![[logo] US EPA](http://www.epa.gov/epafiles/images/logo_epaseal.gif){kind=logo}
Oklahoma: Little Wewoka Creek
Implementing Best Management Practices Reduces Turbidity
Waterbody | Problem | Project Highlights | Results | Partners & Funding
Waterbody Improved
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.
Contact:
Shanon Phillips
(shanon.phillips@conservation.ok.gov)
Water Quality Division
Oklahoma Conservation
Commission
405-522-4500
Figure 1. The Wewoka Creek watershed is in central Oklahoma.
Figure 2. The upper reaches of Little Wewoka Creek run through forested areas.
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 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 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, landowners planted supplemental pasture grasses and hay on 300 acres, managed brush on 34 acres, and managed pests (weeds) on 1,900 acres. In addition, to further improve pasture and range quality in the watershed, the landowners implemented prescribed grazing on 3,673 acres, nutrient management 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 constructing 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 implementing 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.
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 samples are also collected. Approximately $600,000 in EPA section 319 funds 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, 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 practices installed from 2007 to 2009.
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 50 NTU.