Water Supply & Distribution – CEIE 440/540

Spring 2010 – Version 5

(20 January 2010)

Preliminary Design Report Project

The team will prepare a Preliminary Engineering Report (PER) for the design of a public water system for
a community in the Commonwealth of Virginia. The PER will include recommendations for the
community’s source water, water treatment plant, and distribution system. You will make a formal oral
presentation of your PER to the class and invited guests on April 28, 2010 to receive their questions and
critiques. Your PER will be due at the start of class on May 05, 2010. You will provide progress reports of
your work on February 10, 2010 and on February 24, 2010. While some information will be provided to
the team from time to time, most of the information needed to complete the PER requires research by the
team. The PER must carefully document and justify all research, assumptions and decisions of the team so
that your references can be found and reviewed by those reading your report.

Objective of the Preliminary Engineer Report (PER)

The objective of your PER is to:

• Work on behalf of your client (the community council) to provide them with the best professional
information and recommendations that you can develop to permit them to make an informed
decision.

• Analyze the public water system that the community needs to meet its demands.

• Identify a sustainable source water supply to meet the community public water needs into the
future.

• Analyze and design source water systems for the community

• Analyze and design the community’s water treatment plant

• Analyze and design a key portion of the community’s distribution system

• Determining the cost of the needed projects

• Analyze the affordability of the project to the community

• Calculate the rates, fees and charges that the governing body of the community will have to charge

• Support the community leadership to keep its citizens informed throughout the process
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Community Information
(a) A Virginia community had a population of 8,592 people on the 2000 federal census. Today its
population is (15% of the average of your team’s GMU student ID numbers rounded to the nearest
whole number).

(b) The community is located 1.5 miles from a river and may also have a number of wells capable of
providing its public water supply.

(c) The community has been purchasing water from a neighboring town, but now believes that it
needs to own and operate its own public water system. It can purchase land at an elevation of
55-feet (msl) for $76,000/Ac to build a water treatment plant in the community.

(d) The community has planned for all new commercial and industrial growth to be located in
Section: (the average of your team’s [GMU student ID numbers divided by 3992] the result minus
“1”, rounded to the nearest whole number) and Quadrant: (your team leader’s GMU student ID
numbers divided by 161,103, rounded to the nearest whole number).

(e) The current water rates are $2.65/1,000 gallons.

(f) The community hopes to pay for the new system by floating 5.10%, 30-year bonds.

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Demand Analysis
Objective
To determine the quantity of public water (demand) that the community needs.1

Background
The community water demands (residential, commercial & industrial) need to be determined. For your
initial planning, anticipate that a new water system will cost about $7,000/1,000 gal2 of system capacity to
build, that it will take 2-years to plan and design, 1-year to obtain the necessary permits and 3-years to
construct. By convention, bond payments do not begin until the plant goes into production. Table 1
provides information developed by the community’s planning office.

Table 1 – Confirmed Facilities & Water Demands3

Facility Notes
Residential Demands
The community today is essentially 100% residential with commercial and industrial growth in the future.
The team will need to decide how to project the residential growth from today until the end of the planning
period.
Commercial Demands
Low-Income A temporary complex with a demand of 70,000 gal/day will open in 2010 but will close
Apartment over the next 15 year. The plan is to have 1/3 of the apartments empty at the end of every
Complex 5-years.
Shopping A 68,000 ft2 floor space shopping center is planned to be in business from 2021 until it
Center closes in 2035
Cineplex A 10-theater Cineplex, each theater seating 250 people is planned for 2018 through 2027
Three major new restaurants for the area, beginning in 2013 include an 85-seat Mexican
Restaurant Restaurant, 122-seat French restaurant, and a 62-seat McDonalds. The community only
Complex gave McDonalds an 8-year operating permit, as they really don’t want it in the new town
center. These restaurants will move out of the area by 2034.
Hospital 1000-bed, general care hospital will begin operations in 2019
A new High School with a maximum capacity of 1,100-students, is expected to start in
2017 with 845-students and grow over the next 4-years before it reaches its capacity.
High School
School enrollment is projected to drop starting in 2026 by 350-students when a new
school (outside of the area) will open and draw students.
A branch of the university plans to open a campus in the community in 2013. It will
Community
ultimately have 35,000 students. The University will open with 3,000 students. They
University
expect to add 1,200 students/year thereafter.

1
For planning, assume that the infrastructure will reach capacity in 30-years at which time a new planning increment
will be required.
2
This is only your first guess for planning purposes. You will need to refine this number as your design progresses.
3
Virginia Waterworks Regulations, 12VAC5-590-690 found at http://leg1.state.va.us/000/reg/toc12005.htm, you may
find Code: Chapter 590, Section 690, Para. A useful in determining demands.

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Industrial
A new plastics fabricator plans on operating with 2-8 hr shifts M-F and 1-8 hr shift on Sat.
Plastics
They require 27,600 gallons/shift. They are closed on Sunday. The factory wants to be in
Fabricator
operation from 2013 through 2027.
The plant currently uses 78,000 gallons/day and forecasts growth of 2%/year. They hire a
Pepsi Bottling lot of community residents (votes?) and pay a lot of taxes. The community leaders really
Plant like this “cash cow” but the plant manager has indicated that they will leave if their cost of
water exceeds $4.00 / 1,000 gallons.
A new shipyard will go into business in 2020 with one dry-dock. They anticipate
averaging 5 ships/year to start. The average stay of each ship is 18 days. The yard
Dry Dock
expects its business to grow by 2 ships/year. Their water demand is 860 gal/hr when a
ship is in dry dock, but drops to 12,500 gal/day when no ship is being serviced.
Distribution System
The current distribution system is almost 55 years old system with unaccounted water estimated to be at
least 15.6%.

Approach

(a) Build a spreadsheet model to analyze the demands. Set up columns for:
i. End of Year of Planning Period
ii. Residential Demands
iii. Commercial Demands (recommend providing a column for each new commercial demand)
iv. Industrial Demands (recommend providing a column for each new industrial demand)
v. Total Average Day Demands  basis for billing
vi. Tot Avg Day + Unaccounted
vii. Tot Avg Day + Unaccounted + PF  Sum of all new demands
viii. New Commodity Charge ($/1000 gal)

(b) Set up target cells for:

i. Unaccounted Water
ii. Peaking Factor
iii. Construction Unit Cost ($/gal capacity)
iv. Bond Interest Rate (%)
v. Bond Term (yrs)

1. Determine the current water demand, future water demand and the maximum capacity of the public
water system that is required.

2. Calculate the capital cost of the required public water system.

3. Calculate the monthly debt service on the bonds.4

4. Develop a plot of the water sales in the community and discuss what it implies.

5. Calculate the commodity charge (customer’s billing rate in $/1,000 gallons).5

6. Were you able to save the bottling plant? If not, discuss how you handled this loss.

4
Although you sell construction bonds and get your money before construction starts, bond payments do not
typically start until the plant goes into production.
5
These are the absolute minimum additional rates that you will have to charge your customers just to meet the new
debt service. In practice, utilities average these projected rates when setting commodity charges.

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Supply – Ground Water Analysis

(27 January 2010)

Objective
To investigate the use of ground water to support the community.

Background
Ground water is a possible source of water for your community. The geologist report indicates that a 100-
foot thick, permeable basalt aquifer starts 180-feet below the surface. To determine the safe yield of the
new well, the driller ran a yield step-test with results as shown in Table 2. The driller also ran a drawdown
test at the new well’s maximum steady-state flow rate. The drawdown at the well’s maximum sustained
yield was measured in an observation well located 30-feet away, with results as shown in Table 3.

Table 2 Table 3
Well Step-Test Results Well Drawdown Test at Maximum Sustainable Yield
Time after Time after
Steady-state
Pumping Rate start of Drawdown start of Drawdown
Drawdown
(Q-gpm) pumping (Δh-ft) pumping (Δh-ft)
(ft)
(min.) (min.)
0 0 1 4.5 60 23.4
300 2.1 2 7.4 80 25.0
600 8.3 3 9.1 100 26.7
900 18.2 4 10.4 200 29.6
1,200 28.9 6 12.1 400 32.5
1,500 38.1 8 13.2 600 34.1
>1,500 fails 10 14.5 800 35.0
30 20.2 1000 36.0
40 21.7 1440 38.1
50 23.0

Approach

1. Ground Water Flow & Well Yield – Based on the geologist report and the generalized soil
characteristics table, estimate the permeability (K-gpd/ft2) of this aquifer. Calculate the aquifer’s
characteristics (T, K, & S), using the drawdown data from the well driller. Compare the estimated
aquifer permeability (K) to the calculated permeability and discuss the impact on the project had the
field-testing and calculations not been conducted.

(a)Plot the drawdown data (Δh vs. log t) [note: Δh is negative, plot below x-axis]
(b) Fit a trend line to the data
(c) Calculate time (t0)
(d) Calculate drawdown (∆h) over 1-log of time
(e) Calculate T (gpd/ft)
(f) Knowing the thickness (b) of the aquifer and its transmissibility (T), calculate its actual
permeability (K-gpd/ft2)
6
(g) Using the coefficient of storage equation, calculate S (gal/ft3).

2. Well Interference – Calculate the “additional” drawdown that this new well will impose on the well of
an existing subdivision well located 900-feet away. The existing well uses a submersible pump set
210-feet below the surface with 10-feet of water over its intake screen when the well is producing at its
maximum drawdown. Discuss the acceptability of this newly imposed drawdown on the existing well.

6
Remember to convert t0 to days

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What does Virginia groundwater law say about this new impact on the existing community’s water
supply? How does the aquifer’s storage capacity (S) impact this drawdown?

(h) Calculate u, the well function7 W(u) and the drawdown in the other well caused by this new well.

3. Water Works Regulations – Based on the Commonwealth of Virginia Water Works Regulations8
determine the maximum number of single-family houses (connections) which this well can support.
Calculate the amount of on-site storage required for this well. Determine the number and size of wells
required to serve your community if groundwater is used as the water source for the public water
system.

7
Interpolate do not estimate from well function table (Viessman, Table 3.5, p.45)
8
Virginia Waterworks Regulations, 12VAC5-590-690 found at Code, Chapter 590, Section 690, Para. A

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Supply – Surface Water Analysis

(3 February 2010)
Objective
To construct and use a spreadsheet model to identify and analyze the capability of the river to meet the
community’s requirements and the potential size of a reservoir that may be needed to assure a sustainable
water source.

Background
Flow records for a nearby river are available for the past 100-years. The record for the river’s period of
lowest flow ever recorded during this 100-year period is shown in Table 5. Evapotranspiration averages
1.6% of the summer river flow and 0.8% of winter river flow. The river transports an average of
4.5 AF/month 9 of sediment. If the river is dammed to form a storage reservoir, the state will require a
minimum flow down-stream of the dam of not less than 80 MGD at all times. The state also requires that
the new reservoir be multi-purpose, providing (a) water supply storage, (b) a flood control volume of
10.5 BG which must always be kept empty, and (c) a recreation pool for swimming and boating. The dam
and reservoir must have a 100-year life. It will cost $600,000/BG of dam volume to construct a dam and
reservoir.

Approach to Evaluate the River

To approach your analysis of using the river as a water source for the community, you will want to build a
spreadsheet model of the river’s period of lowest flows with the following columns:

(a) Rank
(b) Date
(c) Average Monthly Flow (MGD)
(d) Probability of Exceedance-P (%)
(e) Return Period-T (Mo)

Sort the dates & flows in descending order (largest to lowest flow).
Rank each flow with “1” assigned to the greatest monthly flow.
Calculate the Probability of Exceedance (P) and the Return Period (T) for each flow.

1. What is the probability that this river will be able to meet the greatest water demands of the community
should there be a return of the drought of record?10

2. Discuss your comfort with using the river as a water source for the community. What do you
recommend to make this river an acceptable water source for its public water supply?

Approach to Evaluate a Required Reservoir

Build a spreadsheet model to determine the maximum water supply deficiency (MG) that the community
would face should the river’s worst flow of record return with columns labeled as follows:

(a) Date
(b) Days/mo.
(c) Average Monthly Flow (MGD)
(d) Average community Daily Demand (MGD)11

9
AF/mo – Acre-foot per month. 1 Acre = 43,560 ft2
10
You will have to interpolate from the data in your model
11
Here is a trick you may want to try to save time and mistakes. Set-up a “target field” for this value. When you
need this value in your model, just refer to the target cell. You can quickly change the target value and it will
change every place in your model that it is used. It is a great way to test different scenarios. I recommend targets
for winter demand, summer peaking factor, flow-by, summer ET, winter ET, construction nit cost, bond interest
rate, loan period.

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(e) Evapotranspiration Demand (MGD)

(f) Add’l release to meet minimum in-stream flow req. (MGD)12
(g) Total average daily demand (MGD)
(h) Monthly Inflow (MG)
(i) Monthly Outflows (MG)
(j) Cumulative Inflow (MG)
(k) Cumulative Outflow (MG)
(l) Deficit (MG)

3. Graph 13 the cumulative inflows and cumulative outflows over the period. Discuss the significance of
the maximum distance between these two flows during both periods of reservoir fill and draw.

4. What is the minimum volume reservoir (BG) needed (the greatest water deficit) to provide the
community with a dependable water supply?

5. What volume will you need to accommodate the anticipated sediment deposits over the life of the
reservoir?

6. Discuss the additional volume that is needed to support the recreational uses of this new reservoir?

7. What is the total volume of the proposed new reservoir? Prepare a pie chart showing the proportion of
reservoir volume allocated for each function.

8. Graph a comparison between the average monthly river flow to the average monthly community demand
during the period of lowest river flow. Discuss what the volume between the two lines implies about the
reservoir operations.

9. Calculate the total cost to construct the new dam and reservoir and the cost to construct just the water
supply pool?

10. Calculate the monthly payment that the community will have to make to repay their construction
bond.14

11. What is the water rate ($/1,000 gallons of water15) that the utility’s customers will have to pay to cover
the cost of this new reservoir?

12. A group of environmentalists claims that the required minimum in-stream flow is too little to sustain
the health of the river’s aquatic life. They want a minimum river flow no less than 100 mgd. Using your
model, analyze the impact on the size and construction cost of the water supply pool, and on the change in
water rates that would be required to meet this demand. Finally, comment on your impression on the merit
of this demand.16

13. The mayor tells you that politically he cannot support a water rate for a new reservoir of more than
$0.25/1,000 gallons. Use your model to analyze what you might do to meet the Mayor’s cost ceiling and
then discuss what you will finally recommend to the Mayor.

12
You release additional water from the reservoir to the river only if the river flow is less than the minimum required
in-stream flow rate and then only as much as is needed to get the river back up to the minimum in-stream flow rate.
13
At a minimum, a technical graph must have a (a) title, (b) Axis labels and (c) legend if there is more than one
variable on the graph.
14
You are looking for the monthly payment (PMT function) so be careful, you will need to convert your interest rate
from an annual to a monthly rate and the number of periods from annual to monthly.
15
It is common for water utilities to state their rates per 1,000 gallons of water that the customer uses.
16
Examine the natural river flows during the drought of record and compare this to the in-stream flows that the state
requires and also the flows that the environmentalists request.

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Table 5 – River’s Historic Lowest Flow of Record

(30-year period of record)

Average Monthly Average Monthly Average Monthly

Month Minimum Flow of Month Minimum Flow of Month Minimum Flow of
Record (MGD) Record (MGD) Record (MGD)
Jan-27 146.4 Dec-27 5.2 Nov-28 128.0
Feb-27 74.1 Jan-28 4.8 Dec-28 96.0
Mar-27 86.4 Feb-28 54.4 Jan-29 65.9
Apr-27 100.8 Mar-28 118.4 Feb-29 71.2
May-27 115.2 Apr-28 158.4 Mar-29 137.6
Jun-27 35.6 May-28 132.5 Apr-29 102.4
Jul-27 33.0 Jun-28 115.2 May-29 171.5
Aug-27 20.2 Jul-28 113.9 Jun-29 204.8
Sep-27 12.8 Aug-28 131.2 Jul-29 140.8
Oct-27 11.5 Sep-28 102.4 Aug-29 102.4
Nov-27 3.8 Oct-28 137.6

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Water Treatment Plant Design

(10 & 17 February 2010)

Objective: To size a conventional water treatment plant with rectangular sedimentation basins, rapid
rate filters and free-chlorine disinfection, and define the geometry of its major unit
processes.

Approach: Your work is to be based on the Commonwealth of Virginia Waterworks Regulations.

The regulation section that you use and the assumptions that you make must be clearly
documented in your report. This is a design project therefore there is no single correct
result, but a good engineer always strives for the most cost-effective way to meet the
client’s needs. Land, steel, concrete and electricity are expensive therefore you will want
to design the smallest plant that can safely serve the community. Your report to the
community must discuss the following (supported by your calculations):

Timeline

1) Prepare a Gant Chart to demonstrate to the town council the activities from the 2000
census leading up to placing a new plant in service and then the service-life of the
plant. Show lapse time since census, design time, permitting time, construction time,
and operating period.17

Intake

2) The capacity of the river intake structure.

3) The size of the force main from the Raw Water Pump Station (Low Service) to the
plant. (Keep pipe velocities >1.5 ft/sec to prevent settling of solids within the
pipeline and < 8 ft/sec to limit head loss).

Flash (Rapid) Mixing

4) The dimensions and detention time of the flash mix basin(s). (Code: Chapter 590,
Section 870, para C2)

5) The power input required for this flash mixer. (Code: Chapter 590, Section 870, para
C3b)

Flocculation18

6) The number of flocculation basins and the number of stages/basin. (Code: Chapter
590, Section 870, para D2d)

7) The required detention time and the dimensions of the flocculation basins. (Code:
Chapter 590, Section 870, para D2a)

8) The power required to be imparted by the flocculators in each basin assuming a

Power Gradient of G=45/sec. (Code: Chapter 590, Section 870, para D2b)

17
There are a lot of Gant Builders available. You may want to look at the PowerPoint add-in by Roman Koch in the
reference material on the course site.
18
Since you want to match the geometry of your flocculation basin to the sedimentation basin, it is probably better to
design the sedimentation basin first and then return to design the flocculation basin.

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Sedimentation

9) The number of sedimentation basins & flow rate per basin.

10) The surface overflow rate (SOR) and reason for its selection. (Code: Chapter 590,
Section 870, para E4).

11) The minimum surface area of each sedimentation basin based on the SOR.

12) The basin detention time and reason for its selection? (Code: Chapter 590, Section
870, para E1)

13) The volume of each basin based on the detention time. (Code: Chapter 590, Section
870, para E4)

14) The width of each basin.

15) The length of each basin based on the width and area.

16) The velocity through the sedimentation basins for compliance with the waterworks
regulations (Code: Chapter 590, Section 870, para E3).

17) The depth of each basin based on the flow rate, maximum velocity and width.

18) Check for velocity compliance.

19) Check for L:W compliance.

20) Check for L:d compliance

21) Check for Laminar flow (Re).

22) Check for Principal direction of flow (Fr).

Filtration

23) The number of filters and the number of filter boxes. (Code: Chapter 590, Section
880, para A2)

24) The magnitude and justification for the filter surface loading rate. (Code: Chapter
590, Section 880, para A3)

25) The dimensions of each filter to achieve a L:W = 2 to 3. The dimensions of each
filter box including the drain gullet. (Code: Chapter 590, Section 880, para A4e)

26) The total volume of water needed to backwash one filter box if the filters are to have
an effective life of 36-hours with efficiency not less than 95%.

Disinfection

27) The type and justification for the clearwell baffling. (Code: Appendix Table L-8)

28) The CT10 required by your system to provide a finished water with a chlorine
concentration of 2.0 mg/l, if you assume that the finished water has a pH=7.5. (Code:
Appendix Table L-1)

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29) The clearwell detention time.

30) The volume and dimensions of the clearwell?

Land Requirements and Layout

19
31) Itemize the land needed for the unit processes . Assume an additional 20% to
accommodate solids handling processes, 50% for ancillary buildings plus land for an
20
appropriate buffer around the plant.

32) Prepare a well0-desinged & annotated autoCAD plan view of the plant layout
including:

(a) Unit processes and interconnecting piping (water train)

(b) Unit processes and interconnecting piping (solids train)21
(c) Supporting buildings needed to sustain plant operations
(d) Security requirements (e.g., fences/gates, guard points, set-back & clear zones)
(e) Roads

Finances

33) Determine the cost of this plant. The cost for land where you will build the plant is
$76,000/Ac. The capital cost of construction is anticipated to be $2.87/gal of plant
capacity.

34) The monthly debt service for this new plant.

35) The monthly “commodity charge” ($/1,000 gal) you will recommend billing your
customers in the first month and in the last month that the new plant is in operation
to service this debt.

19
You need to provide space between processes for maintenance, walkways, roads, etc.
20
You might consider compiling this information as a table that you include on your drawing.
21
Unit process of the solids train do not need to be designed for this project, but their “general” size and location need
to be included in your plan.

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Distribution System Design

(3 Mar 2010 – 21 Apr 2010)

Background

Design a transmission and distribution system from the wet well at your water treatment plant to the section
(see community notes) that the community has selected for the new facilities. Ask your client for site maps
of this area.

Approach:

Design

a) Demands – You will use the demands already developed for the community (see Appendix A for the
demand patterns). You must meet 5% of the residential demands forecast, all of the commercial
demands and all of the industrial potable water demands.

b) Tank – Design an elevated storage tank in your section to float on the pressure zone for equalization
plus 1.0 MG of emergency storage. Tank capital cost is $1.25/gallon of tank storage.

c) Pump Station – Design a pump station at the entrance of the development to provide satisfactory
operating pressures within the section. Pump station capital cost is $12,500/ft of required peak pump
head (TDH). Be sure to check for pump cavitation across its entire operating range – including fire
flows.

d) Surge Pressure – (a) Maximum surge pressures anticipated for the mains should a valve suddenly be
slammed shut at the suction to the pump during fire flows and (b) the minimum valve operating time to
prevent damage.

e) Thrust Block – The dimensions (bearing area) of the thrust block required to restrain a 135-degree
horizontal bend. The soil in this area has a bearing pressure of 8,000 lb/ft2.

f) Pipe Class – Specify the pipe type, thickness and class to use.

g) Laying conditions – Specify the laying conditions to be used by the contractor

h) Water Quality – The result of water quality testing at your section showed an average water age of
20 hours and a bulk water decay coefficient kB = -2.0 mg/l/day. Water over 60-hours old may have
taste and odor problems while water over 96-hours old must be checked for formation of disinfection
by-products. Use a wall decay coefficient of kw = -0.2 ft/day.

i) Fire hydrants – The fire code requires a hydrant within 500-feet of a single family residents and
250-feet of commercial facilities with a residential NFF of 1,000 gpm and a commercial NFF of 3,125
gpm.

Layout – Your distribution system drawings should be detailed with at least the following:

a) Alignment (horizontal only)

b) Size (pipe diameter and pipe class)
c) Minimum and maximum water main cover
d) Pump Station size & location
e) Storage Tank size & location
f) Valves (isolation)
g) Hydrants – location & a typical “Standard Hydrant Installation” detail.

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h) Easement requirements
i) ROW requirements
j) Corrosion protection

Cost Estimate

a) Operating Cost – Calculate the monthly power requirement & cost of operating the new pump station
if effp = 89%, effm = 95% and electric cost = $0.04/Kw-Hr.

b) Capital Cost – Provide the “engineers opinion of probable cost” of construction.

Discussion

a) Water Quality – Discuss any water quality (age) issues you anticipate with your design, where they
will occur and what could be done to improve the water quality.

b) Chlorine Residual – Evaluate the chlorine residual at each demand center and discuss its acceptability
(Minimum 1.0 mg/l concentration required)

c) Pump Station – Evaluate how closely the pump operates to its BEP over the period of a day and
discuss the ramifications of your findings.

d) Public Acceptance – Discuss the anticipated public reaction to this project and discuss your strategy to
address the issues.

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References

a) Virginia Water Works Regulations ........................................http://leg1.state.va.us/000/reg/toc12005.htm

b) FCWA Design Practice Manual ...................................................................................................... pp. 6 - 18

(www.fairfaxwater.org/engineering/DevDesignReview/DESIGN-PRACT3-00update.pdf)

c) Fairfax Water Standard Details

(http://www.fairfaxwater.org/engineering/Standard_Details/FW%20DETAILS%20JAN09.pdf)

d) Ductile Iron Pipe Design...................................................................AWWA C-150 DIP Design Standards

e) Water System components .......................................................................................www.usabluebook.com

f) Demand Patterns...........................................................................................................................Appendix A

g) FCWA Pipeline Cost Guide......................................................................................................... Appendix B

h) Pressure Transient Nomagraph.................................................................................................... Appendix C

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Appendices

Appendix A

FW Demand Patterns
(Shown are the times when the pattern changes)

Time
Residential Commercial Industrial
(24-hr clock)
0 0.3 0.0 0.2
1
2
3
4
5 1.5
6 1.8
7
8 1.0
9 2.5
10 0.5 1.8
11
12 1.2 2.0
13
14 1.0
15
16 1.8
17 1.8
18 0.0
19 1.5
20
21 1.0 0.2
22
23
24 0.3

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Spring 2010 Design Project (v5)
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Appendix B
22
Pipeline Cost Guide

Cost per foot in developed areas (includes valves, fittings and restoration)
Size <100-feet 100 – 500 feet >500 feet
3”
4” $215 $180 $175
6” $220 $180 $180
8” $235 $195 $190
10” $252 $207 $202
12” $270 $220 $215
14” $302 $232 $225
16” $335 $245 $235
20” $385 $265 $255
24” $430 $300 $290
30” $520 $375 $370
Casing Pipe (does not include water main within casing pipe)
6” w/m - 16” $295
8” w/m - 20” $375
10”–12” w/m - 24” $450
14”– 16” w/m – 30” $540
18”–20” w/m – 36” $655
Fire Hydrants
Standard Hydrant $4,540
Wet Tap Hydrant $9,190
Note: When estimating the cost of projects under $100,000 add 10% for
contingencies and 15% for engineering, administration and overhead
(min. $5,000). For projects over $100,000, use 5% and 10%.

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Based on Fairfax County Water Authority installed pipe prices (9/15/08)

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Spring 2010 Design Project (v5)
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Appendix C
Pressure Transient Nomagraph

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