Section 319
NONPOINT SOURCE PROGRAM SOGGESS STORY
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Forestry Best Management Practices Improve Water Quality
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Historic forestry activities impaired Lower Piper Creek and Upper and
Lower Goat Creek, prompting Montana to add these three segments
to its 1996 Clean Water Act section 303(d) list of impaired waters. Landowners collaborated with
federal and state agencies to implement forestry best management practices (BMPs) in Goat and Piper
creeks. Water quality improved, and in 2006 Montana removed Upper Goat Creek from the 303(d) list
for nutrients and Lower Piper Creek and Lower Goat Creek for siltation.
Problem
Piper and Goat creeks empty into
Swan River in northwestern Montana
(Figure 1). Timber production is an
important economic resource and a
key source of sediment pollution in the
Swan River watershed. Most of the
land is owned and managed by the U.S.
Forest Service, the Swan River State
Forest and Plum Creek Timber Company
(PCTC). Timber activities that generated
sediment and nutrient pollution included
building forest roads, harvesting timber
from riparian areas, disturbing forest
ground, and removing trees and canopy
cover. Private developers contributed
additional pollution by disturbing ripar-
ian areas, encroaching on streams,
building septic systems and not ade-
quately maintaining private roads.
Montana Department of Environmental
Quality (MDEQ) added Piper Creek and
the entire length of Goat Creek to its
1996 303(d) list for partial support of aquatic
life and cold-water fish. During 2002 revisions
to the 303(d) list, MDEQ refined the causes
of impairment to specify that nutrients and
suspended solids impaired a 9-mile segment
of Upper Goat Creek and that siltation impaired
both a 1-mile segment of Lower Goat Creek and
a 4-mile segment of Piper Creek.
In Upper Goat Creek, MDEQ indicated that total
suspended sediment and nutrient concentra-
tions exceeded the state standard, which
requires "no increases in these pollutants are
allowed above naturally occurring concentra-
tions that will render the waters harmful or
create a nuisance for its classified uses." The
Goat Creek TMDL established a total sus-
pended solids (TSS) target of 30 milligrams per
liter (mg/L). This target was based on reference
Legend
Flathead Indian Reservation
Mission Mountains Wilderness
Swan River State Forest
Flathead National Forest
Plum Creek Timber Company Land
Other Private Land
Figure 1. Map of the Swan River watershed.
streams in the Swan Lake drainage area, which
have peakflow TSS values in the 15 to 20 mg/L
range, indicating a range of naturally occurring
conditions.
Increased erosion caused nutrient concentra-
tions to rise as well. MDEQ analyzed nutrient
data from various sources, which indicated that
Upper Goat Creek nitrate levels ranged from
0.06 to 0.10 mg/L, and that nitrite + nitrate
levels were around 0.07 mg/L. Both estimates
exceeded background levels.
In 1989 MDEQ assessed Lower Goat Creek and
found elevated levels of sediment deposition
that contributed to an embedded substrate
and braiding of the stream channel. This seg-
ment of Goat Creek was impaired by excess
siltation, particularly near the mouth, because
of logging road runoff that caused banks to
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rapidly erode. In Piper Creek, the MDEQ stream
reach assessment showed that fine sediment
in the channel—mainly from timber harvest and
roads—moderately impaired the creek. MDEQ
found that 53 percent of the stream reach had
a less-than-healthy riparian plant community
because of timber harvest.
Project Highlights
Water quality improvement efforts have
been underway for the past 20 years. In 1989
Montana adopted forestry BMPs. In 1991 the
state enacted a Streamside Management Zone
law, which limits the removal of riparian vegeta-
tion for commercial timber harvest and the use
of potentially harmful timber harvest practices
near waterbodies.
Swan River and several of its tributaries provide
significant habitat for bull trout, a federally listed
threatened species. In 1997 PCTC met with the
U.S. Fish and Wildlife Service to begin develop-
ing the Native Fish Habitat Conservation Plan.
Under this plan, PCTC agreed to upgrade old
roads for which it has direct or shared respon-
sibility to an improved erosion control standard
by the end of 2015.
In 2004 MDEQ completed a Water Quality Plan
and Total Maximum Daily Loads (TMDLs) for
the Swan Lake Watershed. A key element of the
plan is to reduce excess sediment delivery to
streams from roads throughout the Swan Lake
Watershed. PCTC installed BMPs on existing
roads in the Goat and Piper Creek watersheds,
including relief culverts and drivable drain dips
that redirect sediment carried in snowmelt
or runoff from the road
to infiltration areas on
adjacent slopes. In addi-
tion, PCTC designed and
constructed new roads
with enhanced BMPs
that exceed existing state
rules and current BMP
standards.
Figure 2. Roadside catchments
capture sediment from runoff
and allow water to infiltrate and
sediment to settle out.
The U.S. Forest Service
added roadside drainage
catchments that accumu-
late runoff and sediment
on public lands (Figure 2).
The Montana Department
of Natural Resources and Conservation
(MDNRC) constructed road BMPs and imple-
mented a no-harvest buffer zone along a por-
tion of Goat Creek on Swan Lake State Forest
lands. MDNRC also completed other drainage
work in a major tributary to Goat Creek.
Results
This multifaceted approach has successfully
decreased concentrations of suspended solids
and nutrients in Goat and Piper creeks over time.
In fact, when MDEQ assessed water quality
as part of the 2004 TMDL, the data indicated
that Goat and Piper creeks met water quality
standards for TSS and nutrients. The impair-
ment indicators seen in earlier MDEQ stream
assessment were no longer obvious. Therefore,
although sediment and stream channel condi-
tions might not be pristine, MDEQ believes that
they are within the range of naturally occurring
and should no longer be considered impaired.
Moreover, the periphyton results do not raise
sediment or habitat concerns.
PCTC performed additional water quality
assessments and estimated that road improve-
ment efforts have led to a 29 percent and 71
percent decrease in sediment delivered to Goat
and Piper creeks, respectively, helping the
streams meet the TMDL TSS target of 30 mg/L.
As a result, in 2006 MDEQ removed Lower
Piper and Lower Goat Creeks from the state's
303(d) list for siltation and Upper Goat Creek for
nutrients.
Partners and Funding
Approximately $409,000 in EPA section 319
grants supported the Swan Ecosystem Center.
The center coordinated the Swan Watershed
Group and Technical Advisory Group, which
helped to develop the Swan Lake Watershed
TMDL. Organizations that helped to restore and
monitor water quality include MDEQ, MDNRC;
Flathead Basin Commission; Flathead Biological
Station, University of Montana; Flathead
National Forest; Friends of the Wild Swan;
Lake County; Missoula County; Montana Fish,
Wildlife and Parks; PCTC; Swan Ecosystem
Center; The Trust for Public Land and others.
The U.S. Forest Service, MDNRC, and PCTC
have funded their own restoration projects in
Goat and Piper creeks.
I
U.S. Environmental Protection Agency
Off ice of Water
Washington, DC
EPA841-F-08-001JJ
February 2009
For additional information contact:
Robert Ray
Montana Department of Environmental Quality
Phone: 406-444-5319
Ann Dahl
Swan Ecosystem Center
Phone: 406-754-3137
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