Final Environmental Impact Report - Whittier Bridge/I-95 ...

EEA#14427
DEIR Certificate
December 30, 2011
REVIEW OF THE DEIR
Project Description
The Draft EIR includes a detailed project description, project plans, illustrative
renderings, analysis of baseline environmental conditions, an alternatives analysis, a greenhouse
gas (GHG) analysis, an updated and revised traffic analysis and associated plans, an air quality
analysis, identification of wetland resources and potential impacts, a stormwater management
plan, a summary of environmental site assessments, a noise analysis and environmental
mitigation commitments, Section 61 Findings, a list of required permits and regulatory review,
and responses to comments received on the ENF.
Alternatives Analysis
As required by the Scope, the alternatives analysis identifies, describes and compares
potential impacts for the following alternatives: No Build; seven Merrimack River Crossing
Alternatives; and five Highway Widening Alternatives. The DEIR also evaluated four bridge
design alternatives and alternative alignments for the proposed shared-use path.
The No Build, River Crossing and Highway Widening Alternatives were screened by the
following engineering and environmental criteria: purpose and need; highway configuration;
bridge configuration; traffic; right-of-way (ROW); cost; construction; schedule; and
environmental. The DEIR presents the analysis in a tabular format (Table 3-11) with supporting
narrative and conceptual site plans. Following a thorough analysis of the alternatives, the
combination of the New 8-Lane East Bridge River Crossing Alternative and the Inside Widening
Alternative (Northern Terminus to Route 286) was identified as the Preferred Alternative. The
analysis indicates that this Preferred Alternative best met the screening criteria of purpose and
need, as well as highway configuration, traffic (capacity), bridge configuration (design
standards, structural safety, maintenance and inspection, and life cycle/costs), construction
(constructability), ROW, and environmental. The Preferred Alternative will provide a new
bridge to the east of the existing bridge, to which all traffic will be temporarily relocated. The
existing Whittier Bridge would then be demolished, and second new bridge will be constructed
in its place. When construction is completed, the two new bridges will be configured to carry
four lanes of traffic in each direction. Widening for the Preferred Alternative will begin at the
Route 110 interchange and end at the Route 286 interchange and will include widening in both
directions within the existing median.
The alternatives analysis does not identify opportunities to minimize impervious area
within the project corridor. The DEIR indicates that certain factors, such as land alteration,
impervious area and parking were not included in the analysis as these factors were not deemed
relevant to the screening of potential alternatives. The DEIR claims that minimization of
impervious area for the new Merrimack River Crossing and 1-95 Widening Alternatives is
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