Section 319
NONPOINT SOORCE PROGRAM SUCCESS STORY
Implementing Best Management Practices Restores Creek
Imnrnx/pH
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Little Wewoka Creek was impaired due in part to practices associated
wjth wheat and catt|e production/ prompting Oklahoma to add the
creek to the state's Clean Water Act (CWA) section 303(d) list of impaired waters for turbidity (1998) and
dissolved oxygen (2006). 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.
Water quality has continued to improve and Little Wewoka Creek has been nominated for removal from
Oklahoma's 2010 CWA section 303(d) list for dissolved oxygen impairment. This brings the stream into
full attainment of its fish and wildlife propagation designated use.
Problem
The 20-mile-long Little Wewoka Creek flows through
Seminole, Okfuskee and Hughes counties in central
Oklahoma (Figures 1 and 2). The majority of the land
in the area is used for cattle and hog production,
along with some wheat farming. Erosion of poorly
maintained pasture areas (including overstocking and
allowing brush and weed overgrowth) contributed
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 samples
exceeded 50 nephelometric turbidity units (NTU).
A stream is considered impaired by turbidity 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 nonattain-
ment of the fish and wildlife propagation designated
use due to suspended solids/turbidity impairment.
In addition, the creek has been included on
Oklahoma's CWA section 303(d) list since 2006 as
not attaining its fish and wildlife propagation use
because of low dissolved oxygen levels. In the 2006
and 2008 assessments, 15 percent of samples
fell below the critical value of 5.0 milligrams per
liter (mg/L) dissolved oxygen. A stream is consid-
ered impaired for dissolved oxygen if more than
10 percent of samples are below 5 mg/L. Runoff
of wastes and sediment from poor pasture mainte-
nance and improper management of cattle wastes
may contribute nutrients to the creek. Excess
nutrients may lead to the overgrowth of nuisance
algae, and the subsequent breakdown of the algae
may then cause dissolved oxygen levels to drop.
Little Wewoka Creek Watershed
Figure 1. The Wewoka Creek watershed is in central Oklahoma.
Figure 2. Little Wewoka Creek flows through agricultural
areas.
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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 graz-
ing land quality.
From 2002 to 2009, landowners improved pastures
through supplemental planting on 378 acres, brush
management on 48 acres, and weed management
on over 3,400 acres. In addition, 2,155 acres had
nutrient management plans and over 8,660 acres
had grazing management plans implemented.
Landowners installed 135 acres of critical area plant-
ing, 10,665 linear feet of cross-fencing, 10 acres of
heavy use area protection around feeding and water-
ing areas, one grade stabilization structure, and eight
ponds to further improve pastures and range and to
reduce erosion from cattle activity in the watershed.
Finally, conservation crop rotations were adopted
on 191 acres, in addition to 30 acres of no-till and
859 acres of forage harvest management practices.
Results
The Oklahoma Conservation Commission's Rotating
Basin Monitoring Program (RBMP), a statewide
nonpoint source ambient monitoring program, doc-
umented improved water quality in Little Wewoka
Creek due to landowners implementing BMPs. In
the 2006 water quality assessment, monitoring
showed that turbidity levels in Little Wewoka Creek
met the 50 NTU water quality standard (Figure 3).
Therefore, Oklahoma removed 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. As
a result of the practices implemented beginning in
2002, dissolved oxygen values have also improved
in the Little Wewoka Creek watershed. In the 2006
and 2008 assessments, 15 percent of the creek's
dissolved oxygen samples were below the critical
value of 5.0 mg/L. This was reduced to 0 percent
in the 2010 assessment (Figure 4). Hence, Little
Wewoka Creek has been nominated for removal
from Oklahoma's 2010 CWA section 303(d) list for
dissolved oxygen impairment and now fully attains
its fish and wildlife propagation designated use.
Tours and field days showcasing implemented
practices in the watershed increased producer
awareness and improved grazing land management
Little Wewoka Creek Turbidity Levels
25% exceedance
0% exceedance
* •«
Assessment Period
Figure 3. Little Wewoka Creek met the turbidity
water quality standard in 2006.
Little Wewoka Creek Dissolved Oxygen Levels
01
15% exceedance
0% exceedance
2006 2010
Assessment Year
Figure 4. Little Wewoka Creek met the dissolved
oxygen water quality standard in 2010.
skills, enhancing the decrease in sedimentation and
nutrients in the area streams overall.
Partners and Funding
The RBMP, which now includes a probabilistic com-
ponent, is funded through the U.S. Environmental
Protection Agency's (EPA's) CWA section 319 pro-
gram at an average annual cost of $1 million.
Monitoring costs include personnel, supplies and
lab analysis for 19 parameters from samples col-
lected every 5 weeks at about 100 sites. In-stream
habitat, fish and macroinvertebrate samples are
also collected. Approximately $600,000 in EPA
CWA section 319 funding supports statewide
education, outreach and monitoring efforts through
the Blue Thumb program. The Oklahoma cost-share
program provided $7,463 in state funding for BMPs
in the watershed (channeled through the conserva-
tion districts in Seminole, Okfuskee and Hughes
counties), and landowners contributed $8,514. The
NRCS invested approximately $893,470 for imple-
menting BMPs in the area from 2002 to 2009.
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-11-001V
March 2011
For additional information contact:
Shanon Phillips
Water Quality Division
Oklahoma Conservation Commission
shanon.phillips@conservation.ok.gov
405-522-4500
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