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When one thinks of the Pacific
Northwest, most picture deep dark forests
with rain-swollen rivers hiding salmon and steelhead
fresh from the ocean. Although this picture does
mirror many river systems in the Northwest, it
really portrays only the western one-third of the
States of Washington and Oregon. The diversity
of stream types in the Northwest is truly amazing-
from desert washes to alpine brooks, to spring-fed
meadow creeks, boulder-strewn cascades, and the
butte-rimmed rapids of large rivers like the Upper
Columbia and Snake Rivers. Over 20,000 miles of
these streams in the Region support a wide range
of aquatic organisms, including native cold-water
and warm-water fish, as well as a number of fish
species introduced to provide increased fishing
opportunities.
The Forest Service manages stream habitats to support
healthy populations of these fish stocks, protect
water quality, and to provide opportunities for human
uses such as hiking, fishing, educational programs
and fish viewing. Management is based on sound scientific
information (see Inventory and Monitoring sections)
and comprehensive, integrated watershed analyses.
Protection is assured through a system of aquatic
refugia and riparian reserves. Where watershed analysis
highlights impacted areas, restoration programs are
developed (at watershed scale) to help recover natural
functions and processes. This management applies
to all streams regardless of size- in fact, restoration
activities tend to focus on small streams (including
intermittent tributaries) and headwater areas because
of their importance in supplying high quality water
and their function as seasonal refuges for aquatic
organsims.
"Restoration emphasizes
identification and recovery of critical watershed
processes and function. Rock Creek, in a burned,
logged and grazed area on Mt. Hood National Forest,
shows stream and riparian recovery following fencing,
planting and in-channel treatments from 1984-1999" (Photos
above: 1984 Pre-project, 1986 Post-project and Recovery
by 1999).
The emphasis for restoration is to identify and
fix causes of problems and not symptoms. Therefore,
stream restoration typically starts outside the stream
channel, from the ridge-tops working downhill, correcting
any erosion/slope stability and road related problems
(including fish passage and drainage). Riparian and
floodplains are usually next, replacing structure/roughness,
planting, and/or recovering wetland/off-channel features.
Once all these factors have been addressed, restoration
of channel features, such as channel form (cross-section
profile, length/meander pattern, amount and types
of pools) and/or structural attributes (logs or boulders)
are considered. An excellent example of channel restoration
is Enchanted Valley,
where a reconstructed meandering channel has replaced
an eroding ditch in a coastal wetland area.
Refer to the regional Forest
Specific page for additional examples of stream
habitat restoration, and Monitoring for
examples of evaluations of stream protection and
restoration practices. |