Section 319
NONPOINT SOURCE PROGRAM SUCCESS STOSY
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Riparian Area Grazing Management Practices Reduce Phosphorus Loads
and Restore Water Quality
WatPrhnHv I mnrnvpH Excess phosphorus from agricultural runoff led Utah to list the upper
""' " " '" and lower segments of the Little Bear River on its 1998, 2000 and
2002 303(d) lists of impaired waterbodies. Landowners, local watershed organizations and many
federal, state and local government agencies collaborated to implement agricultural best manage-
ment practices (BMPs), which improved water quality in the Little Bear River and its tributaries. These
improvements prompted the Utah Department of Environmental Quality (UDEQ) to remove the upper
segment of the Little Bear River from the 303(d) list for total phosphorus (TP) in 2004. Water quality in
the lower segment of the Little Bear River has also improved significantly, but it still exceeds standards
and remains on the 2004 303(d) list for TP and hydrological modification.
Problem
The Little Bear River is split into upper and lower
segments for management purposes. The upper
segment is approximately 6.8 miles long and runs
from the East Fork to Hyrum Reservoir. The lower,
28.1-mile segment runs from Hyrum Reservoir to
Cutler Reservoir. UDEQ included both segments
on its 1998, 2000 and 2002 303(d) lists of impaired
waterbodies because the segments did not fully
support aquatic life and cold water fishery des-
ignated uses due to high TP concentrations and
hydromodification.
Agricultural practices are the leading sources of the
nonpoint source pollution in the Little Bear River
and the primary cause of water quality impairment.
Much of the corridor is used for livestock grazing
and crop production. In addition, several tributar-
ies contributed high sediment loads during storm
events—largely because of severe streambank
erosion, channel straightening, road damage, poorly
managed upland grazing and cropland erosion
(Figure 1).
The Little Bear River total maximum daily load
(TMDL) outlines several goals, including that TP
concentrations may not exceed the water quality
standard, 0.05 milligrams per liter (mg/L), and that
theTP load will be reduced by 13 kilograms per
day (kg/day) above Cutler Reservoir and 2.4 kg/day
above Hyrum Reservoir. Although the goal is to
not exceed the TP standard at all, a stream is not
actually identified as nonsupporting until 25 percent
or more of its samples exceed the 0.05 mg/L TP
value. Therefore, to meet water quality standards,
the TP levels in Little Bear River must not exceed
Figure 1. This photo shows an example of a typical
eroding streambank in the Little Bear River water-
shed before the restoration project began.
the 0.05 mg/L standard more than 25 percent
of the time. The TMDL also identifies hydrologic
modification as a water quality concern in the lower
segment. Phosphorus is readily adsorbed to sedi-
ment particles, so a reduction in erosion and total
suspended solids will also lead to a reduction in TP
in both segments.
Project Highlights
Beginning in 1989, community planning efforts by
the Little Bear River Steering Committee gave rise
to the operating structure of this project, and over
the course of 15 years, the public has been continu-
ously informed and involved. The group developed
the Little Bear River Watershed Plan in 1992 as
part of a comprehensive, coordinated resource
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management effort to address nonpoint source
pollution in the drainage basin.
Since then, project partners implemented more
than 100 water quality improvement projects on the
Little Bear River and its tributaries, including many
different types of riparian area grazing manage-
ment and streambank stabilization BMPs. These
included stabilizing 9,350 feet of streambank using
14 in-channel drop structures and 19 rock barbs,
completing 59 animal waste management projects,
placing more than 22,300 feet of riparian fencing
and implementing many other projects such as filter
strips, livestock exclusion, pasture planting, range
seeding and other farming and irrigation BMPs.
Project partners also established successful educa-
tion and outreach programs and completed several
fishery improvement projects.
Results
The cumulative effects of these on-the-ground
restoration efforts, combined with outreach and
education activities, have led to better land use
practices by landowners and reduced pollutant
loadings to the streams (Figure 2). Data show that
water quality in both segments of the Little Bear
River has significantly improved. Figure 3 presents
the percentage of samples exceeding the TP stan-
dard during three periods of intensive monitoring
conducted since 1993. TheTP levels in the upper
segment decreased from 34 percent exceedance
of the standard in the 1993-1994 monitoring cycle
to 8 percent exceedance by the 2003-2004 cycle.
The TP levels in the lower segment decreased
from 88 percent exceedance of the standard in the
Figure 2. This photo shows an example of a restored
stream channel in the Little Bear River watershed
after significant restoration had taken place.
1993-1994 cycle to 50 percent exceedance by the
2003-2004 cycle.
These results indicate that TP levels in the upper seg-
ment of the Little Bear River are consistently below
state water quality standards. Therefore, UDEQ
removed the upper 6.8 miles of the Little Bear River
from its 2004 303(d) list for TP. Although the lower
segment is still nonsupporting, a steady decrease
in TP and total suspended solids indicates that the
BMPs in place are positively affecting the watershed.
Percent Exceedances of TP for Upper and Lower Sections
of the Little Bear River
Upper
Lower
Figure 3. Recent monitoring data show that TP
levels in the upper section of the Little Bear River
are now below the 25 percent exceedance target
level as represented by the red dotted line.
Partners and Funding
Since 1991 UDEQ has administered a total of
$1,616,055 in Clean Water Act section 319 grant
funds to implement the variety of BMPs previously
mentioned. Project partners relied on an additional
$1,082,170 of nonfederal and $1,554,178 in federal
funding to restore the Little Bear River watershed.
Utah Division of Wildlife Resources and Utah
State University conducted specific partnership
efforts to improve the fishery and fish habitat. U.S.
Department of Agriculture funds helped improve
habitat and agricultural production by focusing
on a holistic approach to farm and environmental
management. The Natural Resources Conservation
Service provided technical assistance to plan,
design, implement BMPs and evaluate BMP effec-
tiveness. U.S. Fish and Wildlife Service provided
technical assistance for fish habitat projects and
streambank and stream channel design. Local
participants included the Cache County Local Work
Group, the local soil conservation district, the Little
Bear Water Users Association, Cache Society of
Fisheries and many others.
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-08-001G
June 2008
For additional information contact:
Mike Allred, Utah Department of
Environmental Quality
801-538-6316 • mdallred@utah.gov
Gary Kleeman, EPA Region 8
303-312-6246 • kleeman.gary@epa.gov
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