Section 319
NONPOINT SOURCE PROGRAM SOGGESS STORY
Reducing Sediment from Logging Areas Improves the Swift Creek Watershed
Waterloo dies Improved
Erosion from logged areas and poorly maintained roads caused three
segments in the Swift Creek watershed (East Fork Swift Creek, West
Fork Swift Creek, and the Swift Creek main stem) to fail to support their aquatic life and cold water
fisheries designated uses. As a result, the Montana Department of Environmental Quality (MDEQ)
added the three segments to the state's Clean Water Act (CWA) section 303(d) list of impaired waters
in 1996. Implementing logging best management practices (BMPs) and improving roads have improved
water quality. Recent data show that Swift Creek fully meets its aquatic life and cold water fisheries
uses, prompting MDEQ to remove all three segments from the state's impaired waters list in 2012.
Problem
The Swift Creek watershed covers approximately
120 square miles in northwestern Montana. The
east and west forks of Swift Creek join to form the
Swift Creek main stem, which then flows in a south-
easterly direction before entering Whitefish Lake
near Whitefish, Montana (Figure 1). The Stillwater
State Forest manages 83 percent of the watershed;
most of the remaining 17 percent of land is man-
aged by the Flathead National Forest and private
timber companies. Swift Creek provides spawning
habitat for the bull trout, an endangered species.
Runoff from historically logged areas and poorly
maintained roads contributed excess pollutant
loads to the watershed's streams and rivers. The
soils in the vicinity of streams are composed of
reworked glacial sediments, generally unconsoli-
dated gravely loams and gravely silt loams, and they
are easily eroded under both natural and altered
landscape conditions.
Data collected after 1976 showed that total phos-
phorus (TP) levels had exceeded 50 micrograms per
liter (jUg/L) numerous times. These data, along with
observed high rates of erosion, prompted MDEQ
to identify all three segments of Swift Creek (Swift
Creek main stem, East Fork Swift Creek, and West
Fork Swift Creek) in 1989 as impaired for not fully
supporting the aquatic life and cold water fisher-
ies designated uses due to high levels of nutrients
(East Fork and main stem Swift Creek only) and
sediment. As a result, MDEQ added the three seg-
ments to Montana's 1996 CWA section 303(d) list of
impaired waters. The probable impairment sources
included silviculture and roads.
Swift Creek Watershed
Figure 1. Swift Creek is in northwestern Montana.
Project Highlights
In the early 1990s the Montana legislature passed
two state regulatory authorities that helped to
reduce the water quality impacts from timber
harvesting and forestry operations. The Forestry
Best Management Practices (BMP) Notification Law
(1989) requires landowners and operators to notify
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Results
Figure 2. Projects partners installed bridges over
Swift Creek to reduce sediment.
the state before conducting forest practices on
private lands to ensure that BMPs are adopted to
minimize nonpoint source pollution. The Streamside
Management Zone (SMZ) Law (1991) regulates for-
est practices along streams to protect and maintain
the SMZ (i.e., the riparian area), which serves as a
natural filter of vegetation.
Logging still occurs in the watershed, but the
Stillwater State Forest, Flathead National Forest,
and Plum Creek Timber Company have native fish
habitat conservation plans in place to help them
protect the more sensitive riparian areas and evalu-
ate environmental impacts before logging. The
forest landowners have continued to improve road
infrastructure since the early 1990s.
Since 2003 MDEQ has cooperated with the Swift
Creek Coalition and the Whitefish County Water
and Sewer District on a phased approach to total
maximum daily load (TMDL) development and
watershed restoration for the Flathead Stillwater
watershed, which includes Swift Creek. The
Whitefish County Water and Sewer District secured
three CWA section 319 grants (in 2002, 2003, and
2005) that supported monitoring water quality,
reviewing existing data, and developing and imple-
menting restoration activities. The restoration activi-
ties included replacing approximately 15 culverts
and three bridges designed to reduce sediment
from target areas in the Swift Creek watershed
(Figure 2). In addition, two pollutant-source studies
conducted on behalf of the Swift Creek Coalition
helped to identify and quantify pollutants from
natural sources and human-caused activities.
Montana's nutrient criteria for the Northern Rockies
Ecoregion are 30/jg/L for TP and 300/jg/L for total
nitrogen (TN) for the July 1-September 30 grow-
ing season. In 2008 MDEQ reviewed existing data
from all monitoring stations (one on each segment,
one at the downstream end of Swift Creek, and
one on a tributary) and found thatTP levels were
consistently below 30/jg/L at all the sites. The
same report also found TN values were well below
300/jg/L and generally below 100/jg/L. The review
showed that chlorophyll a data collected in 2003 on
all segments ranged from 14.1 to 71 milligrams per
square meter (mg/m2), well below the criterion of
125 mg/m2 established for the ecoregion.
In addition, a review of sediment data from 1997
(after forestry-related laws were enacted) through
2007 showed thatfine sediment (less than 6.35 mil-
limeters in diameter) on the stream bottom ranged
from 30.3 to 33.7 percent. These values are below
the 35 percent threshold value at which Montana
Fish, Wildlife, and Parks and the U.S. Forest Service
consider bull trout spawning to be threatened.
Additionally, pool frequency (eight to 15 pools per
1,000 feet), large woody debris (19-213 instances
per 1,000 feet), and stream width-to-depth ratios
(measured ranging from 12.7 to 22.1) fell within the
range of expected conditions for streams fully sup-
porting the aquatic life use.
MDEQ performed a water quality reassessment
using all existing data in 2009-2011 and deter-
mined that the three segments fully support their
aquatic life and cold water fisheries designated
uses. As a result, MDEQ removed all three—East
Fork Swift Creek (MT76P003_030, 9.18 miles),
West Fork Swift Creek (MT76P003_040, 9.53
miles), and Swift Creek (headwaters to mouth;
MT76P003_020, 17.28 miles)—from the state's
list of impaired waters in 2012.
Partners and Funding
The major partners included MDEQ, the Montana
Department of Natural Resources and Conservation
(DNRC), the Plum Creek Timber Company, the Swift
Creek Coalition, and the Whitefish County Water and
Sewer District. MDEQ provided a total of $130,000
of CWA section 319 funds, much of which supported
watershed assessment work and water quality res-
toration plan development. The Plum CreekTimber
Company, the U.S. Forest Service, and DNRC used
their own funding to implement road and logging
restoration and forestry management activities.
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U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-14-001FF
May 2014
For additional information contact:
Robert Ray
Montana Department of Environmental Quality
Clean Water Act Section 319 Program Manager
406-444-5319 • rray@mt.gov
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