Section 319
               NONPOINT SOURCE PROGRAM SUCCESS STURY
 Implementing Grazing Best Management Practices Improves Shoshone Creek
Waterbody  Improved
                                Recreation, livestock grazing and other activities on public and
                                private lands along southern Idaho's Shoshone Creek led to erosion
and the loss of riparian cover. Data indicated that the creek failed to meet its beneficial uses for cold
water aquatic life and salmonid spawning because of sediment and temperature impairments. As a
result, numerous portions of Shoshone Creek were included on the Clean Water Act (CWA) section
303(d) list between 1994 and 2008. Public and private partners have implemented best management
practices (BMPs) to reduce erosion and improve riparian conditions. Recent bioassessment data
collected along South Fork Shoshone Creek indicate that water quality conditions are improving as a
result of restoration efforts.
 Problem
 The 218,600-acre Shoshone Creek watershed is
 west of Idaho's Cassia Mountains in Twin Falls
 County and drains into Salmon Falls Creek in Elko
 County, Nevada (Figure 1). Landowners include
 the U.S. Department of Interior's Bureau of Land
 Management (BLM) (44.7 percent), the U.S. Forest
 Service (USFS) (20.3 percent), the Idaho state gov-
 ernment (2 percent) and private entities (33 percent).

 Rangelands encompass approximately 58 percent
 of the Shoshone Creek watershed. Historical grazing
 systems allowed cattle to heavily graze meadows
 and riparian habitats, causing decreased stream-
 bank stability and damaging native vegetation. This,
 in turn, allowed for the invasion of noxious weeds,
 a loss of beneficial riparian vegetation and the ero-
 sion of soil. Data collected in the 1990s and 2000s
 indicated that Shoshone Creek failed to support its
 beneficial uses (cold water aquatic life and salmonid
 spawning) because of  elevated temperatures and
 excess sediment. As a result, numerous assessment
 units (AUs) within the Shoshone Creek watershed
 were added to the CWA section 303(d)list — two by
 the U.S. Environmental Protection Agency in  1994
 and two by the Idaho Department of Environmental
 Quality (DEQ) in 2008.

 In 2007 DEQ completed a subbasin assessment and
 total maximum daily load (TMDL) for the listed AUs
 within the Salmon Falls Creek subbasin, including
 those in the Shoshone Creek watershed. To allow
 Shoshone Creek to meet water quality standards and
 support its beneficial uses, the TMDL established
 reduction goals for both temperature (a 40 percent
 reduction) and sediment (a 65 percent reduction).
                                            Figure 1. Shoshone Creek is in
                                            southern Idaho. Yellow dots represent
                                            monitoring locations in the upper
                                            portion of Shoshone Creek AU
                                            ID17040213SK016 _ 03 (main stem).


                                            Project Highlights
                                            Partners have worked to improve Shoshone Creek
                                            since the early 1980s. For example, in the Magic
                                            Common Grazing Allotment, BLM excluded live-
                                            stock from the stream (0.15 mile and 0.25 mile in
                                            1982 and 1987,  respectively), instituted prescribed
                                            grazing in 2000 and installed fencing to protect a
                                            sensitive spring in 2003. In the Kerr-Lost Allotment,
                                            BLM excluded livestock from 0.25 mile of Shoshone
                                            Creek in 1982 and instituted prescribed grazing
                                            in 1987. In 2000 BLM adopted prescribed grazing
                                            in the Horse Creek Allotment. As of 2014, all of

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Shoshone Creek under BLM administration is either
excluded from livestock grazing or is managed as
riparian pasture (i.e., allows for prescribed grazing).

In July 2013, staff from the USFS' Sawtooth
National Forest developed a land and resources
management plan that describes the agency's
water management goals. Even before developing
this plan, the USFS was implementing projects to
protect soil, water, riparian and aquatic resources.
In 2004 the USFS built fences on the Rock Creek
C&H Allotment to restrict grazing along the creek. In
addition, the USFS placed boulders along the main
road to prevent motor vehicle access to the creek.
                                                                 Table 1. South Fork Shoshone Creek Beneficial Use
                                                                 Reconnaissance Program Wadeable Streams Rapid
                                                                 Bioassessment Data
                          In 2007 the USFS part-
                          nered with the Twin
                          Falls Soil and Water
                          Conservation  District
                          (SWCD)and the
                          Western Stockgrowers
                          Grazing Association
                          (WSGA)to install pip-
                          ing from a spring to a
                          10,000-gallon holding
                          tank. The water is then
                          gravity-fed to  19 live-
                          stock watering troughs
                          (Figure 2). These
                          troughs serve three
different grazing pastures as part of a rotational
grazing system on 2,354 acres and help to  protect
approximately 4 miles of Shoshone Creek riparian
area. The WSGA and USFS developed  and imple-
mented a grazing management plan for the area in
2008. To supplement water supplies during drought
periods, they installed a second,  6,000-gallon stor-
age tank, in June 2014. The WSGA also purchased
two mobile pumps powered by solar panels to
provide additional alternative water sources.
Figure 2. Project partners installed
alternate water sources to keep
livestock away from Shoshone Creek.
Results
DEQ collected Beneficial Use Reconnaissance
Program wadeable streams rapid bioas-
sessment data in the upper portion of AU
ID17040213SK016 _  03 in 1997, 2005 and 2011.
These limited data, which capture and assess only
the uppermost few miles of an 11.3-mile-long AU,
show that the macroinvertebrates scores have
improved from a condition  rating of 2 to 3 (Table 1).
The habitat is also responding favorably, but at a
slower pace. The SFI (stream fish index) score did


Date
1997
2005
2011
Stream
Macroinvertebrate
Index (SMI) Score
44.9
58.5
72.4
SMI
Condition
Rating1
2
3
3
Stream Habitat
Index (SHI)
Score
46
43
53
SHI
Condition
Rating1
1
1
2
                                                  1  The SMI, SFI and SHI results are used to evaluate support of cold water aquatic
                                                    life. The scoring criteria are derived from percentile categories of the reference
                                                    condition in different bioregions (i.e., a "condition rating"). Condition ratings
                                                    include 0 (below minimum of reference condition), 1 (less than 10th percentile
                                                    of reference condition), 2 (between 10th and 25th percentile of reference condi-
                                                    tion), or 3 (more than 25th percentile of reference condition). For more informa-
                                                    tion, see section 6 of Idaho's Water Body Assessment Guidance (January 2002).

                                                  not improve over the sampling period; however,
                                                  numerous native fish species have been present
                                                  during all sampling events. Juvenile salmonid spe-
                                                  cies were present in both 1997 and 2011, indicating
                                                  good quality water. DEQ believes that the  low SFI
                                                  score might not reflect conditions on-the-ground;
                                                  therefore, additional fish surveys are warranted.

                                                  These  data indicate that restoration efforts are
                                                  helping to improve water quality in the upper por-
                                                  tion of Shoshone  Creek AU ID17040213SK016_03.
                                                  Additional data will need to be collected to assess
                                                  water quality conditions elsewhere within  this and
                                                  other Shoshone Creek AUs.
                                                                 Partners and Funding
                                                                 Numerous partners have provided technical
                                                                 or financial assistance to help landowners and
                                                                 producers implement BMPs in the Shoshone Creek
                                                                 watershed. Partners include the Twin Falls SWCD,
                                                                 USFS, BLM, the WSGA, the U.S. Department of
                                                                 Agriculture's Natural Resources Conservation
                                                                 Service, and the Idaho Soil and Water Conservation
                                                                 Commission.

                                                                 The Twin Falls SWCD received $96,160 ($85,700
                                                                 in 2007 and $10,460 in  2014) in U.S. Environmental
                                                                 Protection Agency CWA section 319 funding
                                                                 from DEQ to  install storage tanks, piping and
                                                                 water troughs to support rotational grazing. The
                                                                 WSGA provided significant matching funds for
                                                                 the CWA section 319 projects. DEQ and the Idaho
                                                                 Association of Soil Conservation Districts have col-
                                                                 lected monitoring data  and have provided support
                                                                 for assessment and planning efforts.
UJ
O
     U.S. Environmental Protection Agency
     Office of Water
     Washington, DC

     EPA841-F-14-001GGG
     September 2014
                                                                 For additional information contact:
                                                                 Katie Shewmaker
                                                                 TMDL Implementation Coordinator
                                                                 Idaho Department of Environmental Quality
                                                                 208-736-2190 • Katie.Shewmaker@deq.idaho.gov

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