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Improving Pesticide Use Helps to Restore Coon, Deer, and low Creeks

% a , i i	|	, Runoff from urban and agricultural areas contributed to high levels

Waterbody Improved r	.*	^

of pesticides (chlorpyrifos) in Oklahoma s Coon, Deer and Willow
Creeks. As a result, the state added the three streams to Oklahoma's Clean Water Act (CWA) section
303(d) list of impaired waters in 2002. Education and outreach programs led by project partners
helped reduce improper use of pesticides. Implementing conservation practice systems (CPs) to
promote better land management decreased runoff of other pollutants to protect water quality
in the streams. As a result, Oklahoma removed the chlorpyrifos impairments from its 2018 CWA
section 303(d) list. Coon Creek now fully supports assessed beneficial uses and is no longer listed,
while Deer Creek and Willow Creek partially and fully support their warm water aquatic community
(WWAC) designated beneficial uses, respectively.

Problem

The watersheds of Coon Creek (20,075 acres), Deer
Creek (71,910 acres), and Willow Creek (15,097 acres)
surround the cities of Oklahoma City and Norman in
Canadian, Cleveland, Logan, and Oklahoma counties
in central Oklahoma (Figure 1). Land use in the Coon,
Deer and Willow creek watersheds is, respectively, 4%,
14% and 6% urban; 45%, 7% and 8% forested; 46%,
47% and 65% pasture and rangeland; and 0%, 30% and
20% cropland.

Water quality monitoring in the early to mid-1990s
determined that pesticide use in urban and agricul-
tural areas contributed to a 2002 listing of the streams
when 40%, 60%, and 100% of pesticide water column
samples collected in Coon, Deer, and Willow creeks,
respectively, were elevated above acute (0.083
micrograms per liter (|ig/L)) and chronic (0.041 |ig/L)
levels established in water quality standards (Figure 2).
A stream is considered impaired for pesticides if more
than 10% of sample concentrations measured are
above acute and chronic levels. Based on these results,
Oklahoma added Coon Creek (OK5207100010030_00,
12.47 miles), Deer Creek (620190040120_00, 12.67
miies, and Wiilow Creek (OK520610010080_00, 9.06
miies) to the CWA section 303(d) lists In 2002 for
nonattainment of the WWAC designated beneficial
uses. Although nonagricultural uses of chlorpyrifos
decreased after companies phased out residential uses
in 2000, the insecticide remains as one of the more
frequently used Insecticides for crops such as corn,
soybeans and many fresh produce crops.

Figure 1. Coon, Deer, and Willow creek watersheds.

Story Highlights

In 2000 the Oklahoma Department of Agriculture,

Food, and Forestry (ODAFF) adopted ruies to improve
pesticide usage in the state. These rules require licens-
ing, continuing education and registration of pesticides
in Oklahoma for anyone doing commercial or noncom-
mercial application. At least nine amendments have
been added to these ruies to remain responsive to
new information and trends in the industry, in general,
these rules and education programs address storage
and disposal, certification and testing, resolution of
complaints, licensing, record-keeping, application and
other requirements. In addition, ODAFF and partners

Legend

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1.20

Chlorpyrifos Pre-lmplementation

Deer o Willow

Chlorpyrifos Post-Implementation

0.00 q to

a Coon ^ Deer o Willow 	acute chronic

Figure 2. Chlorpyrifos levels before implementation.

have supported a program since 2006 that collects
and properly disposes of unused pesticides. As a result
of these programs, efficiency, timing, application and
record keeping for pesticides has been improved in the
state and resulted in fewer water quality impacts.

At least 77 watershed landowners worked with the
East Canadian, Cleveland, Logan, and Oklahoma
county conservation districts, the Natural Resources
Conservation Service (NRCS) and the Oklahoma
Conservation Commission (OCC) to implement CPs
through Oklahoma NRCS's Environmental Quality
Incentives Program (EQIP), Conservation Stewardship
Program (CStwP), and general conservation technical
assistance program, and through the OCC's Locally
Led Cost Share Program (LLCP). In 2000-2020 these
landowners received financial and technical assistance
to develop conservation plans addressing resource
concerns and improving crop and grazing land man-
agement through practices including pasture planting;
livestock watering; reduced tillage operations; and
brush, grazing, nutrient, and pest management.

Results

ODAFF and the OCC documented improved water
quality in Coon, Deer, and Willow creeks due to the
ODAFF pesticide program and installation of CPs through
pesticide monitoring completed by the Oklahoma Water
Resources Board (OWRB) and through the OCC statewide
nonpoint source Rotating Basin Ambient Monitoring
Program. Water column pesticide samples collected in
2011-2012 (base flow and high-flow conditions) were
below the detection limit of 0.01 |i/L (Figure 3). Fish
flesh analysis samples were also below detection limits
and benthic macroinvertebrate samples from Willow

Figure 3. Chlorpyrifos level after implementation.

Creek are healthy as well. Healthy benthic macroinverte-
brate communities suggest a low likelihood of pesticide
impacts. Based on this information, Oklahoma removed
the three creeks from the CWA section 303(d) list for
chlorpyrifos in 2018. Coon Creek now fully supports
assessed beneficial uses and is no longer listed. Deer
Creek and Willow Creek partially and fully support
their WWAC designated beneficial uses, respectively.

Partners and Funding

The OCC monitoring program is supported by 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 319
funds support statewide water quality educational
efforts through Blue Thumb. Approximately $485,610
of these federal and state matching funds have been
devoted to the three creeks.

The ODAFF Consumer Protection Division maintains
the Oklahoma Pesticide Applicator and Licensing
Program, which includes response to pesticide
complaints, education and certification of pesticide
applicators, and similar functions. ODAFF worked with
the OWRB to reassess these streams for pesticides
more than a decade after initial listing. From 2000 to
2020, NRCS supplied more than $100,000 for CP imple-
mentation in Oklahoma through EQIP. In addition,
many practices were funded by landowners based on
recommendations through CStwP and NRCS general
technical assistance. Finally, the OCC; Cleveland, East
Canadian, Logan, and Oklahoma county conservation
districts; and landowners funded more than $133,126
worth of CPs (at least $65,831 of which was funded by
landowners through the LLCP).

^edsj^ U.S. Environmental Protection Agency

0** Office of Water
^ Washington, DC

WJ

EPA 841-F-21-001HH
PROt^° December 2021

For additional information contact:

Shanon Phillips

Oklahoma Conservation Commission
405-522-4728 • shanon.phillips@conservation.ok.gov

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