BASIN
 
The COTC is located in northwest Montana and
extends in to the southeast corner of British Columbia. The
basin covers an area of roughly 30,786 Km². The Canadian
portion of the basin covers an area of 1,560 Km².
Topographically, the basin extends from a
maximum 3,092 m (Mt Stimson) to a low of 753 m near Perma,
Montana. Within the 30,786 km² basin over 80% of the basin
is forested-alpine areas, 8% rangeland, 7% cropland and 1%
urban. 4% of the basin is covered by water.
About 1,560 km² of the North Fork of the
Flathead River watershed lies in British Columbia, Canada.
This portion of the watershed is managed by the BC Ministry
of Environment, Lands and Parks and contains only a small
amount of private holdings. Land management in the larger
U.S. part of the Flathead basin involves the U.S. Forest Service,
National Park Service, State of Montana, Flathead and Lake
Counties, the Confederated Salish and Kootenai Tribes, private
industrial and private non- industrial land owners.
Intensive Study Area(ISA)
 Within
the greater COTC we propose a more intensive study corridor
called The Crown Cross-shed. This study zone
forms an "X" like configuration across the COTC.
The corridor consists of areas that are highly suited for
intensive field research and instrumentation localities. These
specific localities are refered to as Intensive Study Areas
(ISA).
ISA Examples:
The Gibson reservoir area is located in the
south-east portion of the COTC. This area drains the heart
of the Bob Marshal Wilderness. Serving as a major water source
for agriculture, ground water recharge, and recreation this
headwater of the Sun River is a strong canidate for an ISA.
Wildhorse Island is the largest fresh water
island west of the Mississippi. It is located in the center
of Flathead Lake. The Island is perfectly suited for monitoring
many important hydrologic and climatological processes.
Basin Characteristics
The annual discharge of the Flathead River
system is 10.6 billion cubic meters. The North Fork, Middle
Fork and South Fork of the Flathead river generate 80% of
the annual stream discharge at the river mouth. The Swan River
basin provides 9% of the annual discharge, and the Whitefish
and Stillwater rivers, draining the northwestern portion of
the basin, generate 5% of the annual flow. Portions of the
watershed regulated by dams include the South Fork of the
Flathead River that contains the 95 km² Hungry Horse Reservoir,
the outlet of Flathead lake regulated by Kerr dam and a small
dam on the Swan River near Big Fork, MT.
.
The climate is dominated by the Pacific coastal
systems in the winter that are occasionally overridden by
the continental air masses originating north and east of the
area. The average winter temperature in Kalispell is 7C and
summer temperatures typically range from 20C to 27C. The large
variation in topography results in high mountain areas receiving
200 to 300 cm/y of precipitation with snow packs reaching
6 m. In contrast the valleys receive 39 to 50 cm/y (FHEIS,
1983). The growing season is estimated at 120 to 130 days
in the main Flathead Valley with an extended growing season
of 140 days along the east shore of Flathead Lake.
Studies of glaciers in the Glacier National
Park region recorded 150 glaciers in 1850 and 37 in 2004.
Forecasts suggest all glaciers will be gone within 40 years.
These studies are associated with sets of long term climatic
records collected by the park and USGS researchers.
Mountain vegetation below the 2,450 m tree
line is dominated by Englemann spruce, Whitebark pine and
subalpine fir. At lower elevations Douglas- fir and zones
of ponderosa pine are present. In some wet areas red cedar
and western hemlock are observed. Wildfires allow lodge pole
pine and western larch to dominate burned areas. Grasses such
as rough fescue, Idaho fescue and bluebunch wheat grass dominate
the dry valley floors and hills in the southern portion of
the basin. Riparian zones are dominated by black cotton wood,
some paper birch and shrubs (FHEIS, 1983).
The basin contains 12 hydrologic landscape
regions (USGS). It is dominated by semi arid mountains with
impermeable bedrock. Other major landscapes include sub-humid
plans with impermeable soils and permeable bedrock, humid
plains with permeable soils and impermeable bedrock, and semiarid
plains with impermeable soils and bedrock. Valley floors are
classified as arid to semiarid plans and plateaus with permeable
soils and bedrock. A portion of the mountain region is classified
as humid mountains with permeable soils and impermeable bedrock.
The basin contains over 500 lakes ranging
from glacial tarns to the 510 km² oligotrophic Flathead
Lake, the largest naturally occurring freshwater lake west
of the Mississippi River. It occupies an extensional half-graben
that is bounded on the east by the seismically-active Mission
Mountain normal fault. Flathead Lake is locate at the former
ice margin of the Cordilleran Ice Sheet during the most recent
(Pinedale) glaciation. Sediments within the lake contain a
very well preserved record of deglaciation associated with
retreat of the Cordilleran Ice Sheet.
Water management practices include water diversions
for irrigation, power generation, flood control, flows for
endangered, threatened and listed species, and recreation.
Federal, state, tribal and local units are involved in water
management. Management actions include local needs and national
mandates.
 Stream
flows are snow-melt dominated and underpinned by groundwater
baseflow. The site headwaters contain 37 glaciers and thousands
of square kilometers of watersheds in which fire and disease
are the only disturbances. In contrast, the COTC also contains
watersheds at multiple scales that were dominated by glaciers
within the last 100 years but are now glacier free, impacted
by timber harvests and fires of varying ages to varying degrees,
modified by water management practices including irrigation
diversion and dams, and altered by development for homes,
cities and agriculture.
For several thousand years this system has
been dominated by snow-melt runoff and moderated by large
quantities of water stored in Glacial ice. However, the timing
and magnitude of droughts and summer flows have changed dramatically.
With the information that can be gleaned from sediment cores
and landscape records at different scales, this COTC will
provide scientists with opportunities to establish baseline
watershed conditions and data on natural hydrologic variability.
Such a context frames the current and further observations
and assists with translating measured changes into links with
the varied COTC ecosystems.
The COTC watersheds are some of the only pristine
watersheds left in the contiguous U.S.. They provide critical
habitat for key species including the native threaten bull
trout and lynx, and the listed westslope cutthroat trout,
bald eagle, gray wolf and the grizzly bear.
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