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1 NONPOINT SOURCE SUCCESS STURY
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Mineral Bayou Waters Run Clearer With Conservation Practice
Installations
Waterbody Improved
High turbidity levels resulted in impairment of Mineral Bayou
Creek and placement on Oklahoma's Clean Water Act (CWA)
section 303(d) list of impaired waters in 2012. Pollution from cropland, grazing lands and urban
areas contributed to this impairment. Implementing conservation practice systems (CPs) to promote
better land management in agricultural areas decreased pollutant runoff and turbidity levels in the
stream. As a result, Oklahoma removed the turbidity impairment from its 2014 CWA section 303(d)
list. Mineral Bayou Creek now fully supports its warm water aquatic community (WWAC) designated
beneficial use.
Problem
The Mineral Bayou watershed covers approximately
25,120 acres in Bryan County, Oklahoma (Figure 1).
Land use in the watershed is about 71 percent man-
aged pasture land. Approximately 16 percent of the
watershed is developed, which includes the town of
Durant, Oklahoma. Durant is a rapidly growing com-
munity along Oklahoma's southern border and is the
capital city and headquarters of the Choctaw Nation.
The primary agricultural products from the watershed
are hay and cattle.
Water quality monitoring in the mid-2000s determined
that challenges with grazing land management
contributed to a 2012 listing of a 15.53-mile segment
of the stream as impaired by turbidity, when at least
12 percent of turbidity readings exceeded acceptable
imits. A stream is considered impaired for turbidity if
more than 10 percent of baseflow samples exceed 50
nephelometric turbidity units (NTU) during an assess-
ment period. Based on these results, Oklahoma added
segment OK410600010300_00 to the CWA section
303(d) lists in 2012 for nonattainment of the WWAC
designated beneficial use.
Story Highlights
At ieast 20 landowners in the watershed worked with
the Bryan County Conservation District, the Oklahoma
Conservation Commission (OCC) and the Natural
Figure 1. The Mineral Bayou watershed is in southern Oklahoma.
Resources Conservation Service (NRCS) to implement
CPs through the OCC's Locally Led Cost Share Program
(LLCP) and through Oklahoma NRCS's Environmental
Quality Incentives Program (EQIP), Conservation
Stewardship Program (CSP) and general conservation
technical assistance program.
From 2005 to 2018, landowners improved grazing
management, which reduced runoff of sediment and
other pollutants by increasing vegetative cover and
reducing bare soil.
Landowners implemented access control (136 acres
[ac]), brush management (57 ac), conservation cover
(136 ac), critical area planting (1 ac), fence (7,503 feet),
Legend
Monitoring Sites
~ Mineral Bayou Watershed

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grade stabilization structures (1), nutrient manage-
ment (279 ac), pasture and hayland planting (257 ac),
pest management (249 ac), ponds (11), pond cleanout
(1), prescribed grazing (575 ac), split nitrogen applica-
tions (43 ac), and tree and shrub planting (1 ac).
Results
The OCC documented improved water quality in
Mineral Bayou Creek due to installation of CPs through
its statewide nonpoint source Rotating Basin Ambient
Monitoring Program. By 2014, turbidity exceedances
had dropped to 6 percent and remained at similar
levels through the 2020 assessment period (Figure 2).
Based on these data, Oklahoma removed Mineral
Bayou Creek from the CWA section 303(d) list for DO
in 2014. Mineral Bayou Creek now fully supports its
WWAC beneficial use.
Partners and Funding
The OCC monitoring program is supported by the
U.S. Environmental Protection Agency's (EPA's) CWA
section 319 funding at an average annual statewide
cost of $1 million. Approximately $500,000 in EPA sec-
tion 319 funds support statewide water quality edu-
cational efforts through Blue Thumb. Approximately
$217,400 of these federal and state matching funds
have been devoted to Mineral Bayou Creek. From
2005 to 2018, NRCS supplied more than $20,000 for
CP implementation in Oklahoma through EQIP. In addi-
tion, many practices were funded through CSP and by
landowners based on recommendations through NRCS
general technical assistance. Finally, the OCC, Bryan
County Conservation District, and landowners funded
more than $20,524 worth of CPs (at least $10,199 of
which was funded by landowners through the LLCP).
exceedance:
12%
Mineral Bayou Turbidity
6%
0%
'gure 2. Turbidity decreased in Mineral Bayou Creek with the installation of CPs.
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U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA EPA 841-F-20-001QQ
December 2020
For additional information contact:
Shanon Phillips
Oklahoma Conservation Commission
405-522-4728 • shanon.phillips@conservation.ok.gov

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