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  Assessment of Factors Limiting Salmon Production in Devil’s Hole Creek PDF Format - [4.05MB]
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Introduction
The Washington Department of Fish and Wildlife Wild Salmon Production Unit was contracted
by the Navy in 1998 through 2000 (Navy contract #’s N6871198LT80043, and
N6871199LT90019) to provide a species and habitat assessment and corrective design project for
the Devil’s Hole watershed on the Naval Submarine Base, Bangor, Washington. The purpose of
this project was to identify species use and determine factors negatively affecting salmon
production in the Devil’s Hole watershed and to recommend corrective measures for these
factors.
This is the final report for the project. It describes the methods and results of the species and
habitat assessment work conducted during the spring through summer periods of 1999 and 2000.
Elements evaluated included current fish use of the watershed, summer stream temperatures,
spawning habitat quality, macroinvertebrate indicators, bank and riparian conditions, channel
morphology, stream habitat condition, fish passage conditions, and the location/impact of point
source discharges for all of the stream network accessible to anadromous salmonids as well as
most of that used by resident salmonids. The report also describes factors we believe are most
limiting to anadromous salmonids and provides recommendations for corrective measures to
improve utilization and survival of salmonids in the Devil’s Hole watershed.
Site Description
The Bangor Naval Submarine Base is located adjacent to Hood Canal on the northern Kitsap
Peninsula (Figure 1). The facility is 6,692-acres in size. The site was first purchased by the
Navy in 1942. After serving as a U.S. Ammunition Depot for a number of years, the site was
established as a submarine base in 1977. The base has grown substantially during the 1990's as a
result of Base Closure and Realignment actions in 1991 and 1993.
The entire Devil’s Hole Creek watershed is within the Bangor Submarine Base complex (Figure
1). The mainstem Devil’s Hole Creek travels in a northerly direction before entering Hood Canal
approximately 1/4-mile southwest of the Delta Pier. The watershed is located in township T26N,
range R1E, sections 18, 19, 20, and 30; and township T26N, range R1W, sections 24 and 25.
Total area of the watershed is 2.61 mi2 (United States Geological Survey data).
A reservoir was created near the mouth of the stream in the 1940's when Sea Lion Road was
constructed (Tom James pers. comm.). The reservoir, Bangor Lake or Devil’s Hole Lake, has a
surface area of about 2.6-hectares (Wolcott 1961). A fishway was constructed at the lake outlet in
1979 to provide access to the watershed for anadromous salmonids (Tom James pers. comm.).
Potentially fish-bearing stream channels in the watershed include the mainstem Devil’s Hole
Creek and five un-named tributaries (Figure 2). Four of the tributaries are right-bank tributaries
(i.e., enter Devil’s Hole Creek from the right-side of the stream when looking downstream) and
one is a left-bank tributary. These have been arbitrarily named for identification purposes as
RB1-4 and LB1. RB1 enters Bangor Lake, while the other tributaries enter Devil’s Hole Creek
upstream of the reservoir.
The climate in the region has a strong maritime influence characterized by cool, dry summers and
mild, wet winters. Precipitation averages 50 to 65-inches per year with over 98% falling in the
form of rain (WDNR 1995). Only 5 to 10% of the annual precipitation occurs between July and
September.
The watershed has been highly influenced by the advance and retreat of continental glaciers over
the last two million years. Surficial sediments have been primarily influenced by the most-recent
Fraser Glacier, which occurred from 15,000 to 13,500 years ago. Sedimentary deposits left by
the glacier include unconsolidated outwash (comprised of sands and gravel), till, and lacustrine
deposits (primarily comprised of silt and clay) (WDNR 1995). Of these, outwash deposits with a
high composition of sand are particularly common in the Devil’s Hole watershed and have a
substantial effect on channel morphology and fish habitat.
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