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NONPOINT SOURCE SUCCESS STORY
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Conservation Practices Increase Oxygen Concentrations in Finn Creek
Waterbody improved
Low dissolved oxygen (DO) levels resulted in impairment of Finn
Creek and placement on Oklahoma's Clean Water Act (CWA)
section 303(d) list of impaired waters in 2008. Pollution from cropland and grazing lands contributed
to this impairment. Implementing conservation practice systems (CPs) to promote better land
management decreased pollutant runoff and increased oxygen levels in the stream. As a result,
Oklahoma removed the DO impairment in 2016 from its CWA section 303(d) list. Finn Creek now
fully supports its warm water aquatic community (WWAC) designated beneficial use.
Problem
The Finn Creek watershed covers approximately 42,420
acres in Garvin and McLain counties in Oklahoma
(Figure 1). Land use in the watershed is about 77
percent managed pasture and cropland, the majority
of which is pasture land. Most of the cultivated fields
lie in the flat iands along the stream. Approximately
15 percent of the watershed is rangeland. The primary
agricultural products from the watershed are wheat,
soybeans, hay and cattle.
Water quality monitoring in the mid-2000s deter-
mined that challenges with grazing land and cropland
management contributed to a 2008 listing of a
14.15-mile segment of the stream as impaired by
DO, when at least 15 percent of readings exceeded
acceptable limits. A stream is considered impaired for
DO if more than 10 percent of samples fall below 6.0
milligrams per liter (mg/L) from April 1 through June
15 or fall below 5.0 mg/L (with allowances for a 1 mg/L
excursion for one hour per day) during the remainder
of the year. Based on these results, Oklahoma added
segment OK310810020020_00 to the CWA section
303(d) list in 2008 for nonattainmerit of the WWAC
designated beneficial use.
Legend
Monitoring Sites
Finn Creek WS Streams
Finn Creek
County Boundaries
~ Finn Creek Watershed
Story Highlights
More than 50 landowners in the watershed worked
with the Garvin and McClain county conservation
districts, the Oklahoma Conservation Commission
(OCC) and the Natural Resources Conservation Service
(NRCS) to implement CPs through the OCC's Locally
Led Cost Share Program (LLCP) and Oklahoma NRCS's
Figure 1. The Finn Creek watershed is in southern Oklahoma.
Environmental Quality Incentives Program (EQIP) and
general conservation technical assistance program.
From 2007 to 2018, landowners improved croplands
and grazing management, which reduced runoff of
sediment and other pollutants by increasing vegetative
cover and reducing bare soil.
Landowners implemented access control (25 acres
[ac]), brush management (489 ac), conservation cover
(1,330 ac), conservation crop rotation (1,795 ac),
contour farming (75 ac), cover crop (2,298 ac), critical
area planting (24 ac), diversion (4,518 feet [ft]), fence
(31,968 ft), forage harvest management (595 ac),
firebreak (37,705 ft), grade stabilization structures (12),
grassed waterways (4.3 ac), heavy use protection areas
(0.3 ac), herbaceous weed treatment (622 ac), nutrient
management (7,428 ac), pasture and hayland planting
(7,982 ac), pest management (5,497 ac), ponds (15),

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prescribed burning (264 ac), prescribed grazing (5,832
ac), no-till (800 ac), reduced tillage (2,498 ac), seasonal
residue management (79 ac), terraces (2,8374 ft), tree
planting (85 ac), upland wildlife habitat management
(181 ac), water wells (4) and watering facilities (1).
Results
The OCC documented improved water quality in Finn
Creek due to installation of CPs through Its statewide
nonpoint source Rotating Basin Ambient Monitoring
Program. By 2016, DO exceedances had dropped to
5 percent and remained at similar levels through the
2020 assessment period (Figure 2). Based on these
data, Oklahoma removed Finn Creek from the CWA
section 303(d) list for DO in 2016. Finn 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
$249,870 of these federal and state matching funds
have been devoted to Finn Creek. From 2008 to 2018,
NRCS supplied more than $574,000 for CP imple-
mentation in Oklahoma through EQIP. In addition,
many practices were funded by landowners based on
recommendations through NRCS general technical
assistance. Finally, the OCC, Garvin and McClain county
conservation districts, and landowners funded more
than $55,193 worth of CPs (at least $37,553 of which
was funded by landowners through the LLCP).
Finn Creek Dissolved Oxygen
2003 2010
2012
2014 2016
2018
2020
Figure 2. DO in Finn Creek improved with the installation of CPs.
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U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA 841-F-20-001SS
December 2020
For additional information contact:
Shanon Phillips
Oklahoma Conservation Commission
405-522-4728 • shanon.phillips@conservation.ok.gov

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