. Section 319
1 NONPOINT SOURCE PROGRAM SUCCESS STORY
Stakeholders Collaborated to Reduce Sediment in Creek x
Watprhndv ImnrnvpH Excessive sediment degraded habitat and threatened aquatic
" u" ' ' * • 'f ' * |jfe an(j coldwater fisheries uses in Sage Creek, prompting
the Wyoming Department of Environmental Quality (WDEQ) to add it to the state's 1996
Clean Water Act (CWA) section 303(d) list. A diverse stakeholder group led by the Saratoga-
Encampment-Rawlins Conservation District (SERCD) responded by implementing several
best management practices (BMPs) designed to reduce sediment carried in overland flow.
Sediment levels declined, and in 2008 WDEQ removed Sage Creek from the Wyoming
CWA section 303(d) list of impaired waters.
Problem
Sage Creek is in the North Platte River Basin of
southeastern Wyoming. The creek's headwaters are
along the continental divide in the northern foothills
of the Sierra Madre at an elevation of approximately
8,400 feet. The 263-square-mile Sage Creek water-
shed drains into the North Platte River near the
town of Saratoga (Figure 1). WDEQ classifies Sage
Creek as waterbody type 2AB; thus, it is protected
for the designated uses of drinking water, coldwater
game and nongame fisheries, fish consumption,
aquatic life, recreation, wildlife, industry, agricul-
ture and scenic value. The Sage Creek watershed
produces naturally high sediment loads because of
its highly erodible soils. Dam failures, road con-
struction and historic livestock grazing practices
have exacerbated the erosion, especially during
precipitation events and the spring snowmelt runoff
period (Figure 2).
SERCD collected data in 1996 indicating that exces-
sive sediment degraded habitat and threatened the
coldwater fishery and aquatic life designated uses
along a 14-mile section of lower Sage Creek. The
sediment traveled downstream, accumulating in
reservoirs and requiring increased processing time
and expense to municipal water treatment facilities.
WDEQ considered the sediment load to also be
a potential threat to the health of the North Platte
River's coldwater game fishery. Therefore, WDEQ
added Sage Creek to the state's 1996 CWA section
303(d) list for impairment to its coldwater fish and
aquatic life (other than fish) designated uses.
Figure 1. Photo of lower Sage Creek near
the confluence with the North Platte River.
Figure 2. Photo showing a high sediment
load in Sage Creek after a storm event.
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Project Highlights
In 1997 SERCD led a Sage Creek Watershed CWA
section 319 project that brought together local land-
owners, the U.S. Bureau of Land Management, the
U.S. Department of Agriculture's Natural Resources
Conservation Service and the Wyoming Game and
Fish Department. The partners implemented a
series of BMPs and monitored the effect of those
management changes by collecting sediment
and macroinvertebrate samples. BMPs, which
focused on restoring riparian habitat and reducing
sediment inputs to the stream carried by overland
flow, included using short-duration grazing, adding
riparian and drift fencing, developing off-channel
water sources, improving road management,
adding grade-control structures, and using water
diversions and vegetation as a sediment filters. The
partners anticipated that the project would improve
water quality in Sage Creek and reduce sediment
loading from the creek to the North Platte River.
Results
Data collected as part of the CWA section 319
project show that the BMPs effectively mitigated
the threats to the coldwater fishery and aquatic
life (other than fish) uses. Specifically, riparian
vegetation such as willows reestablished quickly,
stabilizing stream banks and converting the stream
channel from a wide and shallow configuration to
one that is narrower and deeper. Such in-stream
and riparian morphological changes translated into
cooler water temperatures and increased stream
power that better mobilizes fine sediment deposits
on the streambed.
Measurements of suspended sediment in Sage
Creek show a trend of decreasing concentration
after implementing BMPs. Mean total suspended
solids went from 529 milligrams per liter (mg/L) in
1998 to 80 mg/L in 2004. In addition, scientists col-
lected post-project macroinvertebrate samples on
the North Platte River above and below its conflu-
ence with Sage Creek using the Wyoming Stream
Integrity Index and River Invertebrate Prediction
and Classification System. Those data indicate that
both locations are fully supporting their aquatic
life (other than fish) designated use, and that the
sampling location below the confluence has a trend
of a slightly higher biological condition. That data
prompted WDEQ to remove Sage Creek from the
CWA section 303(d) list in 2008.
Partners and Funding
The project received a total of $126,149 through
CWA section 319 performance partnership grants
along with $88,148 of in-kind matching funds.
That funding supported implementing BMPs
and conducting effectiveness monitoring of the
management changes. SERCD led the Sage Creek
watershed CWA section 319 project, which was
a cooperative effort among local landowners, the
Bureau of Land Management, the Natural Resource
Conservation Service and the Wyoming Game and
Fish Department.
UJ
O
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-09-001QQ
December 2009
For additional information contact:
Richard Thorp, Wyoming Department of
Environmental Quality
307-777-3501 • rthorp@wyo.gov
Glen Leavengood, Saratoga-Encampment-Rawlins
Conservation District
307-326-8156 • Glen.leavengood@wy.nacdnet.net
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