersection to transition back to the “normal”
lanes in each direction overlap. These sections
median width;
become four lane sections and it is necessary to
provide at least this degree of separation of the
opposing traffic streams.

September 2004 7-23

 Chapter 7: Cross Section Road Planning and Design Manual

• If the intersection will be signalised in the near additional life to be achieved for the pavement
future, the width should be kept relatively small as a whole;
to avoid excessive clearance times;
• The adjoining sections at the start and end of a
• A seagull intersection to accommodate the two relatively short project have to be matched.
stage right turn and maintain a lesser median
width may be considered (see Chapter 13); Care is required to provide for the traffic
movements across the construction works at the
• If the right-of-way is available, and it is a rural access points.
area, it is likely that the costs of providing a

7 wider median can be kept to the same, or close The decision on future widening requires careful
to the same, cost as the narrower median. With consideration of the factors impacting on the road
a wide enough median, the possibility of in question and adopting the solution that
independent grading comes into play and the provides the best answer for the particular
costs may be reduced with smart design. circumstances.

When future widening is anticipated, it is

desirable to allow for it in the median width. The 7.4.3 Urban Roads
ultimate median width should not then be less
than the desirable width of 15 m. In urban roads it is desirable to provide medians on
roads of four lanes or more. Where six lanes are
Widening into the median will: required, medians are even more important. In these
cases, a carriageway width of >9m between kerbs is
• Minimise traffic disruptions during required to allow for at least two travel lanes plus a
construction of the widening; shared parking lane/travel lane. For carriageways
less than 9m, parking or breakdowns will restrict
• Minimise interference with roadside furniture,
flow and reduce road capacity. Medians can be
drainage installations and environmental
provided on roads with carriageways between 7m
protection devices;
and 9m between kerbs if:
• Prevent further environmental damage during
• mountable kerb and verge reinforcement are
construction of the widening; and
provided to enable vehicles to stop clear of the
• Avoid disturbing cut batters (particularly travel lanes (see Figure 7.28); or
important in potentially unstable or erodable
• other kerb types are used and the design hourly
country).
traffic volumes can be accommodated in one
There will be circumstances where widening on travel lane and separate right turn lanes are
the outside of the existing pavements will be the provided for significant turning volumes.
appropriate solution. These include:
Where signalised intersections are proposed,
• Existing ramps have to be remodelled to suit medians need to be wide enough to accommodate
current standards; signal posts, lanterns and servicing facilities. A
desirable median width of 2.4 m (for maintenance
• The existing median is inadequate to ladder spread) should be provided. At
accommodate the additional lanes and retain intersections other than six lane divided
sufficient width; carriageways with right turn storage lanes, (i.e.
locations with three lanes or less at the stop line),
• There is little disruption to the existing
the minimum median width of 1.2 m may be
drainage and other infrastructure;
applied, provided that all intersection movements
• The existing outer lane has less life remaining can be adequately controlled by overhead lanterns
than the inner lane and a new outer lane will on mast arms.
provide for the heavier loads allowing

7-24 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Table 7.10 gives a guide to recommended widths • It is preferable to use 5 or 7 mm aggregate as

for medians on urban roads. Typical treatments are the bedding medium for bricks and pavers, or
illustrated in the Typical/Cross Sections in Figure concrete slabs.
7.6.
• Where landscaping is used in medians it is
preferable to use hardy species that do not
Table 7.10 Urban Road Median Widths require extensive watering once established.
(Refer to Metropolitan District for guidelines
Total Residual Right
Median Median Turn on their experience.)

7
Width Lane
• If watering is required, care is required in
Desirable 5.9 2.4(1) 3.5
selecting a suitable system. “Keeping it simple”
Minimum 4.3 1.2(2) (4) 3.1
appears to be the most effective way (e.g.
Minimum 1.6 1.6(4) -
(Future traffic barrier,
providing watering points in the form of taps in
no right turn bays or (4.0) (4.0)(3) pits in the areas requiring watering). Automatic
significant pedestrians) systems can cause difficulties and must be
Absolute 0.9 0.9 - monitored closely.
Minimum
(No right turn bays, no
traffic barrier, no traffic
• Consideration should be given to safe
signals) pedestrian use of raised medians where
Notes: drainage channels are specified to facilitate
(1) Where traffic signals are proposed, the median cross median flows of pavement runoff. In
width is to continue for a minimum of 3 m each side urban areas, it is not unreasonable for
of the central traffic signal post. pedestrians to cross the road using the median
(2) 1.2 m allows for single lantern traffic signal display, as a refuge. Drainage slots pose a hazard to
minimum pedestrian storage and clearance to
signs. 1.5 m allows for dual 200 mm lantern display. pedestrians due to a sudden step down from the
(3) Where two stage mid-block signalled pedestrian
median surface. Wherever possible, the use of
crossings are required, the desirable width for medians with drainage slots as a pedestrian
pedestrian storage is 4 m. refuge should be avoided. However, if this is
(4) Where pedestrians are likely to accumulate on not possible then the following solutions may
medians the width should be a minimum of 1.5 to be considered to improve safety for
2.0 m.
pedestrians:
- delineation of the edges of the drainage slot
- making the drainage slot wider (it then
Tips for Treatment of Urban Medians
becomes a clear step down and step up)
• Narrow medians and noses of medians at - edging the slot with mountable kerb or
intersections should generally be treated with a similar sloped edge
"hard" surface. A most effective treatment is
- replacing the slot with a small box channel
stamped concrete (or similar) in an appropriate
colour (often terracotta). - covering or plating the slot
- fencing the median to discourage pedestrian
• Exposed aggregate treatment should be avoided use.
because the slurry from the process is washed
into pipes and waterways thereby causing Replacing the slot with a box culvert or
blockages and/or environmental harm covering/plating the slot is not recommended as
this may result in a maintenance issue.
• Where bedding sand is used under bricks or
pavers or concrete slabs, the sand must be
treated with a suitable poison to avoid
infestation with ants, which create voids under
the paving.

September 2004 7-25

 Chapter
Road7:Planning
Cross Section
and Design Manual Road Planning
Chapter
and Design
7: Cross
Manual
Section

7.4.4 Motorways 7.4.6 Rural Median Treatment

Where possible, the median provided for In rural areas, depressed medians are preferred
motorways should be as for rural roads above. In and a width of 15 m is the desirable minimum.
constrained urban situations, narrower medians Where a distance of 15 m cannot be achieved,
provided with barriers may be appropriate. The acceptable widths are those that provide an
width available for the median will dictate the acceptable clear zone width for traffic in each
type of barrier to be used based on the deflection direction between the edge of travelled lane and
of the barrier type chosen but the various types of the edge of verge of the opposite carriageway. If

7
barrier do have minimum width requirements. this width cannot be achieved, median barrier may
Details are provided in Chapter 8. be required (see Chapter 8).

If future widening is likely, the widening should In depressed medians, slopes of 1 on 10 are
be applied on the median side of the carriageways. preferred with a maximum preferred slope of 1 on
Therefore, the width of the median in the first 6. A slope of 1 on 4 should only be adopted in
stage should be such that the width after widening constrained areas. Landscaping or fencing may be
meets the minimum width required. Desirably, required to prevent U-turns if safety barrier is not
this should be at least 15m to provide the safest used.
situation. In constrained cases, however, the
minimum will be that required to accommodate a Longitudinal drainage of medians should drain
concrete barrier with a clearance of 2.0m (3.0m from both sides to appropriate gully pits (i.e. no
for 3 or more lanes) to the face of the barrier. This blocks). Where blocks, levees, median cross overs
provides for the “shy line” distance on the median and the like are required, the slopes facing traffic
side (see Table 7.1). should be 1 on 20 (1 on 6 absolute maximum).
Where longitudinal culverts are required in the
Extensive use of concrete barriers is not a median (e.g. under a cross over), the ends shall be
preferred option on environmental grounds and sloping (1 on 6 maximum) and provided with
this should be considered when determining parallel bars at right angles to the traffic.
median widths.
Longitudinal culverts in the median should be
avoided if at all possible. A much better
7.4.5 Clearance to Medians arrangement is to collect the water in a drop inlet
and dispose of it to the roadside or into adjacent
In a lit area with a design speed of 80 km/h or less, cross drainage installations.
no lateral clearance is required from the edge of
travel lane to a raised median (i.e. one with a In general, medians should be kept clear of
mountable kerb). However in an unlit speed zone obstructions within the clear zone requirements of
of 80 km/h or less, a 0.5 m lateral clearance is the road. Designs should avoid the use of head
required to a raised median. The gutter adjacent to wall, unprotected culvert openings, solid sign
the kerb face, if provided, is located outside the foundations, non-frangible sign posts and light
lane. poles in the median. Planting should consist of
“frangible” species of ultimate trunk diameter not
In areas where the design speed is greater than 80 greater than 80 mm unless it is outside the
km/h and no street lighting exists, a lateral offset required clear zone and/or is located behind the
of 1.0 m is required, measured from the edge of appropriate barrier. Landscaping design and
the lane to the bottom face of the kerb (Types 8 - species selection will depend on the specific
15). If lighting is provided, the clearance may be circumstances and requires specialist input.
reduced to 0.5 m.
The design of the median should ensure that it is
as maintenance free as possible. This will
minimise the amount of time that maintenance

7-26 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

personnel will be required to spend on the median Generally verges are not provided in urban areas.
thereby reducing their exposure to traffic hazards. However, if a situation arises where they are
required, then the verge widths specified in Table
Features limiting the horizontal sight distance on 7.12 should be adopted.
curves must be located such that adequate sight
distance is achieved. Offsets needed to achieve
this are given in Figure 7.6. 7.5.2 Footpaths
Figure 7.6 shows a range of acceptable treatments Generally, footpaths provide room for:
for medians in rural areas. More details are shown

7
in the Typical Cross Sections given in Section 7.12. • Pedestrian movement;

• Bicycle travel;
• Public Utility Plant (PUP) installations;
7.5 Verges, Footpaths and
Outer Separators • Turning movements between the carriageways
and adjacent property entrances;
7.5.1 Verges • Road signs and lighting standards;
• Landscaping; and
The area between shoulder and batter hinge point
is the verge and is used for installation of • Bus bays.
drainage, guardfences, and batter slope rounding.
Width
The recommended minimum verge width on an
embankment with guideposts is 0.5 m and with a The minimum footpath width to be adopted is 2.0
non-rigid safety barrier, 1.0 m. At difficult sites m. This will provide 1.5 m for pedestrians plus an
the verge may be narrowed to 0.75 m for safety allowance for lighting standards and road signs.
barrier placement, however special foundation However, much greater widths are required as
treatment will be required to ensure that the standard dimensions, particularly in commercial
material behind the safety barrier provides and industrial areas and on Arterial Roads.
adequate support for the system.
This is because the width required for the Public
Table 7.12 shows the recommended verge widths Utility Plant allocations is usually much greater
and Figure 7.7 shows typical cross sections of than that required for the pedestrian movement. A
various verge treatments. minimum width of 3.6 m is required for these
reasons and greater widths are sometimes
necessary. Detailed footpath requirements should
Table 7.12 Recommended Verge Widths be determined in conjunction with the relevant
Formation Verge Function
Local Government and Public Utility Plant
Configuration Width (m) Authorities.
Embankment 0.5 Min. rounding, with
space for guide posts Table 7.13 sets out desirable widths for footpaths
0.75 Minimum verge for on Arterial Roads. Any residual road reserve
non-rigid safety should be allocated to the footpath to provide
barrier (special cases additional space for landscaping and driveways.
only)
1.0 Desirable rounding,
min. verge for safety
barrier
1.0 to 3.0 Safety barrier flare
and anchorage
Cutting 2.0 min Table drain
1.5 min Concrete lined drain

September 2004 7-27

 Chapter 7: Cross Section Road Planning and Design Manual

1.0 1.0

rounding rounding
1 on 4 1 on 4
or flatter Rounding or gutter or flatter

9.0 minimum

Dependently aligned with depressed median

7 1.0

0.5

rounding

1 on 4
or flatter

Independently aligned with single slope median

1.0 1.0

* *

Minimum median
* Allowance for dynamic deflection of barrier
needs to be considered. See Chapter 8.

1.0 1.0

#
Mature bushes
# Refer Chapter 11, Section 11.
(Table 7.11 provides an example for 110km/h)
Landscape treatment on right hand curves (see Table 7.11)
Table 7.11
Offsets for Sight Distance at 110km/h

Curve Radius Offset 1

(m) 110km/h (m)

800 5.5
1000 4.0
1500 2.02
2
2000 2.0
Notes:
1. Based on median lane width of 3.5m.
2. Minimum for shy line.

Figure 7.6 Median Treatment

7-28 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Batter Verge 1.0m (min) Shoulder 1.0m (min)

0.5m
Crossfall
7
Hinge Point

Rounding
Embankment (showing safety barrier location)

Batter Verge 2.0m (min) Shoulder 1.0m (min)

*
Table drain Crossfall

1 on 4 Table drain invert should be below the

0.1m design sub-grade level to ensure
drainage of the pavement layers.

Hinge Point * See Section 7.9.1 Cutting (unlined table drain)

Batter Verge 1.5m (min) Shoulder 1.0m (min)

Berm Type 22/28

(var.)
Type 22/28 channel may be
used within the road
1 on 10 Crossfall shoulder. Where cyclists
are provided for, shoulder
Hinge Point width must be in accordance
with Section 7.3.8.
Concrete 0.1m thick
Cutting (concrete lined table drain)

Figure 7.7 Typical Sections Detailing Verge

 Chapter 7: Cross Section Road Planning and Design Manual

If kerbed footpaths are not provided then Vehicle templates for standard large and small
sufficient verge width should be available to passenger cars should be used to ensure that these
enable pedestrians to walk clear of the road vehicles can use the driveway without bottoming
carriageway (i.e. lanes and shoulders) preferably on any part of it (see Appendix A).
outside the clear zone.
Public Utility Plant (P.U.P.) Allocations
For shared pedestrian/bike paths, refer to Chapter
5, Section 5.5.4. Public Utility Plant is usually located under urban
footpaths in accordance with standards negotiated

7
between the various Local Governments and the
Table 7.13 Desirable Widths for Footpaths on Service Authorities. While some degree of
Arterial Roads
standardisation has been achieved, there are
Road Type Footpath Width (m) differences between Local Governments and the
Residential Commercial actual distribution in any area will have to be
and Industrial determined for that area.
Urban Arterial Roads 5.5 5.5
Other Urban Roads 4.0 5.5 Some typical space allocations are shown in
Based on: Figure 7.11(a). These are taken from the Standard
• 4.0m - Services Requirement. Where a footpath is Drawings prepared for the then Institute of
wider than 4.0m, the services allocation should Municipal Engineering Australia, Queensland
remain at 4.0m. Division in 1995. All cases must be treated on
• 5.5m - Bus Bay and Landscaping Requirement. In their merits and the advice of the relevant Local
order to maintain capacity on major urban roads,
Government obtained to ensure that the standard
bus bays should be provided where possible within
the footpath width. A 5m minimum footpath width is practice for the area is implemented.
necessary at the bus bay site. Between bus bay
sites, the width surplus to services requirements Figure 7.11(b) also provides information on
may be allocated to landscape planting. typical depths of cover to services under roads and
footpaths. Table 7.14 sets out nominal depths of
cover for the various utilities. This information is
Footpaths and Driveways provided as a guideline only and specific details
must be obtained from the relevant Authority for
Many councils have minimum design all projects. Notwithstanding the cover given in
requirements which should be considered for the Figures 7.9, 7.11(b) and Table 7.14 under roads,
provision of footpaths. for crossings under declared roads, the minimum
cover (unless otherwise approved) is to be:
Typical driveway crossings for high and low level
footpaths (to be used as a guide in the absence of • 600 mm below the invert of table drains;
local council regulations) are given in Figure 7.8.
• 1200 mm minimum below the existing or
Depressed footpaths introduce drainage problems future roadway;
and therefore should only be considered where
access conditions or the high costs involved in • 600 mm elsewhere;
property and utility adjustments restrict alteration
provided that there is also a minimum cover of
to the existing footpath levels.
300 mm below the level of the existing or
A desirable verge side slope of ±1 on 6 may be proposed sub-grade.
used at locations adjacent to parks, reserves etc.
where driveways are not required.

In difficult terrain this side slope may be increased

to ±1 on 5.

7-30 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

* See Figure 7.21 for details.

# Required for wheel chair access (Australian Standard AS 1428.1).
Figure 7.8 Typical Driveway FCrossings

New Road Surfacing

500 min*

New Road Pavement Marker tape

75 min
Lean mix concrete*

Bedding sand*

25 min 75 min
50 min 50 min
450 min*

* See Standard drawing 1149

TYPE 1A
NEW ROADWAY (AFTER PAVEMENT CONSTRUCTION)
LV (240V)
Refer also to Standard Drawing 1149 Ducts for Underground Electrical Conduit
• New and Existing Roadways; • Bored Crossings; • Single and Multiple Conduits
Figure 7.9 Installation of Underground Conduits within the boundaries of Declared Roads

September 2004 7-31

 Table 7.14 Nominal Depth of Cover for Various Utilities

Cover Electricity Gas Communications Water

Footway Roadway Footway Roadway Footway Roadway Footway Roadway
300 Communication
cables in
shared trench
450 Communication Urban Urban Local Local
cables in 500kPa network network
shared trench cables & cables &

7
conduits conduits
phone/ phone/
pay TV pay TV
500 Rural 100m pipe
Intermediate
sizes for
DICL
600 LV cables LV cables 500kPa Other Other 740mm pipe 100mm pipe
network network Intermediate Intermediate
cables & cables & sizes for sizes for
conduits conduits UPVC & GRP DICL
700 750mm pipe
750 HV cables to HV cables to 1000kPa Rural 100mm pipe
22kV 22kV 500kPa Intermediate
sizes for
UPVC & GRP
900 HV cables to HV cables to 1000kPa 750mm pipe
33kV & above 33kV & above
1000 750mm pipe
1200 3500kPa 3500kPa
Note: DICL Ductile Iron Cement Lined UPVC Unplasticised Poly Vinyl Chloride
GRP Glass Reinforced Plastic
WARNING
This Table shows nominal laying depths of services by various Authorities and is for information only.
EXISTING SERVICES MAY BE LAID AT DEPTHS AND LOCATIONS OTHER THAN THOSE MENTIONED.
It is important that consultation be made with the respective utility Authorities for an indication of the presence of a service.
Hand excavation to determine the exact utility location is advised prior to using any mechanical equipment.

Designers must consider the potential to protect 7.5.3 Outer Separators

existing PUP rather than relocating it when a
project changes the road alignment. For example, General
a Telstra access chamber could be left under the
pavement and an access provided from the An outer separator is the portion of road reserve
footpath rather than relocating the whole separating a through carriageway from a service
structure. or frontage road, as shown on Figure 7.10.

Appropriate risk assessment should be undertaken

together with consultation with the appropriate
Authorities, to determine the most economical
solution. The resulting plan must be approved by
the relevant PUP Authority.

Overhead services require special consideration -

Figure 7.10 Outer Separators
see Section 7.10.7 for details.

7-32 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Figure 7.11 (a) Typical Service Corridors and Alignments

September 2004 7-33

 Chapter 7: Cross Section Road Planning and Design Manual

Figure 7.11 (b) Typical Service Conduit Sections

7-34 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Outer separators: road and also to allow parking in the service road.

• separate and act as a barrier between traffic In rural areas, an outer separator width of 15m is
flows on the through carriageway and a desirable, particularly where the service road is
service/frontage road; two way.
• provide visual separation of the two flows;

• provide headlight glare screening especially Table 7.15 Typical Widths of Outer Separators

where the service road carries two way traffic; Factor Situation Width (m)

7
(excluding
• provide walking or standing space for shoulders)
pedestrians; Physical Safety barrier with or 0.5
Separation without glare screen
• accommodate roadside planting; Safety barrier with kerbs 1.0
on both sides
• accommodate guard rails and other barriers,
Visual Two way operation on Light traffic on
fencing, lighting poles and signs; Separation service road with no service road:
artificial glare screen 5.0
• accommodate differences in levels between the Medium to heavy
through carriageway and the service road; traffic:>7.0
Headlight Planting shrubs as 2.0 - 5.0
• provide space for bus bays; Glare the screen
Screening Artificial Screen 0.5 - 1.0
• accommodate service installations in special Pedestrians Occasional usage or if 2.0
cases (primarily “trunk” services when the Cyclists part of a designated
normal footpath allocations are already used); bicycle route
Shrubs for screening 4.0
• reduce the number of conflict points likely to (including walking space)
occur through the number and frequency of use Trees and Shrubs 4.0 - 5.0
of property access points between successive Space for Safety barrier, fencing, 0.5 - 1.0
Roadside lighting standards etc.
intersections; and Furniture
• eliminate the need to provide parallel parking Bus Bays Indented into outer 6.0
separator (min. 5.0)
on the through carriageway, thereby increasing
Intersections Traffic Signal Control 2.4 min.
the capacity of the through carriageway.
Note: Where safety barrier is used, allowance for
deflection must be made.
Widths

Table 7.15 provides typical widths that will meet a

range of circumstances. These tend to be the Slope
minimum required to meet those circumstances and
it is desirable to use greater dimensions if possible Where outer separator side slopes exceed 1 on 4
in the space available. When allocating space to the or 1.0m in height, safety barrier protection
various components of the cross section, a adjacent to the higher of the two roads, may be
reasonable balance between the competing needs warranted.
has to be maintained. For example, where traffic
At intersections where traffic signal control is
signal control is to be used at intersections, extra
proposed, the outer separator should have a
width available is better allocated to the outer
maximum side slope of 1 on 8 maintained for at
separator than the median once the minimum needs
least 3 m before and after the signal post.
of the median have been met.

However, it is desirable that an outer separator be

of sufficient width to absorb level differences
between the through carriageway and the service

September 2004 7-35

 Chapter 7: Cross Section Road Planning and Design Manual

7.6 Clear Zone damage to an errant vehicle and its occupants.

• the desirable width of a clear zone is dependent

7.6.1 General on predicted traffic volumes, traffic speed and
road geometry.
The intent of the clear zone is to provide space for
the driver of a vehicle that runs off the road to Figure 7.12 is a nomograph that allows for the
regain control while sustaining minimum damage appropriate clear zone distance to be determined.
to the vehicle and its occupants. It is the width of These distances represent a reasonable measure of
roadside, beginning at the edge of the travelled the degree of safety appropriate for a particular

7
way, that is available to the driver to take this road and must be balanced by comparing land use
action. and costs. The widths given are approximate only
and the nomograph should not be used to infer a
This zone will depend on the location of the
degree of accuracy that does not exist.
vehicle at any point along the road and is
determined for both sides of the vehicle (right Where it is not possible to provide an adequate
hand side for medians). Accordingly, the clear clear zone, free of non-frangible obstacles for the
zone distance is related to predicted traffic appropriate distance, a safety barrier should be
volumes and speed (see Figure 7.12), and takes considered in accordance with Chapter 8 of this
into account the widths of adjacent lanes, manual.
shoulders, medians, verges, footways and
traversable batters. See also Figure 7.1 and Table The provision of a clear zone is often better
7.21. practice than the erection of a safety barrier (due
to the length of the safety barrier generally
required).
7.6.2 Guidelines

To be regarded as part of the clear zone:

7.7 Crossfall
• the area should be:
- relatively flat, with a maximum side slope 7.7.1 General
of 1 on 3 (cutting) and desirably 1 on 4
(embankment) or flatter; and Crossfall is defined as the side slope, normal to
- traversable, having slope changes that will the alignment, of the surface of any part of the
keep all wheels of an errant vehicle in carriageway. Crossfall is provided primarily to
contact with the ground (this assists the facilitate pavement drainage.
driver of an errant vehicle to regain control).
The usual arrangement for straight sections of
See Figure 7.16 for determining appropriate
road is for the pavement crossfall to slope down
rounding for traversable batter slopes within
from either the centreline or the median.
clear zones.
However, the designer should not be limited to
• the area should be kept clear of all large, fixed this arrangement as inwards sloping crossfall, or
objects (such as species greater than 80mm in one way crossfall may be useful for certain
ultimate trunk diameter, structure support piers, grades, drainage or side slope situations.
culvert headwalls, large solid [i.e. non-
For wide multilane pavements, it may be
frangible] sign support structures, non-
appropriate to crown the pavement with one or
traversable gutters and barriers) which are of
two lanes draining to the median. This minimises
such a size that they cause unacceptable rapid
the depth of flow on the pavement surface,
deceleration rates to the occupants of an
reducing aquaplaning potential.
impacting vehicle. Only objects which will
collapse or break away on impact should be On curved alignments, the carriageway may slope
located in the clear zone to ensure minimal upwards from the centreline or median to help

7-36 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Figure 7.12 Clear Zone Nomograph

September 2004 7-37

 Chapter 7: Cross Section Road Planning and Design Manual

counteract the centrifugal forces on a vehicle above those given in Table 7.16, then the
travelling around the curve. This form of cross maximum sustained crossfall should not exceed
slope is known as superelevation. Chapter 11 4%; local increases to 6% are acceptable, but only
details the amount of superelevation required on in extreme cases. Stability of high vehicles
curves of varying radii, and the methods of becomes a problem on crossfalls greater than 6%.
superelevation development. Clearance of high vehicles to poles, signs, etc.
should also be checked (see Section 7.10.3).
Changes from one crossfall to another shall be
transitioned over a length to satisfy the rate of Crossfall should be provided on right turn lanes in

7
rotation and relative grade requirements given in a manner that ensures that the bay is adequately
Chapter 11. Sufficient dimensions, levels, cross- drained, and minimises the amount of water at the
sections and/or profiles should be provided on the median nose area.
construction drawings to enable the design to be
accurately reproduced in construction. Multicombination Vehicle (MCV) performance is
influenced by crossfall. The crossfall on freight
routes should not exceed 3%.
7.7.2 Crossfall and Drainage
However, on low trafficked roads where better
Crossfall has the important function of shedding surface drainage is required to protect low quality
water from the roadway to reduce the possibility paving material, a crossfall of 4% has been used
of a vehicle aquaplaning in wet conditions. successfully. This crossfall also tends to
Details of the relationship between crossfall and encourage MCVs to travel closer to the centre of
pavement drainage design are given in the Road the pavement with a consequent advantage of
Drainage Design Manual (Main Roads, 2001). reducing damage to the pavement edges.

Cross-over Crown Line

7.7.3 Road Crossfall
On straight sections of road, the maximum
algebraic change in crossfall over a crown line is
Typical crossfalls, depending on the type of road
7%.
surface are shown in Table 7.16.
Where a turning roadway exits from a
carriageway, and a different crossfall is required
Table 7.16 Typical Pavement Crossfalls on the through road and the turning roadway, the
algebraic change in crossfall over the crown line
Road Surface Traffic Lane Shoulder
(%) (%) formed must be limited to the values shown in
Cement Concrete 2.0-3.0 2.0-4.0
Table 7.16 (a).
Asphaltic Concrete 2.5-3.0 2.5-4.0
Sprayed Seal 3.0-4.0 3.0-4.0 Table 7.16 (a) Difference in Crossfall at Crossover
Unsealed 3.5-4.0 4.0-5.0 Crown Line - Turning Roadways
Within Floodways 1.0-2.0 1.0-2.0
Speed Max. algebraic difference in
km/h crossfall at crossover
crown line, %
< 30 Determined by vehicle clearance
There are many controls in urban areas which
30 - 50 6
force departures from the above values.
> 50 5
Differences in levels between kerb lines can Turning roadway with tapers:
sometimes be taken up by offsetting crown lines or speed = ‘average running speed’ of through road
adopting one-way crossfalls (see Section 7.7.6). Turning roadway without tapers:
speed = design speed of turning roadway
If it is necessary to increase traffic lane crossfalls

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Road Planning and Design Manual Chapter 7: Cross Section

Turning speeds for various combinations of radius Provision for visually impaired people should be
and crossfall are shown in Chapter 13, Figure in accordance with Australian Standard AS 1428.4.
13.38. It is preferable to limit adverse crossfall to
-3%, with an absolute maximum of -4%. Figure 7.13 illustrates these requirements.
Maximum positive crossfall on turning roadways
is 7% (see also Chapter 13, Section 13.8.2.1).
7.7.6 Parking Lane Crossfall
For a turn executed at very slow speed (say <10
km/h), the desirable maximum adverse crossfall In general, the crossfall on the parking lane should
be the same as the through lanes, but in some

7
should be -5% with an absolute maximum of -7%.
situations the crossfall may be varied. The
maximum crossfall of the parking lane should be
7.7.4 Median Crossfall 5%. The maximum algebraic difference between
the through lane and parking lane should not
Medians up to 8 m wide are generally level or exceed 8%. (Reference - Qld Department of Main
follow the crossfall of the road. Depressed Roads: Urban Road Design Volume 1, 1975 -
medians greater than 8 m wide should have a Chapter 3 and Main Roads Deparment Qld -
desirable crossfall of 1 on 10 (see also Section 7.5, Road Design Manual Volume 1 - Chapter 7.)
Figure 7.6).

At intersections where signals are to be installed, 7.7.7 Crossfall Configuration on

the median cross slope must match the slope of Side Slopes
the road through the intersection and should not
be greater than 6%. Where there are significant differences in levels
between opposite sides of a road, many problems
occur with conventional design including
7.7.5 Footpath Crossfall restoration of access and costly adjustments to
properties or public utilities. An option to consider
It is usual to slope the footpath towards the road is to adopt a one way crossfall.
so that water does not drain on to adjoining
properties. Where it is not possible to do this, In these circumstances the one-way crossfall
drainage onto adjacent properties will have to be should not exceed 4% (3% is preferred). For
arranged with the property owners. It is not aesthetic reasons the slope should extend full
usually an issue in rural areas. width between gutters (from lip to lip, including
the median). However, if drainage into the gutter
The design of the footpath requires consideration on the high side is considerable, the crossfall of
of several factors: the kerbside lane can be reversed to a maximum
• Drainage across the footpath; of 4% to increase the gutter capacity. The
resulting break in the crossfall is called an offset
• Pedestrian requirements for a walkway; crown and is usually located at the offside edge of
• Use by wheel chair bound people; and the kerbside lane. The development of the offset
crown requires careful design to avoid having the
• Requirements for visually impaired people. crown cross vehicle paths. Figure 7.14 shows both
desirable and undesirable methods of developing
Drainage is best served by a crossfall of 3% but
an offset crown.
this conflicts with the need to accommodate
wheel chairs. A maximum crossfall of 2.5% Whilst a one-way crossfall design is often
should be adopted to accommodate wheel chairs - satisfactory in sloping country, there are areas
2% is preferred (see AS1428.1). In these with steep slopes where this method will not meet
circumstances, care will be required to ensure that requirements. Under these conditions it may
water does not accumulate on the walkway or become necessary to consider other solutions,
become a hazard to people with disabilities.

September 2004 7-39

 Chapter 7: Cross Section Road Planning and Design Manual

Figure 7.13 Footpath Crossfalls

such as providing parallel service roads or split Attention needs to be given to the following
level carriageways. design aspects of split level carriageways in urban
areas:
Widening Two Lane Roads - Offset
Crown • provision for pedestrians;

Where an existing two lane road is to be widened, • access for local traffic;
it may be more economical to widen on one side,
retaining the existing crown of the road. This will • the design of intersections;
result in an offset crown to one side of the new • the provision of traffic signals, and
centre line. Provided that the offset crown is not
more than 1.5m from the new centre line, this • the provision of a central traffic barrier.
result is acceptable. The crown line in these
circumstances is barely perceptible to the driver. For rural situations, attention must be given to:
However, where the offset crown is closer to the
• access for local traffic;
edge line than the centre line, the effect is
disturbing to the driver and is unacceptable. • the design of intersections; and

• the provision of a central traffic barrier.

7.7.8 Split Level Carriageways

In extreme cases of side slope it may be necessary

to adopt a split level carriageway by providing a
steep batter or retaining wall in the median.

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Road Planning and Design Manual Chapter 7: Cross Section

Figure 7.14 Development of Offset Crown

7.8 Batters • the effects of long term exposure to the

elements (weathering) on the stability of the
7.8.1 Batter Slopes cutting;

• lining the catch drains to minimise failure of

Batters are the side slopes of cuttings and
the cutting by the leaching of fines through the
embankments. The slope is expressed as a ratio,
exposed cut face;
one unit of vertical rise on the horizontal distance
X (1 on X). • erosivity of the batter soils;
Maximum slopes are determined from the • the ease and cost of maintaining the adopted
geotechnical properties of the materials involved. batter slope;
Consideration should be given to the following
factors when selecting batter slopes: • traffic safety and possible economy by
eliminating safety barriers and using flatter
• the test results and any recommendations given slopes;
in the geotechnical report;
• appearance and environmental effects, and

September 2004 7-41

 Chapter 7: Cross Section Road Planning and Design Manual

• the overall economy of the project. a maximum of 1 on 3. Alternatively, a continuous

flatter slope not steeper than 1 on 4 could be used.
Slopes flatter than the maximum should be used
where possible. Generally flatter batter slopes are Cut Batters
safer, more resistant to erosion and have a better
appearance. The cost of stabilizing, planting and Earth cut batter slopes should not exceed 1 on 2
maintaining steep slopes may exceed the cost of unless the constraints are such that a steeper slope
the additional earthworks and road reserve is required and the Geotechnical investigation
required to provide a flatter, possibly traversable shows that steeper slopes are stable.

7
slope. Flatter slopes also reduce the extent of
In rock cuttings:
safety barrier and reduce potential environmental
impacts (erosion and sedimentation). However, • adopt an absolute maximum slope (subject to
the impact of flatter batters must be balanced geotechnical acceptability) of 1 on 0.25;
against the desirability of retaining significant
native flora, other environmental issues and • place benches at suitable locations in cuttings
property impacts. over 10 m high (see 7.8.4);

Maintenance vehicles can work on slopes up to 1 • provide access through any debris barrier to
on 3 but 1 on 4 slopes should be used where assist removal of debris;
practicable. • provide appropriate clearances between the top
On cut and fill slopes less than 1m high, batters of the batter and other obstructions and the
not steeper than 1 on 6 are preferred. boundary to assist maintenance including
collection of debris from cutting slopes;
For initial planning adopt slopes of 1 on 3 to 1 on
• provide catch banks at the top of the batter.
4 for heights of cut (excluding rock) and fill up to
2.0 m (3.0 m on Highways and Motorways).
Above these heights, 1 on 2 may be adopted but it 7.8.2 Traversable Batters and
is preferable to use 1 on 3 maximum wherever Batter Rounding
practicable at the planning stage. Actual slopes
adopted in design must consider all of the factors Rounding at tops of cuttings and embankments
discussed. can reduce scouring, remove loose material and
improve the appearance of the road. The amount
Fill Batters
of rounding on the top of cuttings usually depends
In addition to the general requirements set out on the material, the depth of rock (if any) and the
above, it is desirable for fill batters to be as flat as natural contours of the ground.
possible. Fill batter slopes flatter than 1 on 4 (1 on Traversable embankment batters assist by
6 preferred) should be used wherever practicable. providing an errant vehicle an opportunity to
The maximum fill batter slope should be no recover and return to the through carriageway, by
steeper than 1 on 2 (1 on 3 preferred) to assist maintaining all wheels in contact with the ground.
revegetation. Where practicable:
Traversable batters shall have the following
• adopt 1 on 4 slopes wherever mowing is attributes:
required, and
• embankment batter slopes of 1 on 4 or flatter;
• flatten batters as a preferred treatment to
providing guardrail. • cutting batter slopes of 1 on 3 or flatter;

Where excess spoil is available, consider flattening • roundings shown in Figure 7.16 or greater at
the fill batters to 1 on 6 over the width of the clear hinge points;
zone, increasing the slope beyond the clear zone to • channels with 1 on 4 slopes or flatter.

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Road Planning and Design Manual Chapter 7: Cross Section

1 on 3 embankment slopes can be traversed by Cut batters often require some form of treatment to
vehicles but it is unlikely that it can recover on minimise erosion and provide for stabilising the
that slope - 1 on 4 accommodates recovery. On cut slope surface. Revegetation should be encouraged
batters, the 1 on 3 slope directs the vehicle back to as far as possible. Where designed landscaping is
the road and therefore allows for recovery. A 1 on implemented, the treatments will be defined and
4 slope allows this manoeuvre to be undertaken may vary from reasonably flat slopes on which
with better control than on the 1 on 3 slope. formal planting is undertaken, to slopes as steep as
1 on 2 where hydraulic seeding and mulching may
Where batters have a potential impact severity of be carried out. In other cases, revegetation will

7
3 or more (refer to Chapter 8), the surface finish is occur more readily if the batter slopes are
to be free of elements that may snag components constructed to hold topsoil and minimise erosion.
of errant vehicles, causing them to yaw (spin) at Stepped (or serrated) batters (as illustrated in
unacceptable rates. The batter slopes are to be Figure 7.17) may often provide the necessary
formed similar to accepted safety barrier shapes, conditions for revegetation but these should not be
especially at the entrance to cuttings. used in dispersive soils (e.g. sodic soils). Further
environmental considerations and guidelines for
designing batters are provided in Chapter 3.
7.8.3 Batter Slope Treatment
The slope and treatment to be adopted is
Variable batter slopes can be used to improve a influenced by the type of material encountered
road’s appearance by blending it into the and the available right of way. Figure 7.18
surrounding terrain. This treatment can smooth illustrates several alternative treatments that may
the transition between cutting and embankment, be used subject to the stability of the slopes and
assisting the provision of lay-by areas. walls involved.
Common treatments adopted are constant batter
slope or constant batter catch point type. Constant 7.8.4 Benches
batter catch points are preferred because of the
improved appearance by blending various slope A bench is a near horizontal ledge that is
batters into surrounding terrain. Catch points at a constructed on a side slope to provide sight
constant distance (8m suggested) from the distance, slope stability and assist with batter
formation edge in light earthworks or at the ends drainage.
of adjoining cuts and fills in heavier earth-works
create a pleasing appearance at very small Benches are used on the face of batters to:
additional cost and should be adopted wherever
• reduce surface water run-off;
practicable (see Figure 7.15 and 7.15(a) and the
Road Landscape Manual, Main Roads 1998). • accommodate a change in the batter slope or
batter material;
The appropriate top and toe of batter
surroundings, relative to the road shoulder and to • provide maintenance access, and
the natural terrain, are based on the following • catch falling debris from the batter face.
assumptions:
The normal width of a bench is 5.0m (with a
• the 85th percentile angle of departure from the minimum of 3m), the edges of which should not
roadway by an errant vehicle has been assumed be rounded (see Figure 7.19).
to be 22° (average).
Benches are sloped away from the carriageway
• the batter slope is suitably compacted and and drained towards the ends of the cutting. The
graded, and free of obstacles that may cause longitudinal grade of the bench must be
vehicle snagging. determined in conjunction with the necessary
Figure 7.16 provides the dimensions to be used. erosion control measures.

September 2004 7-43

 Chapter 7: Cross Section Road Planning and Design Manual

Figure 7.15 Batter Slope Treatments

Hinge Point *

8m

Formation
(including verge 2
and rounding) * on
1

Level

1 on
4

* See Figure 7.7

Superimposed Cross Sections

Figure 7.15 (a) Transition of Batters from Bank to Cutting

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Road Planning and Design Manual Chapter 7: Cross Section

Figure 7.16 Desirable Crest and Sag Roundings

September 2004 7-45

 Chapter 7: Cross Section Road Planning and Design Manual

N.B. • Only suitable for batters

between 1 on 3 and 1 on 1.
• Flatter batters should be
treated by contour ripping
and top soiling.
• Steeper batters require
special treatment.
• NOT to be used in dispersive
soils.

Figure 7.17 Treatment of Cut Batters for Revegetation

7-46 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Source: RTA (1993)

7
Rock Armouring Alternative to Fill Slope

Benching

Planting at the Base of Steep Slopes

Visual Effect of Steep Cut Slope Straw Mulching

Figure 7.18 Alternative Treatment for Batters (Source: Road Landscape Manual)

September 2004 7-47

 Chapter 7: Cross Section Road Planning and Design Manual

Where visibility benching is required, the should not exceed 1m.

preferred treatment is to include the bench as a
widened table drain with a flat bottom at least 1.8 The minimum longitudinal grade in an unlined
m wide. (Refer to Chapter 9 for more details on table drain is 0.5%. However, flow velocities in
visibility benching.) unlined table drains should not exceed 1m/s.
Velocity of flow must be limited to this or lining
See also 7.11.2. will be required.

The arris formed by the side of a table drain and

7.8.5 Rock Fall Protection the shoulder should be rounded to minimise

7 Where there is potential for rock falling from the

face of a cut batter on to the road surface, action
damage to errant vehicles.

Lined table drains should be used in place of

to prevent the rock from rolling on to the surface unlined drains for grades less than 0.5%
of the road is required. A table drain with a base at (minimum 0.2%), or where velocities are likely to
least 1.8m wide would normally be adequate. cause scouring (1m/s or greater). Lined table
drains may be formed in the shape of the Type 28
However, where a table drain of inadequate width gutter as shown on Figure 7.21 or specially
is to be used, the road should be protected with a designed to suit the conditions.
chain wire fence erected outside the shoulder edge
behind the kerb delineating the shoulder. Figure On both the nearside and the offside of each
7.19(b) illustrates this requirement. carriageway in a cutting, a 1.0 m wide Type 28
drain will be provided if the drain falls within the
shoulder. Where superelevation is provided it will
be permissible for the water on the off side to run
7.9 Drainage straight into the median. However, consideration
is to be given to the provision of a Type 28 drain
7.9.1 Table Drains on the offside edge.

Table drains are located within the verges in

cuttings. Their purpose is to collect surface water 7.9.2 Catch Drains and Banks
draining from the carriageway and adjacent cut
batter, carrying the water to a suitable point of Catch drains are located on the high side of
discharge beyond the cutting. The invert of the cutting slopes behind the batter rounding. Their
table drain must be lower than the pavement sub- purpose is to intercept the flow of surface and
base to allow efficient drainage of the pavement seepage water within the upper soil layer to
layers. prevent erosion of the batter face.

Flat bottomed table drains (1.8 m wide for ease of Catch drains should be constructed to have a
maintenance) are preferred. However, this should rounded or trapezoidal cross section (see Figure
not be accomplished at the expense of making the 7.20), rather than a ‘V’ shaped cross section
cut batter steeper than 1 on 3. Erosion is less in (which are subject to erosion).
flat bottomed channels and some advantage is
gained even if 1.8 m cannot be achieved. A Depending on the runoff velocity, catch drains
minimum total verge width of 2.0m (see Figure should be stabilized immediately by seeding,
7.7) provides space for a mower to operate. For turfing, planting in conjunction with jute mesh,
the worst case, the residual grass length will be bitumen, masonry, rock mattresses or concrete
90mm longer on one side. lining. Where an un-lined drain is to be used, the
designer must consider both the long term
If it is necessary to deepen the table drain, the performance of the treatment AND the likely
cutting should be widened so that the maximum 1 performance of the treatment during the
on 4 side slope is maintained. Desirably the depth establishment period.

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Road Planning and Design Manual Chapter 7: Cross Section

Road Boundary

CatchBank
(Preferred Treatment)

For Detail
Channel may need see Figure 7.20
to be lined to avoid

7
erosion
5.0m
(min 3m)
Bench drained to
ends of cuttings

1 on 10

2-3m up to max.
of 7m, or as required

Figure 7.19 Location of Benches in Cuttings

3/4mm helicoil cablewire

Terminal posts All posts to have
Std. galvanised (Type B)
50 NB galvanised pipe weather caps (knuckle / knuckle) chainwire
mesh. 50 x 2.5mm
M10x90
galvanized
1200

hexagonal
50

bolt & nut.

450 350
Drill 12 dia. Galvanized Steel
75 hole in Sleeve
225 Intermediate posts Fix chainwire and cablewire post and 65 NB (50 NB post)
Stay posts to end panels 40 NB galvanised pipe in accordance with manufacturers’ sleeve 50 NB (40 NB post)
galvanised pipe recommendations. forbolt. 40 NB (32 NB Stay)
both sides with 32 NB 5.00 CENTRES
and every 5th panel on
CHAINWIRE FENCE
1.0

1
Traffic Lanes Shoulder 1.5
2.0 2.0

"S"
1
1%
Chainwire Fence
(see detail)
0.7 min

0.05

0.3

Figure 7.19(b) Rock Fall Protection

September 2004 7-49

 Chapter 7: Cross Section Road Planning and Design Manual

In areas where the catch drain is susceptible to They are spaced at intervals which meet the
scour, the surface water should be intercepted maximum flow width criteria. The location and
using a catch bank placed on the natural surface design treatment of batter drains are detailed in
on the high side of the batter point. There is no the Road Drainage Design Manual (Main Roads,
excavation of the surface to provide the earth for 2001).
the bank or to create the drain. The natural surface
is therefore not disturbed and not exposed to
erosion to the same degree. 7.9.5 Kerbs, Channels and
Access Chambers

7 7.9.3 Dykes Kerbs are used to separate areas used by vehicles

from areas used by other modes of transport, or
A Dyke is a low, longitudinal mound of earth, areas to be put to other uses. Channels are used to
asphalt or concrete, provided near the edge of collect and convey surface drainage to a discharge
embankments when it is required to protect the or collection point. Kerbs and channel are usually
batters from erosion, by controlling the water combined but may be used as separate elements.
movement off the road pavement surface. It is Stability of a kerb only element may be an issue
located under the guardfence on the lower side of where the kerb can be impacted by traffic since it
the pavement crossfall. Location of the dyke with can easily be knocked out of alignment.
respect to the face of the guardrail is critical for
safety reasons. (See Chapter 8.) The main purposes of Kerb and Channel are to:

• Provide lateral support to the pavement;

7.9.4 Batter Drains • Collect surface drainage and convey it to a point
of discharge;
Batter drains are provided on embankments to
transport the water from dykes to the bottom of • Manage a level difference between the footpath
the batter. and the carriageway;

Figure 7.20 Typical Catch Drains

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Road Planning and Design Manual Chapter 7: Cross Section

• Act as a longitudinal delineation of the edge of • provide adequate clearance to mountable or

carriageways; semi-mountable kerbs if used adjacent to high
speed carriageways;
• Separate carriageways from pedestrian and
cyclist areas; and • avoid or minimise kerbing near safety barriers
to improve safety (details of clearances
• Reduce the width of cuttings by substituting an required are given in Chapter 8);
underground drainage system for the usual table
drains. • include 1.5 m (min.) transitions to change from
one kerb type to another (semi-mountable to

7
The principal types of kerb are: barrier; new kerb to existing of a different
shape);
• Barrier - face sloped at 1 on 0.25;
• adopt 450 mm channel where kerb and channel
• Semi-mountable - face sloped at 1 on 1.5; and is required unless special circumstances apply;
• Mountable - face sloped at 1 on 7.5. • provide 50 mm Asphalt Allowance for all
barrier and semi-mountable kerb not installed
Barrier kerb has been used to provide a measure of
on a concrete pavement where the traffic
protection to pedestrians adjacent to traffic lanes
volume is expected to exceed 10,000 veh/day
and it encourages drivers to steer clear of the kerb.
within the design life of the project;
It is therefore an appropriate type of kerb to use on
inner city streets where pedestrians are in • use kerb that includes a backing strip in areas
significant numbers and speeds are low. subject to mounting by overdimensional or
heavy vehicles;
Barrier kerbs should not be used on high-speed
roads, as it is more likely to trip and overturn a • ensure that all grates located adjacent to sealed
vehicle that is out of control. These kerbs should be shoulders or bicycle lanes are bicycle safe in
avoided on the outside of low radius curves as it accordance with Australian Standard AS3996.
can contribute to truck rollovers. If kerb and
channel is essential in these cases, sufficient In general, access chambers should be located
clearance to avoid the outwards tail swing of large clear of the carriageway. This provides for easier
trucks (check with VPATH) must be provided. construction of the pavement and removes a
source of potential maintenance problems. It is
Semi-mountable kerbs are the standard type of also safer for workers using the access chambers.
kerb and channel used for delineation and
drainage on all intersections. Where it is not possible to locate the access
chamber clear of the carriageway, it should
Mountable kerb is suitable for the outside of preferably be placed in the parking lane. The case
curves on interchange ramps, on the approach of existing access chambers located in the
noses of exposed islands and for the separation of carriageway is discussed in Section 7.5.2.
normal traffic lanes from special areas intended
for use by over-dimensional vehicles in medians
or roundabouts. 7.9.6 Floodways

Figure 7.21 shows the standard shapes, dimensions

General
and applications of kerbs and/or kerb and channel
that may be used. Designers should use the most Where floodways are used, it is desired to provide
appropriate kerb type for the specific project. reasonable uniformity in selecting floodway
widths throughout the State without limiting
Designers should:
consideration of particular features of one site or
• avoid barrier kerb adjacent to high speed locality in arriving at the appropriate design.
carriageways;

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 Chapter 7: Cross Section Road Planning and Design Manual

Width Range (see Section 7.2.2).

Long Floodways: The following points refer to Short Floodways: Where the floodway is short
floodways comprising more than an isolated dip and confined to a main flow channel, especially
(the usual case of a floodway taking flood channel where sight distance is close to the minimum for
flows): the operating speed of the road, consideration
should be given to providing a full formation
• The general minimum formation width should width floodway.
be 8.6m, with some relaxation possible on
roads under 150 veh/day; Safety Barriers/Bridge Rails

7 • The general maximum formation width should

be 10.0m, unless the additional costs of
Safety barrier will reduce the efficiency of the
floodway in times of flood, but may be desirable
achieving full formation width are not from the point of view of traffic safety at other
significant; times. Whether safety barrier should be installed
in a particular case should be determined locally,
• The minimum shoulder protection should be
but where associated with a bridge structure:
1.0m;
• when the bridge is full floodway width, and the
• The maximum shoulder protection should be
main channel is shallow, consideration should
1.5m;
be given to omitting bridge rails and safety
• The balance between pavement widening and barrier. However, road edge guide posts may be
shoulder width should be determined by local provided on the floodway with reflectorised
conditions. In the general case where shoulder hazard markers at the bridge abutment;
protection is more expensive than paving
• when the bridge is narrower than the floodway
material, the former would tend to the narrower
or the channel is deep it may be desirable to use
limit. In more remote areas where paving
rails with at least the minimum length of safety
material can be more expensive than an
barrier on the floodway approach to the bridge.
“adequate” material for cement treated
The conflict of goals i.e. delineation as against
shoulders, the reverse would occur.
obstruction in flood time cannot be determined
The above criteria lead to Table 7.16 of width by a general policy but must be decided locally
ranges related to pavement and shoulder widths by consideration of the specific case.

Table 7.16 Width Ranges

Pavement Shoulder Formation Floodway (m)

Width (m) Width (m) Width (m) Elementary Total
Widths Width
4.0 2.5 9.0 7.0 + 2 x 1.0 to 9.0
7.0 + 2 x 0.8 8.6 (1)
6.0 1.5 9.0 7.0 + 2 x 1.0 9.0
6.0 2.0 10.0 7.0 + 2 x 1.5 to 10.0
8.0 + 2 x 1.0 10.0
6.5 1.5 9.0 8.0 + 2 x 1.0 9.0
6.5 2.5 11.5 8.0 + 2 x 1.0 9.0
7.0 2.0 11.0 8.0 + 2 x 1.0 10.0 (2)
7.0 2.5 12.0 8.0 + 2 x 1.0 10.0 (2)
NOTES:
1. The general minimum formation width is 8.6m. However, on lightly trafficked roads at the discretion of the District Director this
may be reduced to 7.4 or 8.0m.
2. The general maximum is 10.0m. However, where the cost of maintaining the larger width across the floodway is not excessive,
the full width may be maintained at the discretion of the District Director.

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Road Planning and Design Manual Chapter 7: Cross Section

7.10 Bridges and Clearances • For bridges shorter than 20m in length - the
carriageway width (see section 7.2 and 7.3 for
7.10.1 Road Bridge Widths the elements of width);

• For bridges longer than 20m - the width of the

Bridges comprise a relatively small proportion of
traffic lanes plus 1.0m clearance each side.
the total road length, but they are proportionally
much more expensive. They do, however, have a
much longer life than other elements of the road
structure and the width determined for a bridge

7
should be based on a longer period of traffic
growth than for other elements.

Bridge widths shall be determined from Table

7.17 or from Table 7.18. Departure from the
indicated widths may be required to satisfy
particular situations.

For example, if the bridge is located in or near

built-up areas, or is part of a local or regional
cycle route, it will need to be designed to
accommodate cycle and/or pedestrian traffic. This
may be in form of wider shoulders or a separate
pedestrian facility on one or both sides of the
bridge.

On roads with significant numbers of road trains,

sufficient width is required to allow two road
trains to pass safely. This will be particularly
important if the bridge is on a curve.

The widths for National Highways shown in Table

7.17 are derived from the published Standards and
guidelines for National Highways:

• For lengths less than 20m - the carriageway

width (see sections 7.2.5 and 7.3.7 for the
elements of width);

• Where the AADT across the bridge is expected

to exceed 1000 per lane within 20 years of the
works being opened to traffic - the width of the
traffic lanes plus 2.4m; and

• For all other cases - the width of the traffic

lanes plus 1.2m.

In all cases, the needs of cyclists must be

considered and appropriate allowance made.

The widths for roads other than National

Highways shown in Table 7.18 are based on the
following approach:

September 2004 7-53

 Chapter 7: Cross Section Road Planning and Design Manual

TYPE TYPICAL USE PROFILE AND DIMENSIONS

A
C

40
25
R25

215 min.
R25
1 Mountable

150 min.
300

7
A B
300 300 C

40
65
R25
2

215 min.
Mountable with channel

150 min.
Bullnose 10 Chamfer 25

600

50 230 50 230 50
R5 R5
Channel: C

115
R25 R25
265 min.

3 Medians and

150 min.
R25
Table Drains

610

A
Barrier on road surface: 40 110 40

Dykes; R25
4
150

Islands and median

edges at pedestrain
crossings and signals. 190

A
110 40
R5

R25 C
150

Barrier below road surface:

5
200 min.

As for 4

150

A B
110 40 300 or 450

6 R5 C

(300ch) Barrier Kerb and channel:

R25
40
150

R25
&
150 min.

7 As for 4
(450ch)
450 or 600

REFERENCE POSITIONS: A Line of kerb B Line of channel C Height reference

Figure 7.21 Standard Kerb Shapes

7-54 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

TYPE TYPICAL USE PROFILE AND DIMENSIONS

A
8 Semi Mountable kerb on 110 190 DETAIL x

road surface:
& R25

125
R225
9 Medians and Islands; R25

(with AA) embankment margins. 300

'AA'

7
C

Semi Mountable kerb: A

DETAIL x
300 190
10
Backing strip on road surface R25
& R225

125
R25
11 As for 8 & 9 where over 490
'AA'
(with AA) dimensional vehicles C
traverse kerb.

A
110 190

12 Semi Mountable kerb R25

125
R225
& below road surface
R25

13 'AA'

150 *
(with AA) As for 8 & 9 C

300
* min. depth below
road surface.

A B
110 190 300 or 450
C
14 Semi Mountable kerb
40

R25
125

(300ch) and channel: R225 R75

&
150 min.

15 Parking lanes, medians where Chamfer 25

(450ch) drainage required.

600 or 750

WITH CHANNEL

Channel or tray

16 600 as specified in
the scheme
300 300
(300 ch documents
15

or Ramped vehicular
crossing:
tray) &
125
260 min.

17 Accesses to property
150 min.

(450 ch
or tray)

R25
10

“AA” = Asphalt Allowance

DETAIL X

Figure 7.21 Standard Kerb Shapes

September 2004 7-55

 Chapter 7: Cross Section Road Planning and Design Manual

TYPE TYPICAL USE PROFILE AND DIMENSIONS

18
(*BK & 300 ch
or tray)
Channel or tray
Barrier kerb shown. Details similar for semi mountable kerb as specified
19 in the scheme
documents

7
(*BK & 450 ch 1 on 8 m
ax. #
or tray)
Ramped pedestrian

80 min.

150 min.
crossing
20

4 5°
(*SMK & 300 ch 100
or tray)

* BK = Barrier Kerb
21 * SMK = Semi Mountable Kerb
(*SMK & 450 ch # Max. ramp slope for wheelchair access shall be 1 on 8.
or tray)

R75
1 on 12 1 on 12

Channel Adjacent to R15

175 min.
25
150 min.

22 shoulders
300 300

A B
110 40 300 or 450
R5
23 Barrier Kerb and Tray:
Gradient 3%
C
(300 tray) R25
150

& R25
Medians and Islands
24
#
150 min.

#9 (300 tray)
adjacent pedestrian 14 (450 tray)
(*BK & 300 ch crossings and signals
or tray) Chamfer 25
450 or 600

Figure 7.21 Standard Kerb Shapes

7-56 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

TYPE TYPICAL USE PROFILE AND DIMENSIONS

A B
25 110 190 300 or 450
Gradient 3%
(300 Semi Mountable Kerb C
tray) and Tray R25

125
R225
& R75

7
Medians and

#
26

150 min.
(450 Island Chamfer 25

tray) 600 or 750

# 9 (300 tray)
14 (450 tray)

A B Gradient 3%
300 300
C

65
R 25
27 Dished Crossing
215 min.

9
150 min.
Bullnose 10

Chamfer 25
600

500 500
100

Dished Crossing increased

28
min
150

waterway
1000

Figure 7.21 Standard Kerb Shapes

September 2004 7-57

 Chapter 7: Cross Section Road Planning and Design Manual

Table 7.17 Bridge Carriageway Widths - National Highways

Bridge Two Way One Way

Single Lane Two Lane Single Lane Two Lane
Length AADT Shldr Lane Shldr Width Shldr Lanes Shldr Width Shldr Lane Shldr Width Shldr Lanes Shldr Width
<20 <3000(a) - - - - 1.5 7.0 1.5 10.0 2.0 3.5 1.0 6.5 - - - -
<20 >3000(a) - - - - 2.0 7.0 2.0 11.0 2.0 3.5 1.0 6.5 2.0 7.0 1.0 10.0
>20 <1000/ - - - - 0.6(b) 7.0 0.6(b) 8.2 2.0 3.5 1.0 6.5 - - - -
lane

7
>20 >1000/ - - - - 1.2(b) 7.0 1.2(b) 9.4 2.0 3.5 1.0 6.5 2.0 7.0 1.0 10.0
lane

NOTES:
1. Wherever possible, bridge carriageway widths should equal the approach carriageway widths.
2. Use 3.0m shoulders adjacent to a barrier centreline marking or consider further widening to provide for auxiliary lane/s.
3. Add appropriate lane widths to the two lane configurations to determine multi-lane bridge widths.
4. All culverts are to be designed for full width of formation.
(a) AADT within 10 years, other AADT’s are within 20 years.
(b) Minimum allowable shoulder widths have been used.
5. If a bridge is part of cycle route and/or is in a built-up area, extra shoulder width will be required to allow adequate cyclist
access, and pedestrian facilities will be required.

Table 7.18 Bridge Carriageway Widths - Other than National Highways

Bridge Two Way One Way

Two Lane Single Lane Two Lane
Length AADT Shldr Lanes Shldr Width Shldr Lane Shldr Width Shldr Lanes Shldr Width
Any <100 1.0 6.0 1.0 8.0 0.6 3.0 0.6 4.2 - - -
Any 100-500 1.0 6.0 1.0 8.0 2.0 3.0 1.0 6.0 - - -
Any 500-1000 1.0 6.5 1.0 8.5 2.0 3.25 1.0 6.25 - - -
<20 1000-2000 1.5 6.5 1.5 9.5 2.0 3.25 1.0 6.25 - - -
>20 1000-2000 1.0 6.5 1.0 8.5 2.0 3.25 1.0 6.25 - - -
<20 >2000 2.0 7.0 2.0 11.0 2.0 3.5 1.0 6.5 2.0 7.0 1.0 10.0
>20 >2000 1.0 7.0 1.0 9.0 2.0 3.5 1.0 6.5 1.0 7.0 1.0 9.0

NOTES:
1. Wherever possible, bridge carriageway widths should equal the approach carriageway widths.
2. Use 3.0m shoulders adjacent to a barrier centreline marking or consider further widening to provide for auxiliary lane/s.
3. Add appropriate lane widths to the two lane configurations to determine multi-lane bridge widths.
4. All culverts are to be designed for full width of formation.
5. AADT’s are within 20 years.
6. If a bridge is part of cycle route and/or is in a built-up area, extra shoulder width will be required to allow adequate cyclist
access, and pedestrian facilities will be required.

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Road Planning and Design Manual Chapter 7: Cross Section

7.10.2 Pedestrian/Cyclist Bridges In general, shop awnings are to be set back a

minimum of 0.6m from the kerb face. Clearance to
The minimum vertical clearance to the underside awnings and buildings should be in accordance
of pedestrian/cyclist bridges over traffic lanes and with the relevant Local Government requirements.
shoulders is 5.5 m where the bridge is protected
by other structures or more generally 5.7m. Signs and associated support structures should be
However, due to their lighter structure, located in accordance with the MUTCD (Qld). In
consideration should be given to increasing this general, the sign face should be placed behind the
clearance to 6.0m, particularly at isolated sites. kerb face by a minimum horizontal clearance of

7
The requirements of Table 7.21 must be applied. 0.6m.
Vertical clearances over footpaths should not be
less than 2.4 m and desirably 2.5 m. Clearance
over cycleways should not be less than 2.4m. If a Table 7.19 Lateral Clearance to Fixed Objects

lower height is used, signs to warn users of the 85th Percentile Clear Zone Shy Line Width
low clearance should be installed. Speed Width (m)
(km/h) (m) Left Right
Handrails on bicycle bridges are to be in ≤70 3.0-3.5 1.5 1.0
accordance with Chapter 5, Section 5.5.5. 80 3.5-4.5 2.0 1.0
90 4.0-5.0 2.5 1.5
The minimum clear width of a pedestrian bridge
≥100 ≥4.5 3.0 2.0
should be 1.8 m. This width is adequate for the
passage of up to 300 people per hour and allows Note: Clear zones vary according to traffic volume -
must be assessed using Figure 7.12.
two wheel chairs to pass.

For shared bicycle/pedestrian bridges, the

minimum width is 3.0m. Where the volumes of (b) Working Width
pedestrians and/or cyclists is high, the two
functions should be segregated and the The working width is the lateral distance required
appropriate width for each function applied (see from the face of a rigid barrier to an element (such
Austroads, 1999). as bridge piers, walls etc.). See Figure 7.22.

Pedestrian and cyclist overpasses may need to be Table 7.20 gives suggested working widths
fully enclosed to prevent objects being thrown appropriate for different speed zones.
from them on to the roadway below.
A 4.3m high rigid and/or articulated vehicle was
used to determine the following working width
7.10.3 Lateral Clearance offsets, relative to impact speed and crossfall for
standard height rigid barriers only.
(a) Road

The lateral clearance from the edge of the Table 7.20 Working Widths
travelled way to bridge piers, abutments, retaining
walls and other fixed objects should conform to Speed Zone 0% x’fall 3% x’fall 7% x’fall

the requirements for clear zones (see Section 7.6). High - 100km/h 0.8 0.9 1.1
However, if the desirable clear zone cannot be Low - 60km/h 0.5 0.6 0.8
achieved and it is not possible to remove the
object from the clear zone (see Section 7.6), the
object should be made frangible or protected by As rigid barriers have no dynamic deflection, the
the installation of a traffic barrier, with attention vehicle inertia becomes an issue.
being paid to the shy line effect and working
width (see Section 7.2.1). Refer Table 7.19 for
lateral clearance to fixed objects.

September 2004 7-59

 Chapter 7: Cross Section Road Planning and Design Manual

When considering vehicles with high centres of 7.10.4 Vertical Clearance

gravity, the vehicle will pivot about the roll axis as
shown in Figure 7.22. Clearances are to be based on the ultimate cross
section using the method of measurement shown in
Figure 7.23. Minimum vertical clearances required
for different road types are shown in Table 7.21.
Consideration should be given to the use of
convenient alternative routes (e.g. using the ramps
of a diamond interchange) where a clearance of 6

7
m or more is required thus allowing a lower (and
presumably cheaper) bridge to be built.

Table 7.21 Minimum Vertical Clearances

Figure 7.22 Working Width
Description of Preferred Absolute
of Road Minimum Minimum
Very High Clearance 6.5m 6.0m
(c) Boundary Routes (where no suitable
convenient alternative is available)
The clearance of the road elements (hinge point of Highways and 6.0m* 5.5m*
batters) from the boundary of the road reserve has Motorways
to accommodate space for maintenance of the Declared Roads 5.5m* 5.5m*
road elements and frequently Public Utility Plant Other Arterial and Main Roads 5.5m* 5.5m*
(e.g. Communications cables, Gas pipelines). Other Roads 5.3m* 4.8m**
Noise barriers and cycle ways are placed in this
* Heights provide 300 mm resurfacing or pavement
space where it is convenient. strengthening to the major road, and 100 mm to
“Other Roads”.
The actual dimension of the clearance will depend
** Legal height of livestock and vehicle carrying
on all of these factors (if known) as well as the vehicles is 4.6m. Where it is likely that these types of
ability to acquire the necessary property. The vehicles will use the road, the minimum clearance
general minimum for all roads is to be 10m, with must be 4.8m.
15m adopted for motorways and major highways.
The absolute minimum width at restricted sites is
5m and this should be tolerated for short distances Signs are to be placed to provide a minimum
only - 5m provides for a maintenance vehicle to vertical clearance of 2.0 m when installed on
travel along the road boundary. In all cases, the footpaths and 5.5 m minimum for signs that are
minimum clearance to the edge of travelled way is located over a traffic lane. For overhead Public
to be the clear zone required, provided the clear Utility Plant, see Section 7.10.7.
zone is not to be used for pedestrian or cycle
movements - these movements are to be allowed
for outside the clear zone.

Note that it is not necessary to acquire additional

land for Public Utility Plant. These services are
required to acquire their own land but may be
permitted to use available space provided the
operation of the road is not compromised. Public
Utilities are not generally permitted to occupy
land on a motorway road reserve.

7-60 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

available. The access should be designed to cater

for the needs of sight-impaired people and the
necessary features to guide them incorporated.

Landscaping and services should be located so as

not to obscure sight lines. High quality, vandal
proof lighting will be required in subways to
enhance personal security. Murals can often be
provided to discourage graffiti.

Design should be in accordance with AS1428 and

Austroads, 1995a and 1999. 7
Cross Section

The desirable interior cross section for subways is

6.0m wide by 2.7m high (clear of light fittings,
signs and other equipment). In constrained
situations, a width of not less than 3.0m may be
NOTES: acceptable. The minimum clear height allowed is
1. Clear zone is speed related. 2.4m.
2. Vertical clearance for pedestrians is 2.4m.
3. Vertical clearance for cyclists is 2.5m. Walkway crossfall is to be not greater than 2.5%
4. Awnings set back 0.6m from kerb face. For bus with 2.0% preferred to cater for impaired users.
stops, where the bus must access the stop at a
steep angle, the clearance must be 0.8m. This 0.8m
Grades
clearance must be provided to all objects in the
vertical plane at these locations.
Longitudinal grades in the subway should be not
Figure 7.23 Roadway Clearances less than 0.3% in one direction to allow for
longitudinal drainage. The maximum grade in the
subway should not exceed 5%.

For access ramps, the maximum grade to be

7.10.5 Pedestrian/Cyclist adopted is 1 on 14 with landings at intervals not
Subways exceeding 6.0m. Landings should be not less than
1.5m x 1.5m in area.
General

Pedestrian subways are not the preferred method 7.10.6 Clearance to Railways
of providing for grade separated pedestrian
crossings. They are not favoured by pedestrians The relevant railway authority sets the clearance
and cyclists because of the potential danger posed requirements over railways. For Queensland Rail,
by the “hidden” nature of the crossing. However, their drawing No. 2231, included here as Figure
it is sometimes the case that a subway is the only 7.24, gives the requirements for particular
reasonable alternative. circumstances. However, it is imperative that it
is understood that this is to be used as a guide
Subways should be lit and care taken with the
only and actual clearance requirements at a
design to ensure that “hiding” places do not occur.
particular site must be determined in
There should be a clear line of sight from one end
consultation with Queensland Rail.
to the other and this should preferably be available
from the adjacent street. Access should be by The actual clearance allowed will depend on
means of ramps or a combination of ramps and specific site parameters such as future track
stairs provided that wheel chair access is fully requirements, track geometry and overhead

September 2004 7-61

 Chapter 7: Cross Section Road Planning and Design Manual

electric traction geometry. In addition, a number design, construction and maintenance activities
of design and construction issues will need to be should give priority to keeping moisture out of the
addressed. These include: roadway rather than assuming it will enter and
providing measures to remove it. This principle is
• Impact loads; different from that usually adopted for wet areas
and it is important to distinguish the difference.
• Erection methods and procedures;
Some moisture will of course enter the roadway,
• Temporary clearances during construction; and
but the amount and its effect can be minimised

7
• Safe working on Railway property. and kept clear of the wheel path locations. This is
achieved by a combination of:
Other issues may have to be considered in
addition to these at a particular site. • moisture control;

As these issues can have a significant impact on • pavement material properties;

the whole design of the facility, it is imperative
• type cross section.
that they be addressed at the concept stage of the
design. Advice should be sought from the This section deals with the type cross section only.
Manager Civil Engineering, Queensland Rail, as
early as possible in the process. Figure 7.25 illustrates an unacceptable situation
for design through expansive soil areas.

7.10.7 Public Utility Plant Figure 7.26 illustrates the desirable type cross
section features outlined in the following
Clearances to overhead Public Utility Plant discussion.
require special consideration. They vary from
utility to utility and for classes within a utility Shoulder Protection
(e.g. electricity mains) depending on the specific
Even with the best low permeability/adequate
feature under the overhead service and the
strength paving materials, moisture will still enter
characteristics of that service.
the roadway and produce edge effects of
The requirements of the Authority involved pavement and subgrade weakening to about one
should be established at the Concept and Planning metre in width. Best performance will be achieved
stages of a project development. Table 7.22 is by providing at least one metre of sealed
provided as a guide to the clearances to be pavement outside the edge of the wheelpath. The
expected. wheelpath position should be determined from
observations taken of at least 100 heavy vehicles
Horizontal allocation of space for underground on roads of similar traffic volume and
services is described in Section 7.5.2. composition, type cross section and alignment.
Consideration of any different edge and centre
line marking is required. Additional lane width
7.11 Special Considerations may be required on crests and curves to allow for
different wheelpath positions due to visibility
7.11.1 Roads on Expansive Soils restrictions and vehicle tracking characteristics.
in Western Queensland
Encased Pavements
In order to obtain best performance, it is important
When the traffic lanes and shoulders are fully
to take advantage of the low average rainfall and
sealed, moisture can still be absorbed by
normally short rainfall durations of the western
pavement material exposed on the batters. Large
areas. The relatively low traffic volumes also help
exposed areas will create problems even with low
to lessen impacts on the road performance. All
permeability materials. Situations to avoid

7-62 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

include excess pavement width beyond the seal, The current pavement depth design process does
loose pavement spilled or graded down the batters not appear to replicate the observed road
and very flat pavement batters. These can be performance. Further development is needed to
overcome by cutting the pavement batter to 1 on 2 provide an improved pavement design process.
at the seal edge, removing excess pavement However, issues other than depth are important.
material and encasing the pavement with
embankment at a 1 on 4 slope. Good compaction Sealed Pavement Batters
at the pavement edge is important to minimise
Sealed pavement batters have been used on a
moisture entry.

7
number of jobs in conjunction with very
Even more positive encasement can be provided permeable base materials. They reduce the
by adding 300 to 500mm of embankment on both severity of moisture entry but will not eliminate it.
sides of the formation. Spraying bitumen (without The more uniform conditions created will reduce
cover aggregate) on the top 300mm of the roughness increase rates and extend pavement
pavement batter before encasing would further life. Disadvantages include increased construction
improve performance, particularly in the first few and reseal costs, and damage from traffic and
years. maintenance operations. Their use as a long term
measure is not recommended universally, but they
Road sections constructed initially or through have a possible use as a corrective treatment on
subsequent maintenance with encased pavements existing permeable pavements.
have been found to have substantially less edge
heave and roughness increase rates. This is Batter Slope and Formation Height
attributed to reduced moisture infiltration and
evaporation and the greater uniformity obtained. Flat embankment batters and low formation heights
should be used whenever possible as these will
Pavement Depth minimise moisture changes below the pavement.

Thin pavements have been shown through Batter slopes of 1 on 4 or flatter should be used on
computer simulation and monitoring of all fills up to 2m. The formation needs to be a
instrumented pavement sites to absorb less positive height above the surrounding terrain but
moisture than thicker pavements. With the kept as low as possible (say 300 - 500mm at the
resultant stronger subgrade and more appropriate top of pavement at formation edge).
traffic loading distribution assessments, these
pavements can carry much more traffic than the Longitudinal Drainage
current pavement design procedures attributed to
In flat country, table drains should never be
them.
constructed as they will hold water for extended
Pavements as thin as 100mm have been used but periods and adversely affect road performance.
are not recommended because of construction Where existing table drains occur they should be
tolerances, compaction difficulties and the risk filled with embankment. In addition, flatter
from severe damage from heavily overloaded batters can be used to keep any ponded water
vehicles. However, many pavements of 250mm further away from the road. Diversion drains to
and even 150 and 200mm have performed well. nearby borrow pits can also help.
There appears to be no advantage in using depths
On gentle grades, table drains may be used to
greater than 250 to 300mm.
minimise earthworks where positive drainage
In addition to the above advantages, a single occurs, provided erosion is not an issue. They
pavement course (or at most two courses) will should be used in cuttings but long shallow
conserve material resources, save costs, reduce cuttings should be avoided particularly where
longitudinal crack widths and shorten grades are nearly flat. A table drain depth of
construction time. The latter will provide other 300mm is suggested with flat bottom drains used
benefits in decreasing exposure to excess rainfall. if excessive siltation is a problem.

September 2004 7-63

 7

7-64
PRESCRIBED L.V. CONDUCTOR H.V. CONDUCTOR
CATEGORY LOCATION DESCRIPTION DISTANCE NEUTRAL SCREENED L.V. L.V. >1000V >33kV >66kV >132kV >275kV >330kV
INSULATED SERVICE LINE INSULATED UNINSULATED <33kV <66kV <132kV <275kV <330kV <500kV Table 7.22
At centre line of carriageway Vertically 5.5m 5.5m 5.5m 6.7m 6.7m 6.7m 7.5m 8.0m 9.0m
At other positions Vertically - 5.5m 5.5m 5.5m 6.7m 6.7m 7.5m 8.0m 9.0m
ROADS
At kerb line Vertically 4.9m - - - - - - - -
MINIMUM At fence alignment Vertically 3.7m - - - - - - - -
Private driveways & elevated Vertically 4.5m 5.2m 5.2m 5.5m 6.7m 6.7m 7.5m 8.0m 9.0m
vehicle access
Chapter 7: Cross Section

CLEARANCE
Areas not normally used by
Vertically 2.7m 5.2m 5.2m 5.5m 6.7m 6.7m 7.5m 8.0m 8.0m
vehicles
FROM
Land that, because of the
OTHER
steepness or swampiness of its
GROUND Vertically - 4.5m 4.5m 4.5m 5.5m 5.5m 6.0m 6.7m 7.5m
terrain, cannot be crossed by
traffic or mobile machinery
Road cuttings, embankments &
Horizontally 1.5m 1.5m 1.5m 2.1m 4.6m 4.6m 5.5m 6.0m 7.0m
the like
Unroofed terraces, balconies,
sundecks etc, subject only to Vertical Above 2.4m 2.7m 3.7m 4.6m 5.5m 5.5m 5.5m 7.0m 8.0m
pedestrian traffic with surrounding
Vertical below 1.2m - - - - - - - -
handrails etc., on which person
MINIMUM
may stand Horizontally 0.9m 1.2m 1.5m 2.1m 4.6m 4.6m 5.5m 5.5m 6.0m
CLEARANCE Roofs or similar structures not Vertically 0.5m 2.7m 3.7m 3.7m 4.6m 4.6m 5.5m 5.5m 6.0m
used for traffic or resort &
FROM surrounds on which a person may Horizontally 0.2m 0.9m 1.5m 1.5m 4.6m 4.6m 5.5m 5.5m 6.0m
stand
Covered places such as
STRUCTURES verandahs, balconies & windows In any Direction 1.2m 1.2m 1.5m 2.1m 4.6m 4.6m 5.5m 5.5m 6.0m
which can be opened
Minimum Overhead Clearance to Various Utilities

& BUILDINGS Blank walls/windows which cannot

Horizontally 0.2m 0.6m 1.5m 1.5m 3.0m 4.6m 5.5m 5.5m 6.0m
be opened
Other structures not normally Vertically 1.2m 0.6m 2.7m 3.0m 3.0m 4.6m 5.5m 5.5m 6.0m
accessable to persons Horizontally 1.2m 0.3m 1.5m 1.5m 3.0m 4.6m 5.5m 5.5m 6.0m
Railway tracks (non-electrified
Vertically 7.6m 7.6m 7.6m 7.6m - - - - -
areas)
Electrified traction wiring &
- U.G. U.G. U.G. 3.0m - - - - -
supports (electrified areas)
RAILWAY Telegraph, telephones, stays,
signal lines & electrical lines 650V Vertically 0.6m 0.6m 0.6m 1.2m - - - - -
& below
Electrical lines over 650V to 33kV
Vertically 1.2m 1.2m 1.2m 1.2m - - - - -
excluding electrical traction wiring
Min-apron separation to telecom Refer Local Electricity Authority for Clearance
TELECOM
Stays In any Direction 1.0m 1.0m 1.0m 2.0m 2.0m 3.0m 5.0m 5.0m -

Notes
1. All information from: Electricity Regulations (QLD 1994); Draft Agreement for Overhead & Underground Electric Lines crossing Railways in Queensland, 1988; Code of Practice for Overhead Power &
Telecommunication in-span Crossings.
2. Confirmation should be sought from Local Electricity Authority regarding the above clearances or voltage of conductors.
3. These are clearances allowed by the Authorities involved. The clearances specified in Table 7.21 are adopted where they exceed those in this table.
4. Allowance for temperature effects on the dimensions of overhead cables must be included.
5. For Communication Lines (Telephone and Cable Television), adopt the requirements for Neutral Screened Insulated Service Line.
Source: Standard Drawing 1333

September 2004
Road Planning and Design Manual
Road Planning and Design Manual Chapter 7: Cross Section

Figure 7.24 Required Clearances for Proposed Structures

September 2004 7-65

 Chapter 7: Cross Section Road Planning and Design Manual

Overwidth pavement or
unsealed shoulder
Exposed pavement batter with
loose surface on a flat slope

Loose excess pavement

material

7 Water ponded in table

drain

Thick permeable
pavement

Figure 7.25 Unacceptable Features (Expansive Soil)

0.5

CL 1 on
4
or fla
# tter
Shoulder protection 1.0 Bitumen seal ALTERNATIVE
(FOR BETTER
ENCASEMENT)
Traffic lanes-6.0,6.5 or 7.0m
# # No table drains
Avoid long (Refer note 1.)
in flat country
shallow cuttings
Wheelpath Excess pavement trimmed
wander
back to a 1 on 2 slope
0.3

and encased with

1o
n2 3% embankment
3%
4
1 on 1 on
or fla
4 H (Refer note 2.)
Thin low tter
permeability
Table drains to have pavement
positive drainage.
Provide flat bottom
(preferred) A. 2 LANE ROAD
CL

Bitumen seal

Traffic lane-4.0 NOTES: 1. Traffic lane widths to suit vehicle

# # numbers and composition. Additional
width on crests and curves as required.
2. Formation height 0.3-0.5m wherever posible.
3. Single lane road to be widened to two
lanes where visibility is limited.

B. SINGLE LANE ROAD

(Refer note 3.)

Figure 7.26 Desirable Type Cross Sections (Expansive Soils)

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Road Planning and Design Manual Chapter 7: Cross Section

Table 7.23 Checklist for Cross Sections on Expansive Clays (not for floodways, perched water tables or
close to ponded water)

Feature Details
Wheel Path Positions • Determine OWP position for similar road, traffic volume and composition,
type cross section and alignment
Shoulder Protection • Provide 1m min sealed shoulder protection outside edge of OWP
Crests and Curves • Adjust widths on crests and curves if appropriate
Encased Pavement • Provide fully encased pavement with no exposed surfaces
Pavement Depth • Provide thinnest pavement that will carry the traffic
Batter Slope
Formation Height
• Keep batters 1 on 4 or flatter (up to 2m high)
• Keep formation edge height 300 to 500mm at top of pavement wherever
possible
7
Table Drains • Avoid table drains in flat country
• Provide 300mm deep table drains where positive drainage is available
• Avoid pondage of water within 5m of the formation for extended periods
• Provide flat bottom table drain if excessive siltation is a problem
Permeable Embankment • Don’t allow the use of permeable materials
Existing Formation • Consider alignment options which include reuse of any existing formation

Zonal Use of Expansive Materials Construction costs and all other relevant factors
must be considered when deciding whether to
The zonal use of expansive materials to place them construct on the existing alignment.
in the embankment beyond the influence of
seasonal effects has application in higher rainfall Table 7.23 provides a check list summarising the
areas (Technical Note No.10 “Expansive Clay cross section design issues.
Embankments”). It is not considered practical or
necessary in western areas if the recommendations
of this technical note are followed. 7.11.2 Roads in Rainforest
(including Wet Tropics)
Permeable materials should never be used as
embankment or a selected layer over expansive Carriageway Widths
soils as the increased moisture entry will more
The width of the road should generally be based
than offset any advantages of an improved
on the traffic volume, the type of road being
subgrade.
designed, the speed of the traffic and the likely
Use of Existing Formation environmental impacts. (See 7.2, 7.3, 7.4 and 7.5.)

Construction on the line of an existing formation Other factors to consider include the following.
can be an advantage, provided sufficient
Providing carriageway widening on curves for
formation height is achieved, as it is liable to
larger vehicles is necessary. Adopting the
provide moisture conditions close to equilibrium.
minimum radius curves in steep terrain may result
However, good performance has also been
in the need to provide extensive widening for B
achieved on sections of new alignment. The issues
doubles and for sight distance. For instance on a
discussed in this section, together with moisture
50m radius curve a B double would require the
control and selection of pavement materials are
traffic lane to be widened to 6m.
considered to have a greater influence on
performance. A verge width may also need to be allowed to
provide for guard rail, verge drains and verge
berms on fill.

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 Chapter 7: Cross Section Road Planning and Design Manual

The single most important way to minimise In addition to clearing width, selection of cross
impacts of roads through tropical rainforest is by sections should consider the potential impacts of
reducing clearing width for as much of the road side cuts and batters, as in many circumstances
length as possible. Planning should therefore they become fauna barriers, in effect impassable
identify mechanisms to reduce clearing width as cliffs.
far as possible (such as use of barriers rather than
relying on clearing for the necessary recovery Table 7.24 provides some of the advantages and
width). disadvantages of the different carriageway types
and suggests areas where they may be used.

7
On scenic (tourist) 4WD roads or in World
Heritage Areas where one lane is desirable (taking It is important to note that best practice will
into account safety considerations), width can be involve the consideration of different cross
reduced by providing drainage on one side only sections over relatively short sections. As an
(crown shape has drainage each side). example, for environmental reasons divided two
lane carriageway may only need to be over a short
On new two-lane roads, it will rarely be possible distance to maintain connectivity of a particular
to achieve canopy closure. Alternative ways of habitat (eg. a riparian gallery rainforest, or a
providing connectivity will be required. steeper gully).

For high volume roads requiring four lanes or Road Formation/Earthworks

more, dual carriageways will be required. Four
lane (or more) undivided two-way roads are not The desired outcome is to minimise earthworks
acceptable for traffic safety reasons. In these and disturbance. An essential first step is to
cases, a dual carriageway, which enables retention integrate the design with the site and the design
of natural vegetation in a wide median may selected should be compatible with the natural
provide greater opportunity for fauna crossing the characteristics of the area (geological, soil,
road. Fauna then only has to contend with traffic landform and hydrological limitations).
from one direction over a shorter distance.
By designing roads which minimise the area to be
However, it is preferable to provide
cleared, the height and slope of batters and the
interconnectivity with short tunnels and long
volume of earthworks, the resultant road
bridges at suitable locations.
alignment will generally be a safe, cost effective
The typical cross-section adopted for the road and an environmentally sound project that
corridor will impact on the environment in a requires minimal ongoing maintenance.
variety of ways and may need to be varied along
Batters should be designed to a stable slope based
a route to minimise a particular impact. Generally,
on consideration of topography, soil type,
for two lane roads the minimum clearing widths
vegetation and rock formations for revegetation.
will produce the least impact.
Note, this must also consider needs to minimise
The cross section of roads through natural habitat erosion. Narrower total widths may be achieved
will need to be determined based on the by appropriate use of gabions, crib walls and rock.
conservation values requiring protection.
Consider rounding of batters and using constant
On local access tourist roads two single lanes batter line in less sensitive areas to provide a more
separated by a wider median may also have less natural cut/fill batter. The constant batter offset
impact than the two lane road. also better blends the earthworks into the terrain.

Importantly, the overall width of the disturbed On cuts, it is as important to ensure long term
road corridor is an issue requiring consideration. stability as it is to minimise construction
In general, minimising the overall width from disturbance. A steep cut which fails and collapses
cleared forest edge to cleared forest edge will will result in more disturbance and environmental
reduce the impact. impacts over time than a wider, less steep cut

7-68 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Table 7.24 Cross Section Suitability

Cross Section Type Advantages Disadvantages

and Suitability
Unsealed road Cheaper construction costs. As traffic volumes increase,
Suitable for low volume roads with maintenance costs increase
moderate grades. significantly along with erosion and
sedimentation.
In some circumstances provides Steep grades more readily eroded and
presentation opportunity and may require sealing.
“character”. May need to close to traffic during the

7
wet season.
Single lane sealed road Requires minimum width of disturbance. Requires widening at crests and curves
two way Cheaper solution than a 2 lane sealed for safety.
road. Unsuitable for high volume roads.
Suitable for low volume If in closed forest and narrow clearing, Unsealed verges may erode.
access roads only. may enable canopy connectivity to be
maintained.
Two lane carriageway, Requires minimum width for clearing. May be a safety concern with wrong
each way separated by way movements.
a wide median Enables canopy connectivity to be
Suitable for low volume maintained. Need to provide areas for passing
roads especially access disabled/parked cars (only on uphill
roads and tourist roads. Enables refuge area within the median side).
Note: this option has not for animals (whilst crossing).
been used in the wet With long lengths and medium traffic
tropics region, most likely In steep sidelong country this design volumes overtaking opportunities
application is for short will better match the terrain with less may need to be provided.
distances to meet specific height to cuts and fills.
environmental requirements.
Two lane, two way road Provide for some canopy connectivity For higher volume roads may require
if minimum widths adopted. passing lanes.
This is the normal road Generally less total width of As widths increase with traffic volumes
cross section for rural roads disturbance than two single canopy connectivity will be more
and is likely to be the usual carriageways. difficult to maintain.
solution in most cases. Cheaper to construct than two single Less gaps in the traffic stream than a
lane carriageways. divided carriageway.
Four lane divided Provides high capacity and overtaking Likely to be more expensive than a four
narrow median opportunities. lane undivided facility.
(New Jersey barrier)
May be an option where Provides increased safety and New Jersey barrier will prevent fauna
increased capacity and eliminates head on collisions. crossings across the road although if
safety is required on traffic volumes require a four lane
steep hilly sections and facility it is unlikely that sufficient gaps
the terrain precludes in the traffic stream will occur to enable
construction of a second animals to cross safely.
carriageway.
Four lane divided wide Breaks the total width into two parts May have a higher construction cost
median enabling some canopy connectivity to than a four lane undivided facility.
be maintained.
May be the preferred Total width of disturbance likely to be
solution in environmentally Breaks the traffic stream into two greater.
sensitive areas where the streams producing larger gaps for
median is forested. fauna to cross, however grade separated
fauna crossings are the preferred solution.
In steep sidelong country this will better
match the terrain.
Provides safer overtaking opportunities.
Prevents head on collisions.

September 2004 7-69

 Chapter 7: Cross Section Road Planning and Design Manual

which (although it has a greater area of retained and assist revegetation. (See Figures 7.17
disturbance during construction) is revegetated and 7.18.) Contour ripping and top soiling should
with surrounding vegetation species and regains be used where possible.
its habitat values.
The existing rainforest topsoil and humus should
The design of the batters should be coordinated be retained and respread on batters in the locations
with the environmental protection measures and from which it was stripped.
the landscaping design. Revegetating steep batters
is difficult and expensive and it may be better to Topsoil should not be transported from other areas
due to the possibility of importing exotic weeds

7
tolerate some additional disturbance in the short
term to achieve better revegetation in the long and/or plant pathogens.
term.
Note that in the Wet Tropics World Heritage
Cut and fill can have a major visual impact. The Area, apart from the cut and fill associated
area exposed during earthwork operations also with the earthworks, obtaining additional
can lead to erosion and sedimentation of material from borrow pits is prohibited unless
watercourses. specific approval has been obtained from the
Wet Tropics Management Authority. Dumping
The cut and fill can dominate the landscape and it material over the edge of batters is prohibited.
is desirable to minimise the earthworks as far as
practicable. Surface runoff damaging cut and fill batters should
be prevented. Catch drains, diversions banks and
The cut and fill transition zones should be channels above and below batters, and benches
designed so that they do not obstruct escape within them, will intercept surface runoff and
routes for any fauna. conduct it to safe disposal points. This will reduce
the hazard of sheet erosion and batter slumps.
The distant view of the road alignment should be
assessed and if major cuttings or fills will be Berms or benches are recommended on batters
visible then consideration may need to be given to with a vertical height greater than 5 metres. The
altering the alignment to avoid the cut being bench should be at least 1 metre wide, but
viewed from distant vantage points. Where the cut additional width may be necessary to allow for the
and fill cannot be avoided then revegetation of the movement of equipment used to establish and
batter should be given a high priority. maintain vegetation on the batters. However, this
may be avoided by progressively revegetating the
Various revegetation techniques are available from cut (hydraulic seeding and mulching) at the level
hydraulic seeding and mulching to planting with of each bench as the cut is excavated to avoid the
viro cells and spraying of freshly exposed rock with need for wide benches. If the batter is relatively
an activator that promotes moss and algae growth. steep (and it is unlikely to grow trees) a bench of
2-3m may allow trees to be established, this will
Water running over steep batters will develop a
effectively stabilise and screen the batter. (See
high velocity and resulting erosion of any
also Section 7.8.4.)
unprotected batter. Prevention of runoff water
running over batters is essential to prevent erosion. Benches should also be considered for batters
over 3m high to facilitate planting.
Consider the use of gabions or other retaining
devices in steep sidelong country (especially in Benches should have a maximum longitudinal
sensitive rainforest areas). grade of 1% if vegetated or 0.5% if paved. The
maximum grades should be restricted to a level
Incorporate surface relief on batter faces in the
consistent with the maximum permissible velocity
design to provide far greater microhabitat. This
for the type of lining used. A maximum cross
can be achieved by roughening cut slopes to
slope of 10% (1 on 10) on the bench towards the
provide horizontal steps along the batter or even
toe of the upper batter should apply.
small (300 mm) benching to enable topsoil to be

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Road Planning and Design Manual Chapter 7: Cross Section

With cut batters, a catch drain or diversion bank Creeks and streams are the principal corridors for
(preferred) should be constructed above the top of fauna movement in rainforest areas. Therefore the
the cut before excavation commences. Temporary road must be high enough above the stream to
toe drainage should be maintained as the work enable suitable fauna crossings to be installed in
progresses, with permanent toe drainage installed culverts or under bridges (see Chapter 3). Culverts
when the final depth is reached. To prevent requiring a concrete base should not be used in
erosion, a catch drain will require concrete lining. permanently flowing streams - they cannot be
constructed without causing major stream
For fill batters, permanent toe drainage should be disturbance.

7
installed prior to construction and should
discharge via a sediment basin to a suitable outlet. The cut/fill transition zone provides areas for
At the completion of each work period during the fauna crossings and barriers across these sections
construction of the bank, or at the onset of rain, a should be avoided.
windrow of suitably compacted soil material
should be constructed along the recently Consider using temporary retaining structures on
completed fill slope. fill (downhill slopes) to prevent downslope
contamination by spoil.
Early stabilisation of exposed batters is essential.
They should be adequately protected from erosion
by vegetation, or other means, within 4 days of 7.12 Typical Cross Sections
their construction. Best practice is to revegetate
all exposed areas immediately. The following pages show typical cross sections
which may be used as guides for design, although
In summary, the following principles of erosion
modifications may be needed to meet the
and sediment control should be incorporated in
requirements of each particular site.
the design:
• Figure 7.27 Two Lane Two Way Rural Road
• Integrate the project with the site;
• Figure 7.28 Multi Lane Rural Road
• Plan and integrate erosion control with • Figure 7.29 Undivided Urban Road
construction activities;
• Figure 7.30 Multi Lane Urban Road
• Minimise the extent and duration of
• Figure 7.31 Alternative Urban Arterial Road
disturbance;
Treatments
• Control stormwater flows onto, through and • Figure 7.32 Motorway Cross Section Elements
from the site;
Note that these figures are not necessarily drawn
• Use erosion control measures to prevent on-site to scale.
damage;
For routes accommodating multicombination
• Use sediment control measures to prevent off- vehicles (MCV), allowance has to be made for the
site damage; size of the vehicles and their tracking
charactristics. Appendix B sets out the minimum
• Stabilise disturbed areas quickly;
carriageway clearance widths for these routes.
• Inspect and maintain erosion and sediment Table B1 should be used in conjunction with the
control measures. following cross sections. The lane widths
indicated in the table and the following figures do
(For more detailed discussion, refer to not include allowance for curve widening. Where
Construction Site Erosion and Sediment Control - necessary, curve widening should be applied
Course Notes and Field Guide - References and according to Chapter 11, Section 11.10 “Curve
Other Reading.) Widening”.

September 2004 7-71

 7

7-72
Figure 7.27
Element Desirable Widths Reference
Lane (L) # 3.0m to 3.5m Table 7.4
Shoulder (S) 1.0m to 3.0m Table 7.7
Chapter 7: Cross Section

Verge (V) 1m (embankment) Fig. 7.7

2m (cutting) Fig. 7.7
Crossfall 2% - 4% Table 7.16 Road
Boundary
Lateral Clearance 5m - 15m Section 7.10.3
Road Reserve 40m (nominal)
Limit of Clearing 3m
Lateral Clearance
Note that appropriate clearances to public utility plant must be considered when
determining these dimensions. Allowance for access to the PUP is required. Limit of Clearing

# Note that lane widths do not incorporate any allowance for curve widening. Catch Point
Refer Chapter 11, Section 11.10 “Curve Widening”.

Carriageway

Safety Barrier V S L L S V Catch Bank

if required Fig. 7.20

Road Hinge Point

Boundary
Rounding Cutting
Batter Slope (1 on X)

Typical Cross Section of Two Lane Two Way Rural Road

Embankment
Batter Slope (1 on X)

See Figure 7.7

Limit of for Details
Catch Point
Clearing
Lateral Clearance

Road Reserve

September 2004
Road Planning and Design Manual
 Figure 7.28
Element Desirable Widths Reference
Lane (L) # 3.5m Table 7.4

September 2004
Shoulder (S) 2.5m* (left) to 1.0m(right) Table 7.7
Verge (V) 1.0m to 2.0m Fig. 7.7
Median 15m Sect. 7.4.6
Crossfall 2% - 4%
Rounding 2.0m(1.0m + 1.0m)
Lateral Clearance 5.0m - 15.0m Table 7.16
Road Reserve 90.0m(nominal)
Limit of Clearing 3.0m Section 7.10.3 Road
Road Planning and Design Manual

Boundary

2.5m sealed width required for cyclists where applicable. # Note that lane widths do not incorporate any allowance for Lateral Clearance
curve widening. Refer Chapter 11, Section 11.10 “Curve Widening”.
Note that appropriate clearances to public utility plant
must be considered when determining these dimensions.
Allowance for access to the PUP is required. Limit of Clearing

Median
Catch Point
Carriageway Carriageway

V S L L S Residual Median S L L S V

Safety Barrier

Typical Cross Section of Multilane Rural Road

if required Future Widening
Catch Bank
Catch Point Fig. 7.20
Road Rounding
Boundary Cutting
Batter Slope (1 on X)

Rounding
See Figure 7.7
for Details

Embankment
Batter Slope (1 on X)
Hinge Point

Limit of Clearing

Lateral Clearance

Road Reserve

7-73
Chapter 7: Cross Section

7
 7

7-74
Figure 7.29
Element Desirable Widths Reference
Traffic Lane 3.5m # Section 7.2.4
Parking Lane 3.0m* Section 7.2.8
Chapter 7: Cross Section

Channel (G) Up to 0.5m Figure 7.21

Footpath 3.5m Section 7.5.2
Road Reserve 20.0m(nominal)

* For shared use by parking and cyclists, the desirable width is 5.5m.
# Note that lane widths do not incorporate any allowance for curve widening.
Refer Chapter 11, Section 11.10 “Curve Widening”.

Road Road
Boundary Carriageway Boundary
cL

Footpath G Parking Traffic Lane Traffic Lane Parking G Footpath

Typical Cross Section of Undivided Urban Road

3% 3% 3%
3%

See Figures 7.9(a)&(b) for Typical high and low level

location of Public Utility treatments are shown in
services under footpath Section 7.5.1 & Figure 7.8

Road Reserve

September 2004
Road Planning and Design Manual
 Boundary Boundary

Road Reserve

Footpath G L = 10.5m (3 x 3.5m) 1.7m L = 10.5m (3 x 3.5m) G Footpath

Figure 7.30
0.5m 0.5m

September 2004
Restricted Access Road Reserve with Extruded Median Barrier
Road Planning and Design Manual

Road Road
Boundary Boundary

Road Reserve

Footpath G L = 10.5m (3 x 3.5m) Median L = 10.5m (3 x 3.5m) G Footpath

Right Turn Residual Median

Lane

Typical Cross Section of Multilane Urban Road

Median and Right Turn Lane
Road
Boundary

Element Desirable Widths Reference

Footpath Verge L = 7.0m (2 x 3.5m) Median Traffic Lane (L) 3.5m** Section 7.2.4
Channel (G) Up to 0.5m Figure 7.21
Median Variable Section 7.4 & Table 7.10
Grassed verge reinforced with Right Turn Lane 3.25m Section 7.2.9
lawn pavers or equivalent to Footpath 3.5m Section 7.5.2
withstand parking where required. Verge/Semi Mountable Kerb 4.0m Section 7.5.1
Road Reserve Variable

** NOTE: Lane widths on Bicycle Routes will vary according to

speed zone and AADT - Refer to AUSTROADS Guide
Services locate as in normal
to Traffic Engineering Practice Part 14 - Bicycles
footpath width (Second edition 1999 or later).
Note that lane widths do not incorporate any
Alternative Semi Mountable Kerb Cross Section allowance for curve widening. Refer Chapter 11,
Section 11.10 “Curve Widening”.

7-75
Chapter 7: Cross Section

7
 7

7-76
Figure 7.31(a)
Chapter 7: Cross Section

Element Desirable Widths Reference

Median 5.0m Section 7.4.3
Traffic Lane (L) 3.5m # Section 7.2.4
Parking 3.0m * Section 7.2.8
Channel (G) Up to 0.5m Figure 7.21
Clearance (C) Figure 7.12 Section 7.6.1
Planting 4.0m
Services & Pedestrians (SP) 4.0m Figure 7.9(b)

* If shared use by parking and cyclists, the desirable width is 5.5m.

# Note that lane widths do not incorporate any allowance for curve widening.
Refer Chapter 11, Section 11.10 “Curve Widening”.

Road Road
Boundary Boundary

Road Reserve

SP Planting C G Parking L = 10.5m (3 x 3.5m) Median L = 10.5m (3 x 3.5m) Parking G C Planting SP

Typical Cross Section of Urban Arterial Road - Mixed Function Type

Six Lane Divided with Parking

September 2004
Road Planning and Design Manual
 Figure 7.31(b)

September 2004
Element Desirable Widths Reference
Median 5.9m Section 7.4.3
Traffic Lane (L) 3.5m # Section 7.2.4
Shoulder (S) 3.0m Section 7.3.6
Road Planning and Design Manual

Channel (G) Up to 0.5m Figure 7.21

Outer Separator Table 7.15 Section 7.5.3
Service Road 10.0m
Footpath Table 7.13 Section 7.5.2

# Note that lane widths do not incorporate any allowance for curve widening.
Refer Chapter 11, Section 11.10 “Curve Widening”.

ROAD ROAD
BOUNDARY BOUNDARY

Road Reserve

Footpath Service Road Outer Separator S L = (3 x 3.5m) Median L = (3 x 3.5m) S Outer Separator Service Road Footpath

G G G G
G G

Six Lane Divided with Two-way Service Roads

Typical Cross Section of Urban Arterial Road - Separated Function Type

(in industrial area)

7-77
Chapter 7: Cross Section

7
 7
3.0m
Shoulder 3.5m 12.0m Median 3.5 Road
3.0m 1.5m 1.5m

7-78
Wire Rope Barriers 5% 1 on 10
Boundary
0.9m 0.6m Shoulder
2.4m 0.6m 0.6m 2.4m Noise

1
Shoulder Shoulder Barrier
Safety Safety

on
1

Figure 7.32(a)
Barrier Wire Rope Barrier
Safety Fence 0.1m gap for
1 on
'X' ' maintenance
1 on 'X
1o
n2
Chapter 7: Cross Section

Type 22 Channel
Type 28 Channel 0.6m 1.1m
Cut with Safety Barrier
Median Slope 'X' varies
(Restricted Sections) 1 on 10(min) - 1 on 3(max) Fill with Safety and Noise Barriers
Eight Lane Divided Motorway - 12.0m. median (Restricted Sections)
Road
Boundary

Cutting Traffic Lanes Traffic Lanes

Batter Slope (1 on X)

6.0m 3.0m 3.5m 3.7m 3.7m 3.5m 6.7m Median 3.5m 3.7m 3.7m 3.5m 3.0m 4.0m Road
2.0m Boundary
Shoulder Concrete Barrier Shoulder Rounding
3.0m 3.0m (Variable)
Shoulder Shoulder 2.0m
C
Rounding
1 on
2.0m
3
Crossfall Crossfall Crossfall Crossfall (Variable)

1 on
4(ma
x)
Type 22 Channel

* Note: Wildlife exclusion fencing is required on Eight Lane Divided Motorway - 6.7m. median*
the road boundary when using concrete
13.0m Clearzone (min)
barriers in the median (see Chapter 3).
3.5 Preferred Treatment in Fill
3.5m 15.0m Median

Typical Cross Section of Multi lane Motorway (No Transit Lanes)

Landscaped
2.4m 2.4m
Note: Cyclists have to be catered for Shoulder Shoulder
with a separate facility.

Control Line
Control Line

1 on 'X'
1 on 'X'

Type 28 Channel
Median Slope 'X' varies
1 on 10(min) - 1 on 3(max)

September 2004
Road Planning and Design Manual

Eight Lane Divided Motorway - 15.0m. median

 3.0m 1.0m Buffer 3.5m 7.7m Median 3.5m 1.0m Buffer 3.0m 1.5m 1.5m Road
Shoulder 5% 1 on 10
Boundary
Transit Concrete Barrier Transit Shoulder
0.9m 0.6m 3.5m 3.5m Noise
Shoulder Safety Barrier
Shoulder

1
Barrier

on
Safety Barrier

Figure 7.32(b)
0.1m gap for

September 2004
Crossfall Crossfall maintenance
1o
n2

Type 22 Channel 0.6m 1.1m

Type 22 Channel
Road
Boundary Cut with Safety Barrier
(Restricted Sections) Eight Lane Divided Motorway with Transit Lanes - 7.7m Median Fill with Safety and Noise Barriers
Road Planning and Design Manual

(Restricted Sections)
Cutting Traffic Lanes 3.5m 3.5m Traffic Lanes
Batter Slope (1 on X)
Transit Transit
Road
Boundary
6.0m 3.0m 3.5m 3.7m 3.7m 1.0m 12.0m Median 1.0m 3.7m 3.7m 3.5m 3.0m 4.0m
Shoulder Buffer Wire Rope Barriers Buffer Shoulder Rounding 2.0m
3.5m 0.6m 0.6m 3.5m (Variable)
Shoulder Shoulder 2.0m
Rounding
Wire Rope Safety Fence 2.0m
1 on
3
Crossfall Crossfall Crossfall
1 on Crossfall (Variable)
'X' '
1 on 'X
1 on
4(ma
x)

Type 28 Channel
Median Slope 'X' varies
1 on 10(min) - 1 on 3(max)
13.0m Clearzone (min)
Preferred Treatment in Fill
Eight Lane Divided Motorway with Transit Lanes - 12.0m Median
Note: Cyclists have to be catered for
with a separate facility. 1.0m Buffer 3.5m 15.0m Median 3.5m 1.0m Buffer
Transit Transit

Typical Cross Section of Multi lane Motorway (With Transit Lanes)

3.5m 3.5m
Shoulder Shoulder

1 on 'X'
1 on 'X'

Type 28 Channel
Median Slope 'X' varies
1 on 10(min) - 1 on 3(max)

7-79
Chapter 7: Cross Section

Eight Lane Divided Motorway with Transit Lanes - 15.0m Median

7
 Chapter 7: Cross Section Road Planning and Design Manual

References PIARC, 1999: “The Quality of Road Service -

Evaluation, Perception and Response Behaviour
American Association of State Highway and of Road Users”.
Transportation Officials (AASHTO), 2002:
“Roadside Design Guide”. PPK Environment & Infrastructure Pty Ltd, 2000:
Brisbane HOV Arterial Roads Study Final Report
Australian Road Research Board (ARRB), 1983: - Queensland Department of Main Roads,
“Guidelines for Rural Road Improvements - a Queensland Transport and Brisbane City Council.
Simulation Study” ARRB IR AIR 359-10.
Queensland Department of Main Roads, 1975:

7 Austroads, 1987: “Standards and Guidelines for

the Construction of National Highways”.
“Urban Road Design, Volume 1”.

Queensland Department of Main Roads, 1998:

Austroads, 1993: “Guide to Geometric Design of “Road Landscape Manual”.
Rural Roads”.
Queensland Department of Main Roads, 2000a:
Austroads, 1995a: “Guide to Traffic Engineering “Fauna Sensitive Road Design, Volume 1: Past
Practice”, Part 13 - Pedestrians. and Existing Practices”.

Austroads, 1995b: “Guide to Traffic Engineering Queensland Department of Main Roads, 2000b:
Practice”, Part 11 - Parking. “Road Traffic Noise Management: Code of
Practice”.
Austroads, 1999: “Guide to Traffic Engineering
Practice”, Part 14 - Bicycles. Queensland Department of Main Roads, 2001:
“Road Drainage Design Manual”.
Department of Main Roads QLD, 1997: “Manual
of Uniform Traffic Control Devices - Guide to Queensland Department of Main Roads, “Road
Pavement Markings”. Design Manual, Volume 1”.

Department of Transport and Communications, Roads and Traffic Authority (NSW): “Road
Federal Office of Road Safety, 1991: “Australian Design Guide”.
Code for the Transport of Explosives by Road and
Rail (Australian Explosives Code)”. Standards Australia, 1990a: “AS1742.6 - Manual
of Uniform Traffic Control Devices - Service and
Department of Transport and Communications, Tourist Signs for Motorists”.
Federal Office of Road Safety, 1992: “Australian
Dangerous Goods Code”. Standards Australia, 1990b: “AS1742.8 - Manual
of Uniform Traffic Control Devices - Freeways”.
NAASRA, 1986: “Guide to the Design of Road
Surface Drainage”. Standards Australia, 1992: “AS1743 - Road Signs
- Specifications”.
NAASRA, 1979: “Guide to the Provision and
Signposting of Tourist Facilities”. Standards Australia, 1993: “AS1742.7 - Manual
of Uniform Traffic Control Devices - Railway
NSW Department of Land and Water Crossings”.
Conservation, Soil Conservation Service, 1998:
“Construction Site Erosion and Sediment Control Transportation Research Board, Washington DC
- Course Notes - Level 2”. (TRB), 1994: “Highway Capacity Manual”
Special Report 209.
NSW Department of Land and Water
Conservation, 1996: “Urban Erosion and Wilden, L.A., 1997: High Occupancy Vehicle
Sediment Control - Field Guide”. Facilities Policy and Implementation
Considerations - Queensland Main Roads South
East Region Symposium.

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Road Planning and Design Manual Chapter 7: Cross Section

Relationship to Other • Intersection elements have dimensions

Chapters dependent on cross section requirements
(Chapters 13 and 14);
• Chapter 1 deals with the strategic requirements
• Widths of auxiliary lanes affect the cross
of the road system and will have a significant
section (Chapter 15);
influence on the type of cross section adopted;
• Interchange elements have dimensions
• Chapter 2 describes the planning of roads – the
dependent on cross section requirements
appropriate cross sections for these roads will
(Chapter 16);

7
have a significant effect on the planning
outcomes; • Providing for lighting affects the cross section
(Chapter 17);
• Chapter 3 sets out environmental requirements
– these are crucial in the design of cross • Traffic signals require space in the cross section
sections; (Chapter 18);

• Chapter 4 describes the standards to be applied • Providing for ITS is an integral part of the cross
to roads of different types; section (Chapter 19);

• Chapter 5 describes the particular requirements • Cross section elements have to be applied to the
of various road users – design of roadside amenities (Chapter 20);

- Pedestrians; • The road cross section has to be compatible

with railway level crossings (Chapter 21); and
- Cyclists;
• Bridges, retaining walls and tunnels have to be
- Road users with a disability; and
designed to the requirements of the cross
- Motorcyclists; plus section required to serve the traffic carried
(Chapter 22).
• Chapter 5 defines the dimensions of the various
design vehicles; This shows that there is no aspect of road design
that is not affected by the cross section
• Operating speed can be affected by the cross requirements. There is an interrelationship
section (Chapter 6); between the cross section elements and the other
design considerations and all design involves
• Chapter 8 is closely related to this chapter and some level of iteration between these
they must be read in conjunction with each considerations and the cross section.
other;

• Sight distance on horizontal curves will affect

the cross section (Chapter 9);

• The appearance of a road is affected by the

detail of the cross section (Chapter 10);

• Curve widening will affect the cross section

(Chapter 11);

• Width of pavement is affected by the radius of

crest vertical curves where manoeuvre sight
distance is the best available (Chapter 12);

September 2004 7-81

 Chapter 7: Cross Section Road Planning and Design Manual

Appendix 7A: Template for Vehicle Clearance at Property

Entrances

Front Rear
Overhang Wheelbase 3380 Overhang
1070 1600

Front Centre Rear

Clearance Clearance Clearance
Normal 280 100 270

Front dive (braking) 180 65 300

Rear jounce 300 65 160

Full jounce 200 25 190

Clearance dimensions under various conditions for composite longest vehicle

Front Rear
O.H Wheelbase 2030 O.H
560 815

Front Centre Rear

Clearance Clearance Clearance

Normal 150 125 115

Front dive (braking) 85 100 135

Rear jounce 160 100 45

Full jounce 100 75 65

Clearance dimensions under various conditions for composite shortest vehicle

* Use normal load as a basis for design of entrances, but the effects of greater spring
deflections should be checked.
* The dimensions shown relate to those of a composite design vehicle and do not
necessarily apply to the particular models shown.

7-82 September 2004

Road Planning and Design Manual Chapter 7: Cross Section

Appendix 7B: The route should be further evaluated if the

Multi-Combination Vehicles minimum carriageway width in the urban area is
less than the applicable width shown in Table B1.
in Urban Areas
Through lanes provide travel without obstruction
There are a number of clearance requirements to due to parked vehicles or stationary turning
be considered for MCVs travelling in urban areas. queues and therefore minimise the necessity for
The carriageway widths should take into account lane changing manoeuvres. It is preferable that at
various existing features including parking least two continuous through lanes are available
demand, angle of parking and the demand for on-

7
in the direction of travel. Short sections of single
road cycling provisions. through lane may be permitted.

Table B1 Minimum Carriageway Clearance Widths in Urban Areas

B-Double Type 1 Type 2

Feature Road Train Road Train
60-70 80-100 60-70 80-100 60-70 80-100
km/h* km/h* km/h* km/h* km/h* km/h*
(Undivided carriageway - 2-way) Width 3.8 4.2 4.0 4.4 4.2 4.8
between road edge and road centre
• with marked separation line 4.1 4.8 4.3 5.0 4.5 5.4
• with in-road cyclists 5.3 6.3 5.5 6.5 5.7 6.9
• with regular parallel parking 6.0 6.4 6.2 6.6 6.4 7.0
• with regular angle (45°) parking 9.8 9.9 10.0 10.1 10.2 10.5
(Divided carriageway - single lane) 4.1 4.8 4.3 5.0 4.5 5.4
Width between road edge and edge
of median/traffic island
• with in-road cyclists 5.3 6.3 5.5 6.5 5.7 6.9
• with regular parallel parking 6.3 6.4 6.5 6.6 6.7 7.0
• with regular angle (45°) parking 9.8 9.9 10.0 10.1 10.2 10.5
(Divided carriageway - 2 lanes) 7.2 8.3 7.4 8.5 7.6 8.9
Width between road edge and edge
of median/traffic island
• with in-road cyclists 8.4 8.8 8.6 10.0 8.8 10.4
• with regular parallel parking 9.4 9.9 9.6 10.1 9.8 10.5
(Divided carriageway - 3 lanes) 10.1 10.7 10.5 11.1 10.9 11.9
Width between road edge and edge
of median/traffic island
• with in-road cyclists 11.3 12.2 11.7 12.6 12.1 13.4

* Legal Speed Limit for the particular section of road being assessed.
(Source: Assessing the suitability of routes for Multi-Combination Vehicles Guidelines, WA, 22 March 2000, p.6)

September 2004 7-83