NONPOINT SOURCE SUCCESS STORY
Implementing Agricultural Best Management Practices Restores Aquatic
Life Uses in a Segment of North Fork Crazy Woman Creek
Waterbody Improved
Livestock grazing and irrigation practices dating back to the 1880s
contributed to high sediment and nutrient loads that degraded
biological conditions in Wyoming's North Fork Crazy Woman Creek (NFCWC). As a result, in 1996
the Wyoming Department of Environmental Quality (WDEQ) added a segment of NFCWC to the
state's Clean Water Act (CWA) section 303(d) list of impaired and threatened waters for threats to
aquatic life uses due to habitat degradation (sediment) and nutrient enrichment. The Lake DeSmet
Conservation District (LDCD) led watershed restoration efforts and worked with private landowners
to implement agricultural best management practices (BMPs). Recent monitoring indicates that
aquatic life uses are now supported. WDEQ anticipates this segment of NFCWC will be removed
from the 2014 CWA section 303(d) list of impaired waters.
Problem
NFCWC originates at an approximate elevation of
8,800 feet in the Big Horn Mountains and flows
southeast to its confluence with the Middle and
South Forks of Crazy Woman Creek near the town
of Buffalo, Wyoming (Figure 1). Designated uses for
NFCWC include drinking water, cold water fisheries,
fish consumption, nongame fisheries, aquatic life oth-
er than fish, recreation, wildlife, agriculture, industry
and scenic value. Major land uses in the watershed
include irrigated and nonirrigated cropland, livestock
grazing and logging operations.
In the early 1990s, LDCD personnel indicated that
significant watershed degradation had occurred
since the area was homesteaded in the 1880s.
Intense rangeland livestock grazing, concentration
of livestock in riparian areas, and inefficient irriga-
tion systems had resulted in water loss, erosion,
and subsequent sediment and nutrient loading to
NFCWC. This degradation resulted in deterioration
of the NFCWC fishery, which, according to Wyoming
Game and Fish Department (WGFD), was originally
classified as a trout fishery of regional importance.
High water temperatures, low flows related to stream
diversion, limited productivity due to turbidity, and
limited salmonid reproduction due to lack of suitable
substrate were problems identified by WGFD.
Baseline chemical, physical and biological monitor-
ing was conducted by WDEQ in 1991 and 1992. Data
indicated a general trend of decreasing water quality
North Fork Crazy Woman Creek, Wyoming
Middle North Fork Crazy Woman Creek
HUC12
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Upper North Fork Crazy Woman CreekJ
I
Figure 1. The North Fork Crazy Woman Creek watershed is in
northern Wyoming.
in a downstream direction when transitioning from
the mostly forested mountains/foothills of the upper
watershed to areas of high agricultural development
in the plains of the lower watershed. Nutrients, as
evidenced by the relative occurrence of periphyton
and filamentous algae, increased from foothills loca-
tions to plains locations, as did conductivity levels,
while habitat assessment scores decreased. The
shift from a fish community dominated by trout at
foothills locations to a fish community dominated by
suckers and other nongame species at lower plains
locations further indicated that water quality and
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Results
Figure 2. A staff member collects water quality data at a
riffle monitoring site on North Fork Crazy Woman Creek.
habitat degraded with distance downstream. WDEQ
placed a 28-mile segment of NFCWC (segment
WYPR100902050100_01)onthe 1996 CWA section
303(d) list of impaired and threatened waters due to
threats to aquatic life uses from habitat degradation
and nutrient enrichment.
Project Highlights
LDCD and landowners proactively initiated restora-
tion efforts on private lands in the watershed. In
1990 LDCD was awarded CWA section 319 funding
to improve the cold water fishery, restore degraded
riparian areas and reduce sediment and nutrient
loading to the creek. BMPs to achieve these goals
were implemented between 1992 and 1996. Critical
areas were stabilized through a re-seeding project
to mitigate erosion, and over 1 mile of riparian fence
was installed to protect the sensitive riparian zone
from livestock grazing. In addition, a livestock corral
was relocated away from the riparian zone and the
former site was revegetated. Irrigation pipeline proj-
ects eliminated ditch and canal erosion and reduced
seepage losses. More efficient sprinkler systems
further decreased erosion caused by irrigation return
flows. Lastly, an irrigation diversion was stabilized to
also reduce erosion.
LDCD continued monitoring water quality in NFCWC
until 1997. NFCWC data collected between 1991 and
1997 were summarized in a 2001 report in which
the data were deemed inconclusive due to several
factors, including climatic variability and an incom-
plete dataset. WDEQ completed additional BMP
effectiveness monitoring in 2003 and 2008 (Figure 2).
Results of the 2008 monitoring indicated that aquatic
life uses in NFCWC were no longer threatened by
habitat degradation (sediment) and nutrient enrich-
ment. Concentrations of total nitrogen, total phos-
phorus and chlorophyll a were low at sites within the
threatened segment, and no manifestation of excess
periphyton or aquatic macrophytes was observed at
any site. Stream banks, including those affected by
past incision, were moderately to highly stable and
covered with riparian vegetation. Temperature, dis-
solved oxygen, pH and chloride levels all met water
quality criteria. Macroinvertebrate samples at sites
within the threatened segment indicated that aquatic
life uses were fully supported. Based on the evidence
summarized above, WDEQ intends to remove this
threatened segment from the 2014 CWA section
303(d) list of impaired waters.
Partners and Funding
A total of $578,933 of CWA section 319 funds sup-
ported watershed restoration efforts. Nonfederal
matching funds totaling $1,867,344 were also
invested into watershed restoration, along with
approximately $220,000 of U.S. Department of
Agriculture Natural Resources Conservation Service
(NRCS) program funding. Numerous state and federal
resource management agencies supported the proj-
ect by providing guidance and technical assistance.
LDCD's major partners included numerous private
landowners, Crazy Woman Improvement District,
U.S. Forest Service, Bureau of Land Management,
NRCS, Wyoming State Forestry Division, Farm
Service Agency, University of Wyoming Cooperative
Extension Service, Wyoming Land Commission,
State Board of Water Control, WGFD, North Fork
Crazy Woman Irrigation District, Farm Loan Board,
Wyoming Water Development Commission and
county commissioners.
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-15-001PP
September 2015
For additional information contact:
Zach Byram
Lake DeSmet Conservation District
307-684-2526 • zach.byram@ldcd.org
Jennifer Zygmunt
WY Department of Environmental Quality
307-777-6080 • jennifer.zygmunt@wyo.gov
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