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project development and operation. Direct, indirect, and cumulative effects
of the proposed action on wetlands in the development area, as well as
adjacent properties that are affected, should be considered and described.
Although the wetland fill for a golf course has apparently been omitted from
the project, the hydrologic studies requested by U.S. Fish & Wildlife Service
remain crucial to minimizing impacts to the Crescent City Marsh and the
western lily. The DEIS section on groundwater focuses on impacts related to
groundwater withdrawal, rather than changes in the inputs (in both quantity
and timing) to groundwater that are likely to occur as a result of this project.
As a result, there are no mitigations proposed to protect groundwater, which
is a serious deficiency in the DEIS and should be reexamined.
According to the Draft Management Plan for the Crescent City Marsh Wildlife
Area (CCMWA),
The CCMWA lies within a relatively small watershed of approximately 2,000
acres. Most of the watershed has a low gradient with slow moving water. The
CCMWA receives water from three small creeks (Figure 5). Two of these
drainages feed the marshes of Area 4, where the majority of the unique
botanical resources of the CCMWA occur. These creeks pass through several
culverts under Humboldt Road and Highway 101.
Standing water occurs frequently throughout much of the CCMWA during wet
winter periods. Open water occurs year round in two permanent ponds in
Areas 2 and 4. Water table measurements have been taken annually in the
North and South Marsh since 1997 (Imper & Sawyer 2002). Measurements
taken in mid to late-July between 1997 and 2001 show the water table in
these marshes ranges from 2 to 36 inches below the surface with an average
of 12.85 and 11.1 inches in the North and South Marsh, respectively. The
depth of the water table is correlated with vegetation height and species
composition; lower water table measurements correspond to taller and
woodier vegetation. Because many of the rare plants, including the western
lily, occupy only a very narrow elevation band within the marsh, even small
changes in water levels caused by increased runoff or sedimentation from
land use upstream could impact these species (Wear 2005).
Changes in the quantity and seasonality of runoff could severely impact the
western lily and other rare plants and plant communities at the Marsh.
Therefore, the hydrological analysis should focus particularly on how the
project could potentially affect the water table in the Crescent City Marsh
throughout the year. Information on existing water table levels, seasonal
changes in water table levels, site specific information on soils and geology
that affect subsurface and surface water interconnectivity, and known life
history traits of the western lily must be included in the DEIS. Without this
information, the analysis cannot ensure that direct, indirect, and cumulative