3.0 Affected Environment - Knik Arm Bridge and Toll Authority

Knik Arm Crossing DraftFinal EIS
Affected Environment
Municipality, and ADOT&PF are drafting the new permit and conditions. In the interim, the
original permit is in effect.
In the vicinity of the POA, a number of nonpoint source inputs of pollution have been
identified. The POA is operated under an NPDES permit (AK-05255-8) developed for the
Municipality. POA uses specific pollution prevention measures during construction and
operation and follows a stormwater management program that includes monitoring. POA is
currently coordinating with USEPA for a site-specific NPDES permit (Anchorage Port
Expansion Team [APET] 2005). There are four major stormwater drains on POA’s property:
North TOTE (Totem Ocean Trailer Express Inc.), TOTE, Horizon/Cherry Hill, and Tesoro
systems. The Horizon/Cherry Hill drainage system provides storm runoff for most of
Elmendorf and drains through the POA on its way to Knik Arm (APET 2005).
3.8.2 Wetlands
EO 11990, “Protection of Wetlands,” and Section 404 of the Clean Water Act require FHWA
to avoid and minimize adverse effects on wetlands. Implementation of the proposed KAC
project must avoid harming wetlands unless there is no practicable alternative. If it must be
located in wetlands, the proposed project must employ all possible measures to minimize
adverse effects on wetlands. The regulatory definition of wetlands is “those areas that are
inundated or saturated by surface or ground water at a frequency and duration sufficient to
support, and that under normal circumstances do support, a prevalence of vegetation typically
adapted for life in saturated soil conditions” (33 C.F.R. § 328.3[b]). Note that this narrow
definition does not include unvegetated water bodies; those are described in Sections 3.8.1
and 3.8.7.1.
The Cook Inlet region has a transitional maritime-continental climate, and wetlands are
common in the region. The cool climate, nearly-level topography, and glacial deposits
characteristic of the region create conditions that promote the formation of abundant
wetlands. Figure 3.54 shows the locations of wetlands, water bodies, and uplands
(nonwetland) in the general Study Area, as mapped by the National Wetland Inventory.
Identification of wetlands within most of the Study corridor was based on field surveys
conducted by Study Team biologists in September and October 2005 (KABATA 2006q). For
part of the Study Area located on Elmendorf lands—to which the Study Team could not gain
access—an existing report (MOA, DEDP, and HDR 1991) and file notes from a past
investigation were used to delineate and describe the wetlands. The Study Team identified
wetland boundaries within an approximately 300-foot-wide corridor along each alternative,
classified wetlands according to the system of Cowardin et al. (1979), and considered how
those wetlands function within the natural environment. The wetland types in this “direct
effects Study Area” are described below.
A wetland’s ecological functions and social values depend on many variables, such as its
topographic and geomorphic setting; how, when, and from what sources it receives water and
how the water leaves the wetland; its vegetation structure and plant species; its macro-
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