EPA's Vessel General Permit and Small Vessel General

quality and quantity, natural cover, forage, adequate passage conditions, and floodplain
connectivity. Of 52 subbasins reviewed in NMFS' assessment of critical habitat for the Lower
Columbia River Chinook salmon ESU, 13 subbasins were rated as having a medium
conservation value, four were rated as low, and the remaining subbasins (35), were rated as
having a high conservation value to Lower Columbia River Chinook salmon. Factors
contributing to the downward trends in this ESU are hydromorphological changes resulting from
hydropower development, loss of tidal marsh and swamp habitat, and degraded freshwater and
marine habitat from industrial harbor and port development, and urban development. Limiting
factors identified for this species include reduced access to spawning/rearing habitat in
tributaries, hatchery impacts, loss of habitat diversity and channel stability in tributaries,
excessive fine sediment in spawning gravels, elevated water temperature in tributaries, and
harvest impacts.
Final Protective Regulations
On June 28, 2005, as part of the final listing determinations for 16 ESUs of West Coast salmon,
NMFS amended and streamlined the 4(d) protective regulations for threatened salmon and
steelhead (70 FR 37160) as described in the Protective Regulations for Threatened Salmonid
Species section of this document. Under this change, the section 4(d) protections apply to
natural and hatchery fish with an intact adipose fin, but not to listed hatchery fish that have had
their adipose fin removed prior to release into the wild. The amended June 2005 4(d) rule
applies to the Lower Columbia River Chinook salmon ESU.
Upper Columbia River Spring-run Chinook Salmon
Distribution and Description of the Listed Species
The Upper Columbia River spring-run Chinook salmon ESU includes all naturally spawned
populations of Chinook salmon in all river reaches accessible to Chinook salmon in Columbia
River tributaries upstream of Rock Island Dam and downstream of Chief Joseph Dam in
Washington, excluding the Okanogan River. Six artificial propagation programs are part of this
ESU. Spring-run Chinook salmon currently spawn in only three river basins above Rock Island
Dam: the Wenatchee, Entiat, and Methow Rivers (Good et al. 2005).
Status and Trends
NMFS listed Upper Columbia River spring-run Chinook salmon as endangered on March 24,
1999 (64 FR 14308), and reaffirmed their status as endangered on June 28, 2005 (70 FR 37160),
because they had been reduced to small populations in three watersheds. Based on redd count
data series, spawning escapements for the Wenatchee, Entiat, and Methow rivers have declined
an average of 5.6%, 4.8%, and 6.3% per year, respectively, since 1958. In the most recent 5-year
geometric mean (1997 to 2001), spawning escapement for naturally produced fish was 273 for
the Wenatchee population, 65 for the Entiat population, and 282 for the Methow population, only
8% to 15% of the minimum abundance thresholds, although escapement increased substantially
in 2000 and 2001 in all three river systems. Based on 1980-2004 returns, the average annual
growth rate for this ESU is estimated at 0.93 (meaning the population is not replacing itself;
Fisher and Hinrichsen 2006). Assuming that population growth rates were to continue at 1980 to
2004 levels, Upper Columbia River spring-run Chinook salmon populations are projected to
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