Section 319
NONPOINT SOURCF PKAM SUGGESf STORY
Reservoir Restoration and Watershed Treatment Efforts Improve Water Quality
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Urban and construction site runoff carried phosphorus, sediment and asso-
ciated pollutants to Nebraska's Holmes Lake. These pollutant loadings cre-
ated eutrophic conditions characterized by turbid water, high nutrients, low
dissolved oxygen, excessive algae growth and shallow water depths. Nebraska Department of Environmental
Quality (NDEQ) added the lake to the state's 1998 Clean Water Act section 303(d) list because of aquatic life
use impairments. In 2000 the city of Lincoln initiated a Community Based Planning process, with the goal of
developing a locally led Lake and Watershed Management Plan that would address water quality issues. The
primary components of the plan included watershed treatment, extensive education and lake rehabilitation. The
project was a success, and water quality improved. As a result, NDEQ first removed dissolved oxygen from the
list of impairments in 2002 and then removed sedimentation and nutrients from the list of impairments in 2008.
Holmes Lake now fully supports all its assigned beneficial uses.
Problem
Holmes Lake is in southeastern Nebraska in
Lincoln and falls within the Lower Platte River
Basin. The U.S. Army Corp of Engineers com-
pleted the construction of the 123-acre lake
in 1962. It serves as a recreational resource
for local citizens and is managed by Lincoln's
Department of Parks and Recreation. NDEQ
added the lake to the state's 1998 Section
303(d) impaired waters list for atrazine, arsenic,
nutrients, dissolved oxygen and sedimentation.
Nebraska revised its surface water quality stan-
dards for atrazine and arsenic in 1999. Because
of the changes, atrazine and arsenic levels in
Holmes Lake no longer violated standards, and
NDEQ removed these two pollutants from the
2000 303(d) list for Holmes Lake.
Data collected between 1995 and 1998 show
that average concentrations of dissolved
oxygen in the water column fell below the
water quality standard of 5.0 milligrams per
liter (mg/L) for 5 of the 21 surface-to-bottom
profiles. Nutrient listings are partially based
on growing season mean chlorophyll a con-
centrations exceeding 44 milligrams per cubic
meter (mg/m3). The pre-project (1976-2001)
chlorophyll a growing season average value
was 46.52 mg/m3. NDEQ added sedimentation
to the list of pollutants because of the violation
of two assessment criteria. The first criterion
is the annual sedimentation rate. From 1984 to
1993, the average annual loss of original lake
Figure 1. Pre-project
condition of a stream
draining to Holmes
Lake. Severe stream-
bank erosion contrib-
uted sediment and
nutrients to Holmes
Lake.
volume was 1.31 percent, which exceeded the
criteria of 0.75 percent. The second criterion is
the total lake volume lost. As of 1993, Holmes
Lake had lost 27 percent of the original volume,
which exceeded the 25 percent total volume
loss criterion (Figure 1).
NDEQ developed a total maximum daily load
(TMDL) for sediment and phosphorus in 2003.
The TMDL identified annual loading reductions
of 53 percent for sediment and 97 percent for
phosphorus to achieve a full-support status in
the lake.
Project Highlights
The Community Based Planning process
encouraged extensive public input. Through
this process, various community members
representing lake users, educators and
watershed residents came together to form a
Watershed Advisory Committee (WAC). The
WAC drove the development of project goals,
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objectives and specific action items. While
the lake restoration was completed in 2005,
watershed treatment and educational activities
are ongoing. Since watershed build-out was
nearly completed in the 1990s, on-the-ground
controls were limited to rain gardens (20),
wetland development (10 acres), and drainage
network stabilization (Figure 2). Primary in-lake
efforts included removing 321,000 cubic yards
of sediment, stabilizating 2.4 miles of shoreline
and restoring fish habitat.
The WAC implemented an extensive educational
program that continues today. While educational
efforts cover a broad range of issues, the focus
is on lawn fertilizers and pet waste. According
to surveys conducted in the watershed, approxi-
mately 63 percent of the homeowners now
use either low phosphorus or non-phosphorus
fertilizer. During the course of the project, the
Lincoln-Lancaster County Health Department
and city of Lincoln worked together to adopt a
citywide pet waste ordinance.
Results
Of the nine water quality profiles measured
from 1999 through 2001, no violations of
the state's dissolved oxygen standard were
observed (Figure 3). As a result, NDEQ
removed dissolved oxygen from
the state's 2002 303(d) of impaired
waters. Post-project (2006-2007)
chlorophyll a values of 17.30 mg/m3
met standards and prompted NDEQ
to remove the chlorophyll a impair-
ment from the 2008 303(d) list.
Sedimentation also declined. The
average annual lake volume loss fell
to 0.13 percent, and sediment removal
efforts in the lake reduced the loss
of original volume to 14 percent.
Consequently, NDEQ removed the
sedimentation impairment from the
state's 303(d) list in 2008. As a result
of the in-lake and watershed improve-
ments, Holmes Lake now fully sup-
ports all beneficial uses.
Figure 2. Post-project
condition of a stream
draining to Holmes
Lake. The revegetat-
ed stream channel
includes rock piles
that serve as check
dams to slow water
flow to the lake.
Partners and Funding
The project was made possible through a
strong partnership between Lincoln, Nebraska
Environmental Trust, Nebraska Game and
Parks Commission, Lincoln-Lancaster County
Health Department, EPA, NDEQ and the
Holmes Lake Watershed Council. Section
319 funding supported water quality planning
and demonstrations ($95,119), information
and education ($34,934), sediment removal
($2,084,409), engineering design ($311,588)
and drainage network rehabilitation ($163,616).
Additional sources of project funding include
the city of Lincoln ($1,275,099), Nebraska
Game and Parks Commission ($1,777,000),
Nebraska Environmental Trust ($620,000) and
the Lower Platte South Natural Resources
District ($67,483).
Holmes Lake: Water Column Average Dissolved Oxygen
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1 = Assessment Criteria Vio ation
1998 303(d) Listing 2002 303(d) De-listing
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Wetland Construction: 1996 & 2000
Lake Restoration/Watershed Treatment/Education: 2001-present
Figure 3. Bar graph noting water column average dissolved oxygen measure-
ments by sampling date. Red bars indicate a violation of assessment criteria.
Data show no violations since 1998.
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U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-08-001AA
September 2008
For additional information contact:
Paul Brakhage
Nebraska Department of Environmental Quality
Water Quality Assessment Section
402-471-4224 • paul.brakhage@nebraska.gov
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