WSP06003

• File Number: 8449.900
• Description: Bear Creek
• State: CO
• Basin: South Platte
• Date: 11/1/1991
• Author: City of Lakewood
• Title: Bear Creek Lake Preliminary Environmental Assessment Wetland Task Report
• Water Supply Pro - Doc Type: Publication

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ES ENGINEERING-SCIENCE

assessment (EA) to document potential environmental consequences of the action.
If the EA reveals potential significant adverse impacts, then NEP A requires a more
comprehensive and systematic assessment that summarizes the analytical findings
and makes them available for full public disclosure as an environmental impact
statement (EIS).

Regardless whether Section 404, EO 11990, or both statues apply, the Corps
would require an EA before authorizing additional water storage and operational
changes. The EA is a standard requirement preceding any significant Corps action
to ensure that the public's best interests are considered and to ensure compliance
with regulatory guidelines and requirements. The EA findings would identify the
nature and magnitude of potential significant environmental impacts. These
findings would De considered by the Corps along with other information to
determine whether to authorize the proposed activity or to require more intensive
analysis of project implications. The costs and responsibility for preparing the EA
and other environmental and/or project documents typically are the project's
sponsor(s).

If EA findings suggest significant adverse impacts would be likely, then the Corps
would probably require preparation of an EIS to address public concerns and to
fully disclose the relative advantages and disadvantages of the proposed project and
its alternatives. Further discussion of this process and the typical range of costs for
preparing an EA and EIS are provided in the following section.

Mitigation Requirements

Each water storage scenario, except Scenario A, would produce losses of
jurisdictional wetlands and riparian areas. Because both resource types are of
significant interest to the Corps, it is probable that the Corps would require
mitigation for these losses. In recognition of the important roles riparian areas play
in the Omaha District, the Corps considers and manages riparian areas in a manner
that is essentially analogous to jurisdictional wetlands (Gorton, 1991). The EPA,
FWS, and CDOW also consider wetlands and riparian areas to be of high interest
and environmental value. Through interagency review and coordination processes
for a Section 404 permit, EA, or EIS, these agencies would strongly support
mitigation for unavoidable wetland and riparian area losses. The existing qualities
of the Bear Creek and Turkey Creek riparian and wetland corridors would probably
require mitigation measures as a condition of project approval.

The Corps and EPA established an MOA addressing guidelines for determining
the type and level of wetland mitigation necessary to demonstrate compliance with
Section 404 (b)(I) guidelines (Appendix 2). Although the MOA guidelines are
applicable to all discharges of dredged or fill material, they focus on individual
permit applications. The purposes of the MOA guidelines are to help attain the
national goal of no net loss of wetland (or other U.S. waters) values and functions
and to provide guidance for determining compliance with requirements of the
Section 404 (b)(I) guidelines. The corrected version of the MOA is listed in 12
March 1990, Federal Register (Volume 55, No. 48, pages 9210-9213). The MOA
also acknowledges that the no-net-loss goal may not be achieved in each and every

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