Section 319
NONPOINT SOORCE PROGRAM SUCCESS STORY
Implementing Best Management Practices Reduces Turbidity
Watprhnrlv Imnrnvpd Little Wewoka Creek was impaired for turbidity due in part
"' to practices associated with wheat and cattle production,
prompting Oklahoma to add the creek to the state's 1998 Clean Water Act (CWA) section
303(d) list of impaired waters. Educating landowners and implementing best management
practices (BMPs) to improve pasture and nutrient management led to decreased sediment
in the creek. As a result. Little Wewoka Creek was removed from Oklahoma's 2006 CWA
section 303(d) list for turbidity impairment.
Problem
The 20-mile-long Little Wewoka Creek flows
through Seminole, Okfuskee and Hughes counties
in central Oklahoma (Figures 1 and 2). The major-
ity of the land in the area is used for cattle and
hog production, along with some wheat farming.
Erosion of poorly maintained pasture areas contrib-
uted large amounts of sediment to Little Wewoka
Creek.
In the 1998 and 2002 water quality assessments,
monitoring showed that 25 percent of Little
Wewoka Creek's seasonal baseflow water sam-
ples exceeded 50 nephelometric turbidity units
(NTU). A stream is considered impaired by turbid-
ity if 10 percent or more of the seasonal base flow
water samples exceed 50 NTU (based on 5 years
of data before the assessment year). On the basis
of the assessment results, Oklahoma added the
entire length of Wewoka Creek (20 miles) to the
1998 and subsequent CWA section 303(d) lists for
nonattainment of the fish and wildlife propagation
designated use due to suspended solids/turbidity
impairment.
Project Highlights
Landowners implemented numerous BMPs with
support from Oklahoma's locally led cost-share
program and funds from a Natural Resources
Conservation Service (NRCS) Environmental Quality
Incentives Program Local Emphasis Area project.
The primary goal of the project was to improve
grazing land quality. From 2002 to 2006, landown-
ers planted supplemental pasture grasses and hay
on 300 acres, managed brush on 34 acres, and
managed pests (weeds) on 1,900 acres. In addi-
tion, to further improve pasture and range quality
in the watershed, the landowners implemented
Little Wewoka Creek Watershed
Figure 1. The Wewoka Creek watershed is in central Oklahoma.
Figure 2. The upper reaches of Little Wewoka Creek run
through forested areas.
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prescribed grazing on 3,673 acres, nutrient manage-
ment on 1,337 acres, conservation crop rotations
on 160 acres, and forage harvest management
practices on 594 acres. Other BMPs consisted of
installing 8 acres of heavy-use-area protection to
reduce erosion from cattle activity around feeding
and watering areas, adding one grade-stabilization
structure that reduced gully erosion, and construct-
ing eight ponds.
Landowners installed additional BMPs from 2007
to 2009 that have enhanced the initial grazing land
improvements. BMPs included planting 95 acres of
critical areas, adding 10,665 linear feet of cross-
fencing, and installing several additional alternative
watering sources and protected heavy-use areas.
Other continuing and expanding BMPs include
adopting brush and weed management plans for
approximately 1,500 acres and nutrient and grazing
management plans for more than 5,000 acres.
Results
The Oklahoma Conservation Commission's (OCC's)
Rotating Basin Monitoring Program, a statewide
nonpoint source ambient monitoring program,
documented improved water quality in Little
Wewoka Creek due to landowners implement-
ing BMPs. In the 2006 water quality assessment,
monitoring showed that turbidity levels in Little
Wewoka Creek did not exceed the 50 NTU state
standard (Figure 3). Therefore, Little Wewoka Creek
now partially attains its fish and wildlife propagation
designated use, prompting Oklahoma to remove the
20-mile segment of Little Wewoka Creek from the
2006 CWA section 303(d) list for turbidity.
Since 2006 turbidity in the stream has remained low
thanks to stakeholders' continued implementation
of new BMPs and maintaining existing BMPs. Tours
and field days showcasing implemented practices
in the watershed continue to increase producer
awareness and improve grazing land management
skills, enhancing the decrease in sedimentation and
nutrients in area streams overall.
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Little Wewoka Creek
25% exceedance 0% exceedance
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2002 2006
Assessment Period
Figure 3. Turbidity in Little Wewoka Creek has declined. The
creek now meets the turbidity water quality standard, which
requires that less than 10 percent of the samples exceed
50NTU.
Partners and Funding
The Rotating Basin Monitoring Program, which
now includes a probabilistic component, is funded
through the U.S. Environmental Protection Agency's
(EPA's) CWA section 319 funds at an average annual
cost of $1 million. Monitoring costs fund personnel,
supplies and lab analysis for 19 parameters from
samples collected every 5 weeks at about 100 sites.
In-stream habitat, fish and macroinvertebrate sam-
ples are also collected. Approximately $600,000 in
EPA section 319 funds supports statewide educa-
tion, outreach and monitoring efforts through the
BlueThumb program.
The Oklahoma cost-share program provided $7,463
in state funding for BMPs in the watershed, and
landowners contributed $8,514. The NRCS invested
approximately $355,645 for implementing BMPs in
the area from 2002 to 2006. Funding for the project
has continued, with an additional $537,825 in prac-
tices installed from 2007 to 2009.
I
55
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-10-001G
March 2010
For additional information contact:
Shanon Phillips
Water Quality Division
Oklahoma Conservation Commission
shanon.phillips@conservation.ok.gov
405-522-4500
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