Section 319
NONPOINT SOURCE PROGRAM SOCGESS STORY
Installing Best Management Practices Improves Dissolved Oxygen Levels
in Oklahoma's Stinking Creek
Waterbodv Improved Low dissolved oxY9en (D°). attributed in part to practices
"J '"' ' ''"' • - associated with wheat and cattle production, resulted in
impairment of Stinking Creek. As a result, Oklahoma placed the creek on the state's Clean
Water Act (CWA) section 303(d) list in 2008. Implementing best management practices
(BMPs) improved the quality of cropland and grazing lands, thereby decreasing sediment
and nutrient runoff into the creek. DO levels improved, prompting Oklahoma to recommend
that Stinking Creek be removed from the state's 2012 CWA section 303(d) list for low DO.
Problem
Stinking Creek (Figure 1) flows for more than
12 miles through central Oklahoma's Caddo County,
an area with high rates of wheat and cattle produc-
tion. Poor management of cropland and grazing
lands contributed to excess sedimentation and
nutrient runoff in the watershed. Excess nutrients
can lead to the overgrowth of nuisance algae, and
the subsequent breakdown of the algae can then
cause DO levels to decline. Water quality assess-
ments conducted between 2006 and 2008 showed
that the amount of DO was continuing to drop, with
43 percent of the water samples included in the
2008 assessment below (i.e., not meeting) state
criteria for warm-water aquatic communities. A
waterbody is considered impaired for DO if more
than 10 percent of samples (based on no more than
5 years of data before the assessment year) fall
below 6.0 milligrams per liter (mg/L) from April 1
through June 15 or below 5.0 mg/L during the
remainder of the year. On the basis of these assess-
ment results, Oklahoma added Stinking Creek to the
2008 and subsequent CWA section 303(d) lists for
failing to support the fish and wildlife propagation
designated use due to DO impairment.
Project Highlights
Landowners implemented BMPs with assis-
tance from Oklahoma's locally led cost-share
program and through the local Natural Resources
Conservation Service (NRCS) Environmental
Quality Incentives Program and general technical
assistance program. These projects focused on
Figure 1. Stinking Creek is in central Oklahoma.
reducing erosion by improving cropland and graz-
ing lands. From 2006 to 2012, landowners imple-
mented no-till, strip-till or direct-seed practices on
210 acres. In contrast to traditional tillage, these
"conservation tillage" methods retain soil moisture
and reduce soil erosion by decreasing the amount
of soil exposed to wind and rain. Landowners
installed 1,150 feet of diversions, three grade
stabilization structures, three acres of grassed
waterways, and 12 acres of critical area planting,
which further reduced erosion potential on crop-
land. Landowners also adopted integrated pest
management practices on 1,767 acres. To improve
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the condition of pasture and rangeland, prescribed
grazing was implemented on 1,484 acres, and
2,045 acres received nutrient management plans.
Producers installed four new ponds, one water
well, and 400 feet of pipeline to provide livestock
with alternative water supplies to keep them out
of the creek. Agricultural producers also planted
forage on 625 acres.
In addition, the Oklahoma Conservation
Commission's (OCC) education program, Blue
Thumb, actively promoted restoration efforts in the
Stinking Creek watershed in conjunction with the
nearby Fort Cobb and Sugar Creek watersheds.
Several volunteer training events were held. These
activities provided vital education of the residents
of the watershed and helped facilitate behavior
changes. Active volunteer monitoring and education
efforts continue in the area.
Results
The OCC's Rotating Basin Monitoring Program,
a statewide nonpoint source ambient monitoring
program, documented improved water qual-
ity in Stinking Creek after restoration efforts.
Implementing practices and educating landown-
ers helped reduce nutrients entering the stream,
which in turn allowed DO levels to improve
because algae were less likely to be overgrown
and die off.
To meet state DO criteria for warm-water aquatic
communities, Stinking Creek samples may not fall
below critical DO levels (5.0 or 6.0 mg/L, depend-
ing on the season) more than 10 percent of the
time. Monitoring data showed that 43 percent of
samples from the 2008 assessment fell below
the critical DO levels and failed to meet state DO
criteria. During the 2012 assessment, only eight
percent of samples fell below the critical DO
level, which met the state DO criteria (Figure 2).
As a result, Oklahoma has recommended Stinking
Creek for removal from the state's 2012 CWA sec-
tion 303(d) list for dissolved oxygen impairment.
Stinking Creek
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2006
2012
2008
Assessment Year
* Meets DO criteria (No more than 10 percent of samples fall below critical DO levels)
Figure 2. Data show that DO levels in Stinking Creek met state
criteria for warm-water aquatic communities in 2012.
Partners and Funding
The Rotating Basin Monitoring Program, which
includes both fixed and probabilistic compo-
nents, is funded through the U.S. Environmental
Protection Agency's (EPA) CWA section 319 funds
at an average annual cost of $1 million. Monitoring
costs include personnel, supplies and lab analysis
for 19 parameters from samples collected every
five weeks at about 100 sites. In-stream habitat,
fish and macroinvertebrate samples are also col-
lected. Approximately $600,000 in EPA section
319 funds support statewide education, outreach
and monitoring efforts through the Blue Thumb
program. Over the past decade, the Oklahoma
cost-share program has provided $11,548 in
state funding for BMPs in this watershed through
the South Caddo Conservation District. NRCS
has spent approximately $93,500 to implement
BMPs in the watershed from 2006 through
2012. Additionally, landowners have provided a
significant percentage of the cost, usually 40 to
60 percent, toward BMP implementation.
UJ
(9
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-12-001X
August 2012
For additional information contact:
Shanon Phillips, Director
Water Quality Division
Oklahoma Conservation Commission
shanon.phillips@conservation.ok.gov
405-522-4500
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