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Gales Creek Large Woody Debris Inventory Report
Submitted to Tualatin River Watershed
Council
By Michele Koehler, M.S. and Nick Haxton,
M.S. ABR, Inc.
Environmental Research and Services
February 27, 2006
PDF
File (Downloadable file, 8.3 MB)
Website Table of Contents
Introduction
In 1998, the Tualatin River Watershed
Council (TRWC) produced a Watershed Assessment
for Gales Creek (Breuner 1998) that provided
detailed information on the past and present
condition of the watershed and pointed the
TRWC in the direction of sustainable watershed
management. This document cited several
fisheries-related concerns, including fish
habitat, fish migration barriers, riparian
condition, channel modifications, water
quality and water use issues and sedimentation
(Breuner 1998). More specifically, the document
identified needs for salmonid spawning,
rearing and overwintering habitat, and a
general call for increasing habitat diversity
within the creek. The document cited the
need for an assessment of existing large
woody debris (LWD) to better understand
current patterns in stream structure and
habitat complexity within the Gales Creek
watershed.
Towards these ends, in 2003, the TRWC
completed the Lower Gales Creek Habitat
Enhancement Plan with the purpose of identifying
priority areas and sites for improving anadromous
fish habitat over a five-year period. Through
a review of the physical, biological and
land use characteristics of Gales Creek,
a four-mile stretch from Prickett Creek
to Clear Creek was identified as a priority
area for enhancement (TRWC 2003). The Enhancement
Plan was developed for this area of Gales
Creek in response to a U.S. Bureau of Reclamation
(BOR) request to identify factors limiting
winter steelhead (Oncorhynchus mykiss)
and other salmonid production and to plan
habitat enhancement activities with these
species in mind and in response to the fisheries
needs identified in the 1998 Gales Creek
Watershed Assessment.
Nine habitat enhancement projects identified
in the Enhancement Plan require further
information in order to proceed with design,
permitting and project implementation steps.
Five of these projects require information
on existing numbers of LWD for project planning.
ABR, Inc. conducted LWD inventories in Gales
Creek on September 28 and October 4, 2005.
The objective of the inventories was to
evaluate the current levels of large wood
in Lower Gales Creek. Surveys identified
existing LWD, log jams and areas prone to
recruitment of LWD from the riparian zone.
This report documents the results of the
LWD surveys on Gales Creek.
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