Kodiak Airport Environmental Impact Statement
Alaska Department of Transportation and Public Facilities and the Federal Aviation Administration

Vigil-Agrimis, Inc. (VAI) assisted Barnard Dunkelberg & Company, the Federal Aviation Administration (FAA) and the Alaska Department of Transportation & Public Facilities (ADOT&PF) with the preparation of an Environmental Impact Statement (EIS) for proposed runway safety improvements at Kodiak Airport. Geographic constraints of the airport location presents a challenge since increasing runway safety area inevitably means placing fill in bays or near the mouths of rivers—posing a threat to seven salmon species and the endangered Steller’s eider that frequents the waters offshore. The Buskin River Estuary is also an important subsistence resource for Koniag Native Americans.
VAI was responsible for the wetland and other waters, floodplain, and freshwater quality sections of the EIS. VAI traveled to Kodiak to meet with agency and other stakeholder staff to identify the key issues regarding these subjects. Available documents were reviewed, resulting in the identification of data gaps and a thorough field investigation to collect the needed data.

VAI collected cross section data, sampled bed material for sieve analysis, and classified geomorphic reaches along the Buskin River and Devil’s Creek. Cross section data was used to develop a hydraulic model using HEC-RAS to map the 100-year and 10-year floodplains of the Buskin River in the vicinity of the airport. This model described flooding under both high- and low-tide conditions. Tidal elevations were based on local tide gauge data translated to the project vertical datum. The tidally influenced river mouth and barrier bar were identified as crucial habitat for salmonids and marine fishes. VAI staff worked closely with coastal process modelers to qualify the combination for river and marine conditions needed to overtop the bar. The results of the stream assessment, model results and water quality research were combined into a water resources technical memorandum submitted to the FAA.

VAI also completed a wetland delineation of the airport property in the EIS study area. A wetland delineation report and functional assessment were submitted to the Corps of Engineers for concurrence.
VAI is currently evaluating the effects of proposed alternatives on wetland, river, floodplain resources and fresh water quality. VAI continues to meet with resource agency staff and other stakeholders to review the EIS, as well as participate in public meetings to explain project findings and address questions.