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WSDOT Biological Assessment Content

Photo of Peregrine Falcon
Peregrine Falcon - Photo from USDA
Forest Service

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Biological Assessments

The Endangered Species Act requires preparation of a BA for any major construction project with a federal nexus. The purpose of a BA is to evaluate the potential effects of a proposed project on listed and proposed wildlife, fish, and plant species and designated or proposed critical habitats that are likely to occur in the vicinity of the project. To ensure compliance with the ESA, some agencies, including WSDOT, prepare BAs for projects that would not be considered major construction.

The BA should use the “best available scientific and commercial information” (USFWS, NOAA Fisheries 1998). This information is used to help analyze project impacts and is the basis for the effect determination. The information used must have been evaluated by the Services and found to be acceptable. For example:

  • Appendix A of the NOAA Fisheries matrix document (NOAA Fisheries 1996) identifies key habitat elements and activities that affect them and also provides references for species under NOAA Fisheries jurisdiction
  • Status reports for species provide numerous references.
  • Services biologists can be contacted and may have additional species-specific information, including contact information for local area habitat biologists or academic experts.


Project Development and Team Assignment

Once a project need has been identified, WSDOT or the lead agency will compile a team of project engineers, environmental permit coordinators and designers to develop the project. This internal team will begin generating project concepts and designs and identifying the environmental permitting issues pertaining to the project. Generally, once the project team has 30-percent designs complete, the environmental permitting process, including ESA consultation, begins. The environmental permitting process may begin earlier or later in the project design process depending upon the specific project.

Ideally, a project biologist will be assigned to the project team early on in the design process to provide input to the design process. This may be the WSDOT regional biologist, a consultant biologist, or a biologist from ESO in Olympia.  The project biologist works with project designers and engineers to identify species of concern in the vicinity of the project, whether surveys for wildlife or plants will be required, in-water work windows, timing restrictions based on wildlife sensitive periods, and other environmental considerations and issues of special concern. 

Though consultant biologists are hired based upon their individual qualifications and expertise, the biological assessments they are contracted to produce are agency documents that must be consistent with both WSDOT and FHWA policies and practices. To this end, consultants preparing biological assessments on behalf of these agencies should think of themselves as part of the WSDOT project delivery team , striving to produce documents that are internally consistent, that accurately reflect agency policies, practices and publication styles, and that have been fully coordinated with other team members.

Some basic steps for consultants to ensure the documents they produce reflect WSDOT standards are provided below:

  • Coordinate early and often with the WSDOT project manager, project engineer and regional biologist.
  • Recognize that it is WSDOT's responsibility to define the action upon which it wishes to consult.
  • It is the consultant's responsibility to assess the impacts associated with the action as defined by WSDOT.
  • Action agency responsibilities - it is the responsibility of WSDOT, acting on behalf of FHWA, to provide an effect determination for each listed or proposed species or designated critical habitat potentially affected by a project. The consulting biologist provides a tentative effect determination for their approval.
  • Consultant's responsibility is to coordinate the effect determinations contained in a biological assessment with the WSDOT regional biologist to ensure the analysis and conclusions of the BA are consistent with other projects in the region and with current agency policies.


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Bull Trout - Photo from USDA Forest Service

Information Gathering

The information gathering process for is divided into two steps:

Species List Acquisitions

The project biologist must have a species list to prepare the biological assessment. Species lists identify listed species, proposed species, candidate species, species of concern, and proposed and designated critical habitat in defined geographic areas.

USFWS provides countywide species lists. Because they are not specific to the project area, these countywide lists often include species that do not occur in or near the action area. 

NOAA Fisheries species lists relevant for Washington state can also be obtained online. There is one list for listed salmon species (Snapshot of ESU status), a map and accompanying list for designated critical habitat for listed salmon ESUs, for marine mammals, sea turtles and other marine species in Washington State.

The project biologist generates site specific species lists by paring down county and state wide lists from NOAA Fisheries and the USFWS using WDFW Priority Habitat and Species data, WDNR Natural Heritage data, Federal Register and listing documents that summarize current and historical distributions and personal communications with local experts (tribal, WDFW, DNR, etc).

Note:  All specific site information is sensitive and confidential and should not be included in public documents or the final BA.

Project-Related Information Gathering

When gathering information related specifically to the proposed action, the project biologist must complete two steps:

  • Develop an understanding of the proposed action - which involves breaking down the proposed action into is various elements
  • Conduct a site visit.

More details on these steps are found in the Advanced Training Manual.


Impact Analysis

The impact analysis phase is divided into two tasks:

  • Analysis of Chemical, physical, and biological project effects on the environment determine the geographic extent of the project action area.
  • Analysis of Project Impacts to Species and Critical Habitats.

For projects that require formal consultations due to an adverse effect determination, the BA must address cumulative effects. However, impacts associated with cumulative effects do not influence the effect determination of the project on listed species or critical habitat.

More details on these steps are found in the Advanced Training Manual.

Reference Citations and Appendices

Additional guidance is also available for what to include in the Reference section of the BA or in the Appendices of the report.

Additional Online Resources

There are numerous online scientific resources for biologists to complete the BA.