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Report Taskforce

The South Fork Rivanna Reservoir Stewardship Task Force was appointed to identify the benefits provided by the South Fork Rivanna Reservoir to the community and recommend measures to maintain those benefits. The Task Force was specifically instructed not to revisit the community's long-term water supply plan. In their report, the Task Force addresses their mandate by describing the Reservoir's history, identifying its current benefits to the community, recommending effective maintenance measures, discussing the Reservoir's future without action, and outlining next steps.

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0% found this document useful (0 votes)
135 views23 pages

Report Taskforce

The South Fork Rivanna Reservoir Stewardship Task Force was appointed to identify the benefits provided by the South Fork Rivanna Reservoir to the community and recommend measures to maintain those benefits. The Task Force was specifically instructed not to revisit the community's long-term water supply plan. In their report, the Task Force addresses their mandate by describing the Reservoir's history, identifying its current benefits to the community, recommending effective maintenance measures, discussing the Reservoir's future without action, and outlining next steps.

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readthehook
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© Attribution Non-Commercial (BY-NC)
We take content rights seriously. If you suspect this is your content, claim it here.
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You are on page 1/ 23

South Fork Rivanna Reservoir

Stewardship Task Force Report

Members:

Holly Edwards—Charlottesville City Council January 26, 2009


Mark Fletcher—University of Virginia
Mike Gaffney—Rivanna Water and Sewer Authority
Tom Jones—Reservoir Property Owners
Karen Joyner—Ivy Creek Foundation
Chris Lee—Chamber of Commerce
John Martin—Rivanna River Basin Commission
Wren Olivier—Sierra Club
Liz Palmer—Albemarle County Service Authority
Dennis Rooker—Albemarle County Board of Supervisors
Ridge Schuyler—The Nature Conservancy
Dede Smith—Citizens for Sustainable Water Supply
Sally Thomas—League of Women Voters, Chair
Report of the South Fork Rivanna Reservoir Stewardship Task Force

The South Fork Rivanna Stewardship Task Force was appointed to articulate the benefits the
South Fork Rivanna Reservoir (the “Reservoir”) affords our community and to describe the
measures that would need to be undertaken to maintain those benefits. This report presents the
results of that work.

To understand the approach of the task force, it is important to understand the context in
which it was created. For years—if not decades—the community has wrestled with how best to
increase the amount of drinking water it can store to see it through times of drought. In June
2006, the community chose to expand the existing Ragged Mountain Reservoir, rather than
increase the capacity of the South Fork Rivanna Reservoir, which is losing water storage
capacity due to sedimentation. Having made this decision, it raised the question about what
would become of the South Fork Rivanna Reservoir. While it has ably served the community as
its major water storage facility, that role will be served in the future by the expanded Ragged
Mountain reservoir, which does not fill with sediment. The task force was asked to describe the
other benefits, beyond water storage, that the South Fork Rivanna Reservoir provides to this
community. As a result of that charge to the task force, this report does not revisit the
community’s 50-year water supply plan. In fact, the task force was specifically instructed not to
do so, so we have not. With that background, the Task Force is pleased to present this Report to
its four appointing bodies for community consideration.

I. The Task Force Mandate

The Task Force was established by joint action of the Chairmen (or Mayor) of the City
Council of Charlottesville, Albemarle County Board of Supervisors, the Rivanna Water and
Sewer Authority (RWSA) and the Albemarle County Service Authority (ACSA). At its first
meeting on August 12, 2008, the Task Force was presented with an “outline of work.”1
Thereafter, on October 27, 2008, the Task Force received clarification of its assigned purpose, as
follows:

1
“Outline of Work for the South Fork Reservoir Stewardship Task Force,” prepared by the Mayor of the City of
Charlottesville, the Chairman of the Albemarle County Board of Supervisors and the Chairmen of the two water
Authorities. (Appendix A)

2
Joint Statement by
Charlottesville Mayor Dave Norris
and Albemarle County Board Chair Ken Boyd
Clarifying the Purpose of the South Fork Reservoir Stewardship Task Force
10/28/08

First, we want to thank the members of the South Fork Reservoir Stewardship Task Force, and the
members of the public who have been attending these meetings, for your contributions to this
important community discussion about the future of the South Fork Rivanna Reservoir.

We understand that there has been some confusion about the City's and County's expectations for
this Task Force, and we came here tonight to share our perspective on this matter and hopefully
bring more clarity and focus to your work. Note that this statement reflects our personal opinions
as members of the “Four Chairs” group that chartered this Task Force, and has not been endorsed
by either the City Council or the Board of Supervisors.

To understand the purpose of the South Fork Reservoir Stewardship Task Force, it's helpful to
refer back to the water supply resolution unanimously approved by the City Council on 6/2/08 and
by the County Board of Supervisors on 6/11/08, which included the following text:

“BE IT FURTHER RESOLVED that in addition to the specific elements of the local Water
Supply Plan endorsed and approved by this Resolution, the City Council [Board of Supervisors]
hereby requests the Rivanna Water and Sewer Authority to undertake a study of the South Fork
Rivanna Reservoir and the viability and merits of maintenance dredging, siltation prevention and
any other appropriate initiatives that could maintain and enhance the aquatic health and water
quality of the South Fork Rivanna Reservoir, as a valuable water resource for the long term future
benefit of the community.”

It's important to note that this Task Force was conceived in the context of a joint City-County
reaffirmation of the basic parameters of the proposed water supply plan. As is clear from the text
we just read, measures to sustain the long-term health of the South Fork Reservoir (potentially to
include dredging) were not envisioned as replacing, but rather supplementing, the other
components of the water supply plan approved by the City and County. In other words, this Task
Force was not charged with responsibility for reassessing the fundamentals of the water supply
plan itself. In our opinion, that is outside of your purview.

Having said that, it's also important to note that in our resolutions, the City and County both
acknowledged the valuable role that the South Fork Reservoir plays as a water resource for the
community—not just a place where people go to fish and row and play and enjoy nature. While
the Reservoir benefits our community in many ways, the Reservoir was created as a water supply
vehicle and will continue to serve in that capacity under any water supply scenario offered to date.
If this Task Force were to recommend that the Reservoir be dredged, to whatever extent and for
whatever purposes, it is clear that water supply gains would result. Whether or not you decide that
increasing the Reservoir's water storage capacity is one of the explicitly desired outcomes of a
maintenance regimen, keep in mind that there is no consensus as of today as to whether those
gains would be factored into the overall water supply equation and the water supply plan adjusted
accordingly (as Mayor Norris has suggested), or whether they would simply be seen as creating
additional supply to extend the life of the plan and/or give us greater capacity to manage any
future water emergencies. Again, that is a decision which lies outside the purview of this Task
Force.

In our opinion, the South Fork Reservoir Stewardship Task Force should focus its efforts on
building a well-rounded case as to how the Reservoir benefits our community, what measures
would be most effective in maintaining those benefits, what is likely to happen to the Reservoir if
no such measures are undertaken, and what the next steps would be in order to move those
measures forward. From there, as a result of your deliberations, we (the City, the County, the

3
Rivanna Water and Sewer Authority, and the Albemarle County Service Authority) can have a
much more well-informed discussion about how to proceed in implementing those next steps.

Outside the scope of this committee's charge, but on the broader issue of how to proceed with the
water supply plan itself, we both feel that the taxpayers and ratepayers of this community would
be well-served by a more thorough assessment of the costs and feasibility of the various
components of the adopted water supply plan, especially in light of the recent news about
escalating costs of the Ragged Mountain dam expansion project. We commend RWSA for taking
the proactive step of inviting in a panel of third-party experts to reassess the costs of replacing or
repairing the Ragged Mountain Dam. Whether by broadening the scope of that review process or
by proceeding with a parallel effort to engage independent experts in watershed and water supply
management, we believe RWSA should take advantage of this pause in the implementation
process to more closely analyze the key components of the adopted and alternative plans to ensure
that the path we choose for meeting our community water supply goals truly is the most
economically-and environmentally-responsible one. Finally, we would also remind our partners
and the public that both the City and the County have called for the initiation of stronger measures
to promote conservation and efficiency in our use of water, and that these too need to be
incorporated into the community's long-term water supply plan.

Thank you for giving us the floor, and thank you again for your interest in preserving and
2
enhancing this valuable community amenity.

Accordingly, this report documents the work of the Task Force, starting with a brief
description of how the work was undertaken (Section II). It presents relevant information
regarding the history of the Reservoir and its current state (Section III). The report then responds
to and addresses the four questions outlined in the Task Force mandate:

A. How does the SFRR benefit our community? (Section IV)

B. What measures (or actions) would be most effective in maintaining these benefits? (Section
V).

C. What is likely to happen to the Reservoir if no such measures are undertaken? (Section VI)

D. What are the next steps that Task Force recommends in order to move these measures
forward? (Section VII)?

II. Organization of Work

The Task Force met together as a group thirteen times, from our first meeting on August 12,
2008, through to our final meeting on January 26, 2009, to approve this Final Report. We used
the first meetings to collect information about the Reservoir and to help give Task Force
members a common understanding of the history of the Reservoir, its current conditions, and
how the Reservoir is being used (including and in addition to water supply and storage). To gain

2
The Resolutions of the City Council and Board of Supervisors, dated June 2, 2008, and June 11, 2008,
respectively, are set forth in the Appendix of this Report. (Appendix B, C)

4
this understanding, Task Force members developed a list of questions for RWSA staff, for which
answers were provided – and during early meetings heard presentations by staff of RWSA,
Albemarle County, Virginia Department of Game and Inland Fisheries, and
Charlottesville/Albemarle Airport. All minutes, presentations, answers to the above questions,
and a short list of facts about the Reservoir are on the Task Force web-pages at the RWSA web-
site (www.rivanna.org ). In addition, Task Force members were provided with information
through reports and personal communications, including the 2003 report, South Fork Rivanna
Reservoir And Watershed: Reflecting On 36 Years, Anticipating 50 Years, by Stephen Bowler,
formerly of RWSA and Albemarle County.

The Task Force also made site visits that included an on-the-water boat tour of the Reservoir
(hosted by UVA Rowing) and tours provided by RWSA of the South Fork Water Treatment
Plant and the Ivy Landfill (to see the ultimate deposition of solid material taken out of Reservoir
water in Water Treatment Plant). To more clearly understand many aspects of dredging, the
Task Force held a conference call meeting with Gahagan-Bryant, the dredging consulting firm
whose representatives came to Charlottesville in May 2008, and who said, "In order to scope a
dredging project, one must first define why one wants to dredge." Another dredging firm, the
Blue Ridge Sand Company, also made a presentation to the Task Force. Minutes of each
meeting and all presentations are included as appendices to this report. (Appendix D).

The Task Force heard from the public in a number of ways. The Task Force provided public
comment periods at several meetings and also provided an email address that gave the public an
easy way to address all Task Force members. To better understand how the public perceived the
benefits of the Reservoir, a special public hearing was held on October 27, 2008.

In addition, written and web-based questionnaires were used to obtain information regarding
public attitudes and expectations about the Reservoir. Three hundred seventeen respondents
shared their ideas with the Task Force through the questionnaire, and the Task Force learned
from and appreciated all the input. Respondents who expressed interest in dredging the
Reservoir said it would save money and provide water supply capacity, or they expressed the
feeling of ethical obligation to maintain this piece of infrastructure. The questionnaire was
displayed on the RWSA website (www.rivanna.org), and all responses can be found there and in
the Appendix of the Official copy of this Final Report. (Appendix E) The questionnaire was not
a scientific or statistically valid survey, as noted in a statement contained at the top of the
questionnaire.

The last several meetings were devoted to reflecting on what had been learned and to writing
this report so that it would be most useful to the four chairmen and their organizations. This
report attempts to provide clear recommendations, though consensus was not achieved on all
issues.

III. History and Current State of the Reservoir.

The City of Charlottesville purchased the land for the Reservoir in 1962, and construction of
the Reservoir and the South Fork Rivanna River Dam was completed in 1966 when the

5
Reservoir was filled.3 As constructed, the surface of the Reservoir comprised 390 acres with a
watershed of 258 square miles. 4 The Reservoir is serpentine in shape and measures 7 ½ miles in
total length from its dam upstream to Buck Mountain Creek, its official end-point and extent of
City ownership. In the year 2000, it was estimated that, during periods of average rainfall,
74,400 million gallons of water flow into the Reservoir annually. 5 Of this annual inflow, it was
estimated that 2.3% is lost to evaporation; 94.2% passes over the dam or through the hydro-
electric plant; and 3.5% is withdrawn for treatment and community consumption.6

Interestingly, Stephen Bowler opined in his Report, “South Fork Rivanna Reservoir and
Watershed; Reflecting on 36 Years, Anticipating 50 Years,” that the Reservoir is neither a “lake”
nor a “river” but falls somewhere between these two designations.7 This is due to enormous
water flow through the Reservoir, flow that transports considerable sediment especially during
storm events that erode stream banks. Some of this sediment drops out when the river flow is
slowed upon reaching the Reservoir. Also as suggested by Mr. Bowler, the Reservoir’s riverine
“personality” simultaneously provides both a “blessing” and a “curse.”8 The “blessing,” of
course, is abundant water supply and the “curse” is sedimentation.9

The placid present appearance of the Reservoir belies its turbulent first days. As described by
former County Supervisor, Charlotte Y. Humphris, the first of several fish kills occurred in 1969
resulting in a public outcry about the terrible taste and smell of the Reservoir water.10 This initial
fish kill and several others in the same year were probably the result of pollutants causing low
night-time dissolved oxygen levels. 11 Other fish kills occurred in 1970 and 1972.12 According

3
“South Fork Rivanna Reservoir and Watershed, Reflecting on 36 Years, Anticipating 50 Years,” Bowler, Stephen
P., 2003, [hereinafter, “Bowler”] (Appendix F at page 3)

The Task Force (and community) is indebted to Mr. Bowler for his definitive history and technical analysis of the
Reservoir, written in year 2003, while Mr. Bowler served as County Watershed Manager. At the time, responsibility
for compensation for the Watershed Manager’s position was shared by the County and the RWSA.
4
“Bowler,” (Appendix F at page 5)
5
Id. at page 7.
6
Id.
7
Id. at page 12.
8
See, “Bowler,” (Appendix Fat page 32)
9
It is noted in passing that under the approved Water Supply Plan, the new Ragged Mountain Reservoir, will be
connected to and filled by a pipeline from the South Fork Rivanna Reservoir, providing the “blessing” of water
supply, but without the “curse” of sedimentation. Also, the Ragged Mountain Reservoir is protected from any
residential development around its rim.
10
“A Summary of Efforts to Protect the South Fork Rivanna Reservoir 1965-1999,” Humphris, Charlotte Y.,
[hereinafter, “Humphris”] (Appendix G at page 1)
11
“Bowler,” (Appendix F at page 38)

6
to Ms. Humphris’s account, “finger pointing” soon began. The City was blamed for not
purchasing enough land around the Reservoir site to adequately protect it. However, the County
had no zoning ordinances in effect during the early days to protect the Reservoir and took the
position that it had no obligation to protect the “City’s” water supply. When the County did first
adopt a zoning ordinance, it proposed high-density zoning adjacent to the East end of the
Reservoir.13

In spite of this difficult beginning, however, there was swift progress in Reservoir protection.
Numerous experts were retained over the years to provide reports, studies and recommendations,
and the County adopted stringent land use protections. This progress is fully documented in
Mr. Bowler’s report and in Ms. Humphris’s paper and will not be recounted here, except to note
several particularly significant developments. A significant event was the County’s 1980 down-
zoning of the rural area, which prevented high density development in order to protect the
watershed. The initial plan for high density development adjacent to the Reservoir was
abandoned in favor of low density, large-parcel development.14 Also of particular significance,
the Crozet Interceptor was completed in 1985, thus removing inadequately treated industrial and
residential sewage that had previously impacted tributaries of the Reservoir. Albemarle
County’s water protection ordinances that evolved represented a model for other jurisdictions to
follow.15

Nevertheless, since the inundation of the river in 1966, natural forces have worked to return
the Reservoir to a more river-like state. As documented for the Task Force by Greg Harper in
his presentation and paper, “The Loss of Water Surface and Formation of Land in the South Fork
Rivanna Reservoir,” sedimentation of the Reservoir has been relentless.16 This was expected at
the time the Reservoir was constructed in 1966, when it was estimated that storage capacity in
the Reservoir would be lost at the rate of 19.6 million gallons per year.17 In fact, however, the
loss has been much less, with an average annual loss of storage capacity of 15.6 million gallons

12
Id.
13
“Humphris,” (Appendix G at page 1)
14
Some might argue that even to allow large parcel residential development around the Reservoir was a
compromise, and that the better course, to more fully protect the Community’s future water supply, would have been
to allow no development around the perimeter of the Reservoir. It does not presently appear that this ever was a
politically practical alternative.
15
From time to time the complaint is heard, that after construction of the Reservoir in 1966, the City and the
County turned their governmental backs and walked away, willfully leaving the Reservoir to deteriorate. When the
complete historical record is examined, however, it shows that this community has invested millions of dollars in
reservoir protection, as well as enormous time and effort. Also, rural area property owners sacrificed greatly from
the 1980 down zoning which limited future subdivision of parcels and development, an action the County was
required to defend in the Supreme Court of Virginia, and subsequently won. In spite of these measures, sediment
continues to fill in the upstream reaches of the Reservoir.
16
“The Loss of Water Surface and Formation of Land in the South Fork Rivanna Reservoir,” Harper, Greg, 2008
[hereinafter, “Harper”] (Appendix H)
17
“Bowler,” (Appendix F at page 14)

7
per year.18 Whether the initial estimates of storage loss were too high, or the extensive water
protection efforts implemented over the years were in part successful in reducing sedimentation,
is unknown. The Reservoir has a "dead storage" area immediately upstream from the dam,
designed to receive sediment from upstream. But due to the Reservoir’s long, narrow shape, the
entering water slows down and drops sediment long before it reaches the dam, causing the
upstream portions to be most affected by sediment.

Rather than plotting Reservoir storage volume loss in millions of gallons per year, however,
Mr. Harper’s analysis focused upon the amount of pool surface area that has been lost due to net
deposition of sediment in spite of the small amount of pool surface area gained by bank cuts and
erosion. By applying GIS measurements to aerial photographs of the Reservoir from 1974 and
2007, Mr. Harper was able to estimate the amount of pool surface area lost between 1974 and
2007, and with the data, make projections of the additional pool surface area that would be lost
between now and year 2057. Mr. Harper's analysis focused upon two areas of the Reservoir—
the Ivy Creek area and the main body of the Reservoir upstream from the Earlysville Road
Bridge. (See Harper’s paper in Appendix H for photographs)

With respect to the Ivy Creek area, Mr. Harper concluded that this area has lost 5.1 acres of
pool surface since 1974 because of sedimentation. He also estimated that between the present
and year 2057 an additional 7.7 acres of pool surface area will be lost if there is no
intervention.19 He further concluded that by 2057 the Ivy Creek portion of the Reservoir will
have reached a sediment-equilibrium and have restored itself as a creek.20

Mr. Harper further concluded that in the main body of the Reservoir (upstream of the
Earlysville Bridge) 17.2 acres of pool surface has been lost since 1974, and that an additional 26
acres will be lost by year 2057 without intervention and if sedimentation continues at a constant
average rate.21 He emphasized that his technique is based on aerial photographs and cannot
determine changes in the water depth; these projections simply extrapolate the past rate of
surface area loss into the future. He also opined that between now and 2057 the Reservoir will
narrow as the stream seeks a state of equilibrium with respect to sediment.22

Mr. Harper’s observations, however, do not quantify the amount of Reservoir storage capacity
volume that has been lost already nor the volume that will be lost by 2057. A better indicator of
storage capacity loss due to sedimentation is obtained from bathymetric studies, the last of which
was conducted in March 2002. Based upon those data, it is estimated that the Reservoir’s usable
storage has dropped from 1,250 million gallons at the time of construction (1966) to 800 million

18
Id.
19
“Harper,” (Appendix H at page 3)
20
Id.
21
Id. at page 4.
22
Id. at page 5.

8
gallons in 2002, and Gannet Flemming predicts that storage will further decrease to
approximately 200 million gallons in another 50 years.23

Recently, hydrilla, an invasive, non-native underwater plant has become established in the
Reservoir, particularly in the upstream reaches. As noted in the discussion below, hydrilla’s
growth is a matter requiring close attention by RWSA.

IV. Benefits of the Reservoir To The Community.

The Reservoir continues to benefit the community by providing drinking water supply and
drinking water storage as it was constructed to do. As the decades have progressed, other uses
and benefits of the Reservoir have emerged. This section lists these beneficial uses and serves as
a basis for Section IV, which recommends potential measures to preserve (or enhance) these
beneficial uses into the future.

Drinking Water Supply

As noted above, the South Fork Rivanna Reservoir can be described as somewhere between a
river and a lake. During normal periods of average rainfall, the Reservoir’s riverine
characteristics provide a primary benefit to the community. The water intake located near the
dam functions as a “run-of-the-river” intake, where water is taken from the river before it passes
over the dam or passes through the hydroelectric power plant. The vast majority of the
community’s drinking water—both now and in the future—is produced in this fashion. The
water intake in the Reservoir is the principal source of drinking water supply to the Urban
Development Area of the County and the City of Charlottesville.

The South Fork Rivanna River flowing into the Reservoir drains a 258 square mile watershed,
and under the Water Supply Plan, it will continue to be the principal source of this community’s
water supply for the foreseeable future. About 96% of the urban water supply comes from the
South Fork Rivanna River’s watershed, now and in the future (the rest is from the North Fork
watershed with a small amount --0.3% --from the Ragged Mountains watershed). The function
of the Reservoir as a reliable source of water is a critical, most important benefit of the Reservoir
to the community. 24

Drinking Water Storage

During periods of drought, the other part of the Reservoir’s “dual personality” becomes more
critical. As flow into the Reservoir slows, the community benefits from the Reservoir’s lake

23
Letter, dated June 15, 2005, from Gannett Fleming to RWSA, re: “Potential Dredging of the South Fork Rivanna
Reservoir (SFRR).”
24
Charlotte Humphris recorded a poignant statement by an official of the State Health Department made in the
early 1970s. According to Ms. Humphris, Assistant Resident Engineer Stephen Young stated, “Charlottesville
doesn’t really have another water source. The Rivanna is the life of Charlottesville.” (“Humphris,” Appendix G at
page 3)

9
attributes. The Reservoir stores water to be utilized during dry periods when the abundant inflow
to the Reservoir is reduced. The South Fork Reservoir provides about 50% of the current water
system’s storage capacity, down from 59% at its creation. Sedimentation over the past 42 years
has reduced the Reservoir's storage capacity. With the approved Water Supply Plan, and without
the additional expenditure of community funds for dredging, the benefit to the community
provided by Reservoir as a water storage mechanism will continue to diminish.

As described by the Water Supply Plan, however, the expanded Ragged Mountain Reservoir
will provide additional and sufficient water storage capacity to meet community needs through
2050. Upon completion of all components of the Plan, the Reservoir will be depended upon to
provide only about 7% of the community’s water supply storage capacity. Thus, while the
community will continue to rely on the Reservoir’s characteristics as a river to supply its water,
it will no longer need to rely on the Reservoir’s characteristics as a lake to store most of the
water needed during times of drought. That storage role will be assumed by the newly expanded
Ragged Mountain Reservoir.

Drinking Water Quality

The Reservoir benefits the community by providing high quality water. All samples of
RWSA’s finished drinking water from the Reservoir are in 100% compliance with United States
Environmental Protection Agency and Virginia Department of Health Standards.25 As discussed
in Section III above, the watershed of the Reservoir is almost completely rural, and much of it is
forested. There are no significant industrial land uses in the watershed that might contribute
chemical pollutants. Watershed protection is an on-going concern of Albemarle County and is
expressed in its land use practices and ordinances, and it is highly unlikely that any type of high-
density residential development will be allowed in the Reservoir’s watershed.

Nevertheless, sediment accumulation, depleted oxidation status, and turbidity can impact the
quality of Reservoir water. The components of Reservoir sediment are known from only a few
samples but appear consistent with normal Piedmont soil and do not contain metals or pesticides
to any significant degree. The Reservoir, however, does have nutrient levels that can lead to
algae blooms, poor light transmission to aquatic plants, and low dissolved oxygen levels in
certain weather conditions. In warm months, aggressive water treatment is sometimes necessary
to remove taste and odor compounds (algae, manganese, and iron) and to compensate for low
dissolved oxygen in the raw drinking water.26 All in all, however, the Reservoir benefits the
community with high quality water. The Task Force notes, given the decision by the community
to design its future water supply to draw water from its own watershed, almost all of which is
within protected County borders, that the quality of Rivanna River water will continue to be an
important benefit to and important responsibility for the community.

25
Presentation to Task Force by Dr. Robert Wichser, RWSA, August 12, 2008, (South Fork Rivanna Reservoir
Stewardship Task Force Minutes [hereinafter, “Minutes”], August 12, 2008, Appendix D at page 9)
26
Id. at page 9-11.

10
Competitive Collegiate Rowing and Recreational Rowing

From the earliest days, the Reservoir has provided the benefit of a sports venue for
competitive and recreational rowing. The University of Virginia's Women’s Rowing Team (a
UVA varsity sport), the UVA Men’s Rowing Club (self-supported), and Community rowers
(members of the Rivanna Rowing Club) all regularly use the Reservoir from a boat house and
dock near the Woodlands Road/Earlysville Road bridges. Rowing and the other water
recreational uses of the Reservoir have continued to increase and expand until it is the most
utilized body of water for recreational pursuits in this community. It is estimated that more than
50,000 person-hours per year are expended in Reservoir rowing activities alone, comparable to a
rough estimate of 60,000 to 75,000 recreation hours spent at each of the other County lakes and
reservoirs. As discussed more fully in Section V below, continued sedimentation of the
Reservoir constricts the area available for rowing. At some time in the future the University
program may have to consider moving to another location.

Fishing

The Reservoir is generally viewed by sports fishermen as the best fishing spot in the County.
The Reservoir contains self-supporting populations of largemouth bass, bluegill, red-ear sunfish,
black crappie and channel catfish. Thirty-pound catfish are rumored to live there. There are
approximately 7000 active fishing licenses issued in Albemarle County, and John Kauffman
(Virginia Department of Game and Inland Fisheries) estimates that the Reservoir hosts 13,000 to
20,000 individual angler trips per year.

Paddling

Canoeing and kayaking (often coupled with fishing or birding) are also popular activities on
this Reservoir that offers the longest stretch of flat water in the region. Sedimentation has
resulted in very shallow water in some areas, thus limiting access to even very shallow-draft
boats, but the total surface area of the Reservoir is extensive and otherwise accessible to canoes
and kayaks. The most limiting factor to these activities is lack of adequate public access to the
Reservoir. The owners of private property on the Reservoir do have access and are allowed to
build boat docks for small un-motored craft under tightly controlled regulatory conditions.

Education

The Ivy Creek Natural Area, located at the convergence of Ivy Creek with the Reservoir, is
owned jointly by the City of Charlottesville and Albemarle County and provides unique
opportunities for nature study and education due to its location on the Reservoir and Ivy Creek.
Classes and programs at the Natural Area are offered by the Ivy Creek Foundation. Also,
summer camps for children are provided at Panorama Farms, a privately owned property located
on the north side of the Reservoir. Because the Natural Area and the Reservoir offer natural
settings that support local flora and fauna, a variety of groups use the area for educational
purposes.

11
Ivy Creek Foundation’s educational programs are designed to observe and interpret changes
in the natural world. Although sediment accumulation in the portion of Ivy Creek immediately
adjacent to the Ivy Creek Natural Area has changed the shores of the Natural Area, dredging this
section of Ivy creek to restore the original channel is not necessary for the continuation of these
educational programs. If reservoir maintenance projects such as mechanical removal of hydrilla
or opportunistic dredging were instituted, Foundation representatives have opined that efforts
would be made to minimize any negatives impacts these measures might have on their
programming and on public use of the Natural Area, and that their curriculum may be adapted to
incorporate these maintenance activities where appropriate.

Aesthetic Value

When the Reservoir construction began in the early 1960’s, a beautiful 7-mile stretch of the
South Fork Rivanna River was destroyed -- a stretch that was free-flowing and natural and had
importance to local residents and others at the time. There was undoubtedly sadness when the
river was inundated and the Reservoir formed, but we have no historic record of
contemporaneous observations.27 Even though some initial ugliness may have resulted from the
construction activities, the 42-year old Reservoir is now a beautiful body of water. The
Reservoir is a Community amenity for all who observe it from bridges, on the water, or from
neighboring properties. Lack of access to the Reservoir limits its full appreciation.
Sedimentation in the Reservoir has certainly changed the "picture" of what the Reservoir looks
like, especially in the upper reaches of the Reservoir as well as the Ivy Creek portion of it.
Islands have formed; shrubs and trees have filled out the islands. Though these are natural
processes, it is impossible to conclude whether this has improved or lessened the aesthetics of the
Reservoir. With beauty being in the eye of the beholder, it is likewise debatable whether
dredging would improve, or damage, the Reservoir exclusively from the aesthetic perspective.

27
While beyond the scope of the Task Force report, a few historical items are worthy of note and form part of the
value of the Reservoir to our Community. Don Wagner, Chairman of the ACSA, recalls that at some time prior to
1959, the Hydraulic Sand and Gravel Company was located at the edge of the Rivanna River near where old bridges
crossed Ivy Creek and the Rivanna River, close to where the Woodlands Road and Earlysville bridges currently
cross the Reservoir. The Hydraulic Sand and Gravel Company mined sand and gravel from the Rivanna River. This
is testament to the power of the Rivanna River to move sediment from upstream locations even before the Reservoir
“captured” the sediment.

Hydraulic Mills, once located at the juncture of Ivy Creek and the Rivanna River, played an important role in
local history. John Perry purchased the mill in 1818, from which he supplied much of the lumber used to build the
University of Virginia. By the mid-19th century, Hydraulic Mills had become the head of navigation for the Rivanna
River, and the mill complex included a grist and merchant mill, a miller's house, a cooper's shop, a storehouse, a
blacksmith's shop, a country store and, briefly, a silkworm industry. Farmers from throughout northern and western
Albemarle brought wheat and tobacco to be processed here and sent down-river by bateaux to Richmond and
beyond. In the mid-1880s, Hydraulic became the commercial and social center for the growing African American
neighborhood known as Union Ridge. When completed, the South Fork Rivanna Reservoir flooded the junction of
Ivy Creek and the Rivanna River, erasing all vestiges of this once vital community center. Also, it is known that
there were ancient Indian settlements in the general area of this portion of the Rivanna River.

12
Biota

The Reservoir provides a variety of ecological habitats from lake to wetlands. The Task Force
didn’t investigate what is known about the Reservoir’s invertebrates. Fish are thriving (see
above). Turtles and birds abound as well as some aquatic mammals. Hydrilla (Hydrilla
verticillata), an invasive aquatic plant that is thriving in shallow waters throughout watersheds in
the Southeastern United States has recently taken hold in the Reservoir. While hydrilla provides
benefits such as nutrient-filtering and fish habitat, John Kauffman notes that it can create habitat
problems when it covers more than 30% of a body of water. It is now a serious issue for rowers
especially where it forms thick mats, according to Kevin Sauer, long-time Head Coach for UVA
Women’s Rowing. Its growth depends on light for photosynthesis, but it survives in lower light
conditions than most plants and can grow to depths of 15 meters in clear water. Hydrilla is
especially problematic during infrequent periods when water level is below dam height because
then the plants lie sideways and can be especially impenetrable to boats. If it becomes too
pervasive within the reservoir, it can also adversely affect fish habitat and water quality
especially by absorbing too much oxygen. Its growth is a matter requiring close attention by the
RWSA and Reservoir users.

At least one Task Force member has mentioned the possibility of breaching the Reservoir’s
dam to allow the river to flow naturally. One advantage of such a breaching would be the
potential return of the American eel and American shad, gizzard shad, and herring to the upper
reaches of the South Fork watershed. Shad and eels spend a portion of their life cycles inland
and a portion in the ocean – and dams prevent their access to critical upstream habitat.

V. Measures To Maintain Community Benefits.

Each of the community benefits listed above has some value, is threatened to a certain degree,
and is worth some community effort to preserve or enhance. How great the value, how imminent
and substantial the threat and how significant the investment we should make to maintain those
benefits is for accountable local officials to decide. While the Task Force is not in a position to
determine how the benefits of reservoir maintenance compare to other community priorities, we
have educated ourselves on these issues and can suggest how the risks can be assessed by the
elected officials and the two water-supplying authorities. We can imagine that the rate-payers
and/or tax-payers will want a clear analysis of the cost/benefit of any maintenance activities,
whether dredging out sediment or implementing measures to keep sediment from entering the
Reservoir. In short, the Task Force can describe why and how we should maintain the Reservoir,
but only accountable local officials can determine when such measures might be implemented,
and whether it would be worth the cost. Accountable local officials may also decide to take no
action, of course.

Removing Sediment from the Reservoir

Over time, the continued accumulation of sediment will affect beneficial uses of the South
Fork Rivanna Reservoir. Specifically:

13
· Each year, sediment accumulation reduces the storage capacity of the South Fork
Rivanna Reservoir.
· Each year, sediment accumulation restricts the area accessible to rowers, paddlers and
boating fisherman.
· In roughly seven years, the UVA competitive rowing team may have to consider whether
to move from this venue.
· In roughly 50 years, an estimated 33 acres of new land could form within the 390-acre
Reservoir.
· In roughly 75 to 100 years, accumulated sediment in the dead storage area at the dam
may clog the existing water supply intake and necessitate dredging in this area.

Water Storage. Past bathymetric studies clearly show that storage capacity has been
diminished by sedimentation, and it is expected to diminish further as time progresses. The
approved Water Supply Plan—which the Task Force was charged to accept—already accounts
for that diminishing storage capacity of the Reservoir. Therefore regaining lost storage capacity
is not a reason to dredge or slow sedimentation, but it is undeniably a benefit created by dredging
or slowing sedimentation undertaken for whatever reasons. Maintenance dredging for any
purpose would result in additional supplementary water storage capacity. Thus, the ancillary
benefit of expanding water storage capacity by dredging should be factored into any
consideration of dredging for other purposes. For example, if the community were to decide to
continuously dredge to improve boater access to the Reservoir, this will also create additional
water storage, which may result in the water supply, planned to meet needs for 50 years, actually
meeting community needs longer than 50 years.

The Task Force discussed storage capacity benefits that might ensue in the short term and in
the long term resulting from dredging, even if primarily for other purposes. In considering the
short term, i.e. prior to completion of construction of the new Ragged Mountain Dam and
Reservoir and the SFRR to Ragged Mountain pipeline scheduled for 2021, the Task Force
discussed whether dredging in the near-term that resulted in additional capacity would reduce the
risk of water storage shortages that might occur if demand exceeds planned capacity before 2021
or because of unexpected delays in the completion of the Ragged Mountain Dam and pipeline; or
in the case of a drought of record in the interim.

Creating any additional storage capacity in the Reservoir would of course reduce risk during
drought periods in the short-term. The Task Force was told by RWSA that the computer
modeling that supports its drought-management strategy shows that the system has adequate
capacity without dredging to meet community needs between now and 2021, even during a
severe drought.28 This would seem to allay the short-term risk concerns, but some members of
the Task Force believe since this was not directly studied by the Task Force, officials should
assure themselves that this risk is minimal. Other members of the Task Force have suggested,
however, that to the extent that any short term risk exists, this risk can be ameliorated by earlier
construction of the pipeline from the Reservoir to the newly enlarged Ragged Mountain
Reservoir(s). If the short-term risks are a community concern, other drought-responses may be

28
The Community drought management strategy, revised in 2006, now includes releasing water from the Beaver
Creek Reservoir into the Mechums River, thence into the Reservoir.

14
appropriate, but the Task Force has not gone outside its charge to look at any other possible
measures. If short-term risks are judged to be a significant concern, and if other reasons for
dredging combine with that concern, the Task Force suggests in the final section of this Report a
procedure for consideration of a modest level of dredging.

Rowing, paddling and fishing access. Removal of accumulated sediment would extend the
range of access for rowers, paddlers and fisherman. As the Reservoir reaches sediment
equilibrium, however, sediment will no longer accumulate in the main channel of the Reservoir,
keeping that area open for these uses. Whether the remaining area of deep water sufficiently
meets the demand of these users is unclear. In addition, paddling and other recreational boating
activities are affected by the increasingly shallow areas caused by sediment, separate from the
rowers’ need for an open channel.

UVA’s competitive rowing program. On August 22, 2008, the Task Force conducted a field
trip to the Reservoir escorted on boats provided by the UVA rowing program. At the time, the
Reservoir was approximately 3 feet below its normal pool level due to exceedingly dry
conditions. In normal rain-fall years, it is relatively rare for the Reservoir to be below its normal
pool level, and, due to the very large size of the Reservoir’s watershed, the Reservoir tends to
refill rapidly after such events, as it did shortly after the field trip.

On the field trip, sandbars and islands created by sedimentation were evident upstream from
the University’s Boat House and immediately downstream from Ivy Creek. Hydrilla was very
evident. Kevin Sauer estimates that 1½ miles of practice area that his crews used to enjoy have
been lost to sedimentation.

The risk here is that the UVA and other competitive rowing programs will be increasingly
constricted in practice area and might need to consider moving from this venue. There are 3,000
meters from the boathouse to the dam that is expected to remain clear, but ideally rowers would
have a 100-foot lane clear, up to Reas Ford Bridge, allowing a total of 4,800 meters. Kevin
Sauer does not think that the UVA teams will have to consider moving for at least another seven
years. The risk to the University of Virginia and other competitive rowers of losing its
competitive rowing venue should be weighed along with determining what amount of dredging
will be needed to restore adequate rowing lanes in some areas. The situation requires close
monitoring. If the community determines that the risk of loss of competitive and other
recreational uses as discussed below are sufficient to require immediate dredging, Section VII
discusses Next Steps to be taken.

Wetlands creation. Another storage capacity issue is a long-term one and is based on the
proposition that maintenance dredging could be used to preserve the Reservoir adequately so that
it might provide more storage in another 50 years, to respond to the risk that additional storage
capacity might be needed then. Some Task Force members suggest that since wetlands constrict
the storage capacity, if they were to become un-touchable by regulations, storage capacity would
be permanently lost or too costly to restore. They suggest that dredging these shallow
depositional areas now may be prudent before that potential loss. Other Task Force members
expect that mitigation would be required but removal would be allowed if sufficient need were

15
proven. Information will need to be obtained from Federal and State regulatory officials to
determine whether this concern of permanent loss is warranted.

The Task Force did not analyze the severity of the risk that this type of dredging will be
permanently curtailed, nor the need for using the Reservoir for additional storage capacity after
50 years, but it suggests this type of risk analysis be done by RWSA with experts on this specific
issue.

Removing Debris from the Reservoir.

The Task Force didn’t investigate physical maintenance such as removing fallen trees and
snags that foster the creation of sandbars by slowing the flow of water. But recreational users
point to these as a sign that no one is responsible for ongoing maintenance as would be found in
a purely recreational lake. The Reservoir users might respond to the offer of an open dialogue on
the issue of on-going maintenance.

Abating the Effects of Hydrilla.

The recent onslaught of hydrilla has created problems for rowers, paddlers and fisherman and
has the potential to affect fish and water quality. Nation-wide, scientists are working to find
ways to fight this invasive plant, without much success. RWSA and recreational users may have
to work together to restrict its growth if the extent of the hydrilla begins to restrict severely the
recreational uses of the Reservoir and threaten water quality. 29

Keeping Excess Nutrients Out of the Reservoir.

As discussed in Section IV above, there is no serious current threat to Reservoir water quality
from industrial pollutants and run-off, due primarily to 40 years of County land use planning to
protect the watershed. Run-off from agricultural fields and homes, however, is believed to
contribute quantities of phosphorous and nitrates which impair water quality to some extent. At
certain times these chemicals tend to promote the growth of algae, which causes taste and odor
problems that require additional water treatment.30 As the nutrients “ride in” on the sediment
and are released into the Reservoir water or deposited with the sediment, dealing with sediment
would go along way towards reducing nutrient problems. Educating landowners about proper
application of fertilizers also would help the Reservoir.

29
Many research articles are being written regarding hydrilla. It is not clear that dredging would do anything but
further increase its presence, due to its ability to reproduce and survive in waters shallower than 15 meters. It can
reproduce from cut segments, flower, root, tuber and axial seeds. Any maintenance dredging operation or other
maintenance activities conducted in the future should take the presence of this nuisance into account, and the
expansion of hydrilla should be monitored closely. (“Summary of Information on Hydrilla,” Ambler, Tamara,
January 8, 2009, Appendix I)
30
It is further noted, that in the early part of this decade, Albemarle County Police Department divers retrieved 3
automobiles from the bottom of the Reservoir at the Woodlands Road fishing ramp. Though in heavy use by
sportsmen, this ramp makes the Reservoir vulnerable to misuse such as illegal dumping.

16
Keeping Sediment Out of the Reservoir.

Presently, the greatest threat to Reservoir water quality is the large amount of sediment that
enters the Reservoir every year. Measures to decrease the sediment are on-going and should be
continued. The County has over the years implemented increasingly aggressive water protection
ordinances supported by citizens who are concerned about the health of waterways. 31 It is
difficult to quantify the degree of success these ordinance have had, but sedimentation of the
Reservoir has been less than was estimated at the time of the Reservoir’s construction. Most
recently, in February 2008, the County passed an ordinance which allows the County to impose
some regulatory control even on farmed and forested lands in identified “erosion impact areas.”
Notwithstanding the County’s arsenal of water protection ordinances, however, budget
constraints have not allowed the County optimally to staff watershed protection positions, which
can impair aggressive enforcement of its watershed protection ordinances. 32

The recently established Rivanna River Basin Commission (RRBC) is also fully engaged in
analyzing methods to decrease sedimentation and siltation from the tributaries of the Rivanna
River. It has established a Technical Advisory Committee, composed of staff members of the
participating jurisdictions and private citizens with particular and varied scientific expertise. As
time progresses, it is hoped that the RRBC will have considerable impact upon the problem of
sedimentation and siltation which has plagued the Reservoir for 42 years.

There is a voluntary partnership of agencies concerned with sedimentation and other threats to
the waterways. This partnership consists of the RWSA, Stream Watch, the Nature Conservancy,
the Rivanna Conservation Society, the Thomas Jefferson Planning District Commission, the
Thomas Jefferson Soil and Water Conservation District, Charlottesville and Albemarle County
staff, the Rivanna Regional Stormwater Education Partnership, the University of Virginia and the
Virginia Department of Transportation. The Thomas Jefferson Soil and Water Conservation
District offers technical assistance and incentives to rural landowners to protect streams from
erosion and over-land flow of sediment when funding is available. They also offer a
Conservation Reserve Enhancement Program (CREP) and a TJSWCD Riparian Easement
Program to provide permanent protection of forested buffers along streams.

One idea which was discussed is the concept of constructing a forebay at the upstream end of
the Reservoir, perhaps near the Reas Ford Road Bridge. The concept would be to construct an

31
See, Albemarle County Code, Chapter 17.
32
The Task Force did not study possible deleterious impacts that upstream activities can have on the Reservoir. In
the past, major public efforts in the watershed have improved the Reservoir. The Crozet Interceptor was the largest,
taking wastes from a former food-processing factory as well as residential wastewater from the Crozet area, out of
the Reservoir’s watershed. Crozet’s Lickinghole Creek Basin was built to collect storm water runoff from that area,
further protecting the reservoir’s tributaries. There also has been a ban on phosphorous in detergents which had
clear effect. No major efforts of similar nature are currently being considered, except that restoring flow to the
Moormans River, as will be accomplished under the permit for the Water Supply Plan, will have a beneficial effect
on the Reservoir once the Plan is fully constructed. This further community benefit of the approved and permitted
Water Supply Plan, which restores flow to the Moorman’s River and protects flows below the dam in the South Fork
Rivanna River, should not be underestimated. Indeed, it can be said that these sustainability features mark who we
are as a community.

17
area that would serve to slow the flow of water incoming to the Reservoir sufficiently to cause
major amounts of sediment to “fall out” before leaving the forebay and entering the Reservoir.
The forebay itself, of course, would need to be periodically dredged or excavated to remove
sediment that is captured, probably necessitating an access point in the Reas Ford Bridge
vicinity. (See discussion in Section VII below, regarding next steps including a “regulators” site
visit.) The RRBC might be able to provide technical support for examination of such a concept
which could have application in other areas of the multi-jurisdictional watershed, including
upstream from the Reservoir.

Improving Reservoir Access

The launch ramp at the Woodlands Road bridge is presently the only public access to the
middle reaches of the Reservoir for fishermen and other small boaters, and its location is
hazardous for those launching or offloading boats as well as local traffic. The City-owned access
near the dam is avoided by boaters because of its steep drop-off into the water. Albemarle
County plans a new boat-access near the dam, but will not have capital funding until after 2014.
Private funds or donation of private land for additional access should be encouraged. If
community resources are to be used to improve any users’ recreation opportunities at the
Reservoir, access for the public should be improved. Also, channels should be cleared of
downed trees especially after storms since snags create sediment bars. Any approach ramps,
such as may be needed for maintenance equipment, should be designed to become public access
points if located in an area that can be made safe for cars, pedestrians and boats.

Supporting the Ivy Creek Natural Area.

The Ivy Creek Natural Area is uniquely situated to be a center for study of the Reservoir
as a natural resource. Jointly owned by the City and the County, the Ivy Creek Natural Area
provides an educational venue for the Ivy Creek Foundation (a non-profit organization), which
conducts nature tours for school children, hosts educational programs that are free and open to
the public in the old barn and the newer Education Center (which is also used by other local
groups). The Foundation also maintains the trails for public use and works to foster partnerships
in environmental and natural history education with other non-profits, area schools, community
groups and the University. The Foundation welcomes public and private funds to help with staff
and programs, as well as upkeep and upgrades to the public facilities at the Natural Area and this
should be encouraged.

VI. Results of Not Implementing Suggested Measures.

This section discusses the effect that not implementing the suggested measures would have on
the beneficial uses of the Reservoir identified by the Task Force.

Drinking Water Supply. As long as water continues to flow into the Reservoir, it will be the
predominant source of our drinking water. As has been described, the South Fork Rivanna
Reservoir will continue to receive sediment along with its copious supply of fresh water. In
roughly 75 to 100 years, the area around the present intake will need to be cleared.

18
Drinking Water Storage. No maintenance of the Reservoir is necessary for meeting the
community’s water storage needs in light of the Community Water Supply Plan. If no
maintenance is performed, an estimated 33 acres of land are likely to form in the reservoir. This
may, or may not, affect the future expansion of the reservoir, if needed beyond the 50-year
Community Water Supply Plan. (See discussion at page 14).

Drinking Water Quality. If the amount of sediment and nutrients entering the Reservoir is not
reduced, we will not be able to reduce the amount of chemical treatment needed and thereby
reduce our water treatment costs. If local organizations and agencies cease to work to maintain
the river’s health, and/or if the County changes its zoning and ordinances to allow more suburban
and industrial development in the watershed, the quality of the water could be seriously
impacted. Almost uniquely, our community’s public water flows from within our own
boundaries. We have the ability to be stewards of our own water; we have no one to blame but
ourselves if we allow degradation of the Rivanna River and its headwater tributaries.

Competitive Rowing and Recreational Rowing, Paddling and Fishing. If measures are not
taken to remove sediment or reduce the rate of sedimentation, the UVA competitive rowing team
will likely have to find another venue for practices and meets, some time after seven years.
Similarly, the area available for recreational rowing, paddling and fishing will continue to
decline until the Reservoir reaches a state of sediment equilibrium. At that time, the Reservoir
will resemble a wide river rather than a lake. The spread of hydrilla and the existence of debris
in the Reservoir also restrict access to portions of the Reservoir for rowing and paddling.
Finally, if public access is not improved, a decreasing proportion of the population will be able to
utilize and appreciate the Reservoir. (Other lakes will undoubtedly be turned to, including the
newly expanded Ragged Mountain Reservoir, to the extent that public access is allowed.)

Education. No reservoir maintenance is required to maintain the educational benefits of the


Reservoir, but improved public access could increase educational opportunities.

Aesthetic Value. In the absence of maintenance, floodplains will form where sediment is
deposited along the edges of the reservoir, and they will likely resemble the forested floodplains
that existed before being inundated when the reservoir was created. Once the reservoir reaches
sediment equilibrium, it will likely resemble the South Fork below the dam, a State Designated
Scenic River.

Biota. There is little evidence that maintenance is required to preserve habitat in the
reservoir, although the habitat will become more river-like than lake-like and hydrilla will
probably become more pervasive.

VII. Next Steps.

The Task Force hereby recommends the following “next steps,” consistent with the Task
Force mandate which places the fundamentals of the Water Supply Plan beyond the Task Force

19
purview, and thereby precludes consideration by the Task Force of dredging solely to expand
water storage capacity.

A. Investigate the Impact of the Encroachment by Wetlands.

The Task Force recommends that several specific aspects of the potential post-50 year risk be
addressed by RWSA with consultants. One aspect is whether the Reservoir’s inflowing sediment
is now, and is likely to be, creating wetlands. “Wetlands” are extensively defined by Federal
regulation. Experts can determine whether wetlands are forming in and around the edges of the
Reservoir as defined by regulations of the U.S. Army Corps of Engineers and the Virginia
Department of Environmental Quality. The behavior of the water flow in this river-like reservoir
might be significant in determining whether wetlands will form.

If wetlands are forming or likely to form that constrict the Reservoir, we should determine
whether removal of such wetlands is likely to be permitted in the future, when additional water
storage capacity may be needed. RWSA should seek legal advice regarding the likelihood that
future removal of such created wetlands would be permitted in order to expand drinking water
storage.

After ascertaining the existence and potential of wetlands, it is recommended that appropriate
personnel from the Virginia Department of Environmental Quality and the U.S. Army Corps of
Engineers be invited to conduct an “on the water” site visit of the Reservoir. The purpose would
be to evaluate the Reservoir for particular areas that potentially could be dredged for
maintenance purposes. These areas may include places where the pool surface area has already
been lost to sedimentation and areas near the shorelines that are becoming shallow due to
sedimentation, but where the sediment has not yet breached the surface of the pool at normal
Reservoir pool levels. The purpose would be to obtain regulatory guidance regarding whether
Federal and State permits would be necessary to conduct maintenance activities by dredging in
these identified areas, and to address the question of whether delaying maintenance dredging
would preclude future dredging or entail additional regulatory burdens.

The survey of the Reservoir and consultation with regulatory officials would be coordinated
by the RWSA, which (before or after the regulators' visit) may wish to consult legal counsel with
experience in water supply regulatory matters. Additionally, information could be gained from
these regulatory officials with respect to regulations that pertain to the construction of a forebay,
as referenced in Section V above, relating to “drinking water supply,” and advise RWSA on the
practicality of a forebay in that specific location.

B. Begin a dialog with the University of Virginia and Recreational Users.

It is recommended that the City, the County, the RWSA and the ACSA maintain a dialog with
the University of Virginia, probably through the Planning and Coordination Council (PACC) to
monitor the University and other competitive rowers’ needs with respect to maintaining a
continuous length of adequate depth for competitive rowing programs. Groups providing other
recreational programs and individual recreational users of the Reservoir should be involved in

20
the discussion when possible. If there is perceived value in the recreational pursuits provided by
the Reservoir, then the community must decide whether an investment in its future is important.
If the University determines that dredging will be necessary to continue use of the Reservoir,
instead of moving its program elsewhere, the University should be requested to provide its view
of when this maintenance would need to be accomplished. Maintenance short of dredging, such
as removing snags that foster the creation of islands, should be discussed, with the goal of
keeping the waterways as open as possible for all the users. This venue could be used to discuss
hydrilla since at this time it interferes more with recreation than with water-quality.

C. Support Efforts to Reduce Sedimentation and Excessive Nutrients.

The Task Force urges continued Community efforts to reduce sediment and pollutants
entering the Reservoir, such as supporting agencies and organizations that are concerned with the
sedimentation problem and the health of the watershed. We encourage strengthening and
enforcing water protection ordinances and programs such as those of the Thomas Jefferson Soil
and Water Conservation District.

Regarding a forebay, RWSA said in answer to a Task Force question, “There may be some
[forebay] strategies that can make some improvement in where sediment drops out, but it is not
likely to find an economical solution that is completely effective. In order to identify the options
in greater detail, or determine if the benefits outweigh the costs, we would recommend retaining
a consulting firm with the expertise to gather appropriate data and develop conceptual
alternatives.” The Task Force did not study the practicalities of a forebay but recommends that it
be pursued at least to the point of having a consultant assess the specific SFRR situation and
advise on its potential, in terms of feasibility, effectiveness and probable cost. Something akin to
forebays but farther upstream than the Reservoir’s slack waters can be part of RRBC’s analysis
of the watershed, with a goal of slowing the storm-created waterflows that scour the stream
banks and deliver sediment to the Reservoir.

D. Monitor the growth of hydrilla and study the most effective way of
managing this invasive grass.

This effort has already begun, but the Task Force was impressed with the rampant
growth of hydrilla and recommends it be closely monitored.

E. Investigate the cost of selective dredging when purposes, priorities and


specifically identified areas have been established

If and when Community decision makers determine the purposes for which dredging
might be done (for example, to prevent wetlands formation after duly studying their legal
status or to facilitate recreational activities), public officials should determine whether the
benefits of any measure to maintain the reservoir are worth the cost of that measure. In
order to assess those potential costs, we recommend that the following actions be taken.

21
1. Identify areas of highest priority for potential dredging, based on
identified purposes

a. Working with University and community rowers, other boaters, and


fishermen, develop a map which clearly identifies the priorities for
specific areas of the Reservoir that would most usefully be kept clear.
b. Identify areas that would need to be dredged to preserve the
Community’s ability to restore the storage capacity of the SFRR
beyond the 50-year Water Supply Plan if wetlands are allowed to
encroach on the Reservoir’s area, should the legal opinion justify such
an operation, and decision-makers consider the risk sufficient enough
to create the need for action.
2. Collect data about high priority areas for potential dredging.

a. Determine whether the presence of obstacles would substantially


increase the cost of dredging (e.g. tree stumps left at the bottom of the
Reservoir when it was constructed). If so, determine whether there are
tree stumps or other obstacles to dredging in the areas of the Reservoir
where dredging would be required to maintain the rowing and
recreational uses of the Reservoir and/or to prevent the formation of
wetlands, should wetlands prevention be necessary. Technology exists
to map contours, presence of underwater aquatic plants and depth of
sediment in specific areas of interest. An intriguing resource is the
aqua-view underwater video cameras used by fishermen on the
Reservoir. Their knowledge of the Reservoir floor could be extremely
useful (and inexpensive to gather) when mapping areas for dredging or
other maintenance such as removing snags.

b. Undertake bathymetric studies in the critical areas for dredging to


quantify the location and amounts of sediment to be removed. Though
RWSA has periodically done bathymetric studies, and this type of
survey of the entire reservoir may continue, it could be done to a finer
degree in the high priority areas of potential opportunistic dredging.
We also note that this step is important to provide data to assess the
effectiveness of any future efforts aimed at reducing sediment inflow
(such as forebays or strengthening of water protection measures). 33

c. Take geotechnical core samples to determine the constituents of the


sediment in the critical areas for dredging.

d. Identify and consider purchasing or optioning one or more potentially


suitable access points, staging areas and dewatering sites on the

33
Of course, RWSA may choose to expand the area of any study if the cost of an expanded study is not significantly
higher and meets other needs, such as regulatory requirements.

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perimeter of the Reservoir that could be utilized by a dredging
company.

e. If relatively small amounts are to be dredged in order to fit a defined


purpose, the Task Force recommends first giving consideration to
“opportunistic” dredging as likely to be the least expensive method.
“Opportunistic dredging” is defined as dredging contracted for when
market conditions make it attractive for contractors to remove dredged
materials at relatively low cost to RWSA (because the profit from
reuse or sale of dredged materials covers the cost of dredging). If
authorities identify other dredging scenarios to fit a defined purpose,
the cost of the method that fits those reasons should be further
analyzed.
f. Estimate the likely duration and impact of dredging operations on
residents and aquatic habitat, including the locations affected, the
presence of equipment and piping, noise or fumes, and hours of
operation, under various alternative approaches.
g. Dredging’s impact on water quality will also need to be considered.
RWSA will need to assess whether its water treatment plant will have
appropriate methods and capacity to handle any of those effects on
water quality, and rigorous safeguards would need to be put into place
to prevent any fuel spills.

3. Finally, based on the information garnered by these steps, and assessing


the community’s risks, infrastructure needs and financial priorities, the
funding authorities should make a decision on whether the public interest
would be served by issuance of a Request for Proposals for removal of
sediment.

*****************

The members of the Task Force wish to express appreciation for this opportunity to serve.
The views and recommendations contained in this Final Report relate solely to measures for
future stewardship of the South Fork Rivanna Reservoir in light of the Community’s decision to
expand the Ragged Mountain Reservoir rather than the South Fork Rivanna Reservoir. We who
have served on this Task Force hope that the recommendations contained herein will bring
renewed focus upon the Reservoir and the need for Community stewardship.

Respectfully submitted,

Chair, The South Fork Rivanna Reservoir


Stewardship Task Force

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