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Biological Assessment Preparation for Transportation Projects - Advanced Training Manual
Part 1 - General Information for BA Authors
Part 2 - Guidance on Specific BA Topics
Part 3 - Additional Resources for BA Authors
Species Habitat Assessment and Effect Determination Guidance
The marbled murrelet nesting season in Washington is defined as the period from April 1 to September 23. USFWS typically requires the limited operating period (LOP) of two hours after sunrise to two hours before sunset to facilitate murrelet protection during the nesting season.
The USFWS definition of marbled murrelet nesting habitat is based on the presence of potential nest platforms. A site is considered to have suitable nesting habitat if a platform tree is within a minimum 5-acre contiguous coniferous-dominated stand within the project analysis area, has trees that are greater than or equal to 15 inches dbh, and has any platform that is a minimum of 4 inches wide a minimum of 33 feet above the ground. Work within or adjacent to marbled murrelet habitat during the nesting season may only occur during the LOP - two hours after sunrise to two hours before sunset.
In 2015, the USFWS issued a programmatic Biological Opinion (BO) for WSDOT activities. The BO establishes harassment/injury distances for noise-generating activities specific to marbled murrelets that replaces the 92 dBA threshold with the distance threshold. The standard threshold distances described in the BO can be used as a tool to assist the biologist in making effect determinations on typical transportation projects in Washington State.
Northern Spotted Owl
In 2015, the USFWS issued a programmatic Biological Opinion for WSDOT activities. The BO establishes harassment/injury distances for noise-generating activities specific to northern spotted owls that replaces the 92 dBA threshold with the distance threshold. The standard threshold distances described in the BO can be used as a tool to assist the biologist in making effect determinations on typical transportation projects in Washington State.
Oregon Spotted Frog
In 2015, the USFWS issued a programmatic Biological Opinion for WSDOT activities. The BO includes habitat suitability assessment guidance for Oregon spotted frog. The guidance provided in the BO can be used as a tool to assist the biologist in making Oregon spotted frog effect determinations on typical transportation projects in Washington State.
Listed Plants Consultations
WSDOT has developed this brief guidance (pdf 27 kb) to facilitate consultations related to listed plants. For help on identification of plant species and their habitats, the Washington State Department of Natural Resources' Natural Heritage Program and the Spokane District of the USDI Bureau of Land Management prepared a Field Guide to Selected Rare Plants of Washington.
Marine Mammal ESA Consultations
The National Marine Fisheries Service Marine Mammals Section 7 Consultation tools explain the relationship between the Endangered Species Act and the Marine Mammal Protection Act, effects of noise on marine mammals, sound threshold guidance, and other related topics. In 2016, NMFS introduced revised acoustical technical guidance.
On February 16, 2009, the Federal Highway Administration (FHWA), National Marine Fisheries Service (NMFS), United States Fish & Wildlife Service (USFWS) and the Washington State Department of Transportation (WSDOT) signed a Memorandum of Agreement (MOA) (pdf 130 kb) committing these four agencies to use a common method for analyzing the effects of stormwater on Endangered Species Act (ESA)-listed fish species. The method includes the Western Washington Highway Runoff Dilution and Loading Stormwater Model (HI-RUN Model), its user guide, and accompanying stormwater assessment guidance that is posted below. A Stormwater Impact Assessment Chapter has been incorporated into Part 3 of the WSDOT Biological Assessment Preparation for Transportation, Advanced Training Manual.
The approach is required in all biological assessments submitted by WSDOT or WSDOT Local Programs.
Note that there is a separate assessment process for Eastern Washington that does not involve the use of the HI-RUN model. Also to Note, the HI-RUN Model User's Guide and Stormwater Chapter were all updates in January 2011. Be sure you are using the most recent version.
Eastern Washington Stormwater Guidance
Western Washington Stormwater Assessment Guidance
The HI-RUN Model should only be used for stormwater analysis associated with biological assessments, and should not be used as a design tool.
Examples for Using the HI-RUN Model
Endangered Species Act Stormwater Design Checklist for Western Washington (doc 162 kb) - January 2010
*Please download to your computer prior to use. Please contact Marion Carey, if you encounter problems or errors when using the HI-RUN Model.
Programmatic Stormwater Monitoring Approach
This approach focuses on utilizing the WSDOT NPDES permit monitoring requirements to meet stormwater monitoring needs rather than monitoring individual projects. The compiled data will be used to improve the accuracy and reliability of the current stormwater models. FHWA-funded local agency projects that are similar in scope to WSDOT projects and meet or exceed the requirements of the Highway Runoff Manual for stormwater treatment may also be able to utilize this approach.
Indirect Effects Stormwater Runoff Analytical Method
On April 14, 2011, WSDOT, FHWA, NOAA Fisheries , USFWS and WSDOT signed a MOA committing these four agencies to use the Indirect Effects Stormwater Runoff Analytical Method in consultations which have development identified as in indirect effect of a transportation project. This analytical method is intended to evaluate water quality impacts associated with stormwater runoff from development identified as an indirect effect of transportation projects.
Noise Assessment Guidance
The tables below provide summary information on marine mammal, fish, and marbled murrelet injury and disturbance thresholds for impulsive and continuous underwater sound, and estimated auditory bandwidths (estimated hearing frequency ranges) for marine mammals and fish.
On November 19, 2013, WSDOT hosted a USFWS presentation that introduced marbled murrelet in-air noise masking guidance for marine water pile driving projects. The USFWS is using this guidance in marine pile driving consultations.
USFWS has created an excel spreadsheet that assists in calculating distances to thresholds.
Pile Driving Information
The tables below provide information on the typical number of pile strikes for steel piles, peak sound pressure levels and sound exposure levels for various sizes and types of piles. The data in these tables can be used to estimate sound pressure and cumulative sound exposure levels (SELcum) for various pile diameters and types. WSDOT Pile driving monitoring reports can help with site specific information for projects in the same or similar areas. The link to the CalTrans Pile Driving Compendium is also provided for comparison.
Additional Acoustical Resources
Terrestrial Noise Assessment
Use the information in Chapter 7 of the BA Preparation for Transportation Projects Advance Training manual to help determine the appropriate decibel levels for ambient noise, traffic noise and construction noise.