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King County Ambient Monitoring Program Methods

The King County Freshwater Benthic Macroinvertebrate Sampling and Analysis Plan for annual monitoring.

Regional Puget Sound B-IBI Projects

King County staff have worked with partners in the region on projects related to benthic macroinvertebrates and stream health. Most of these projects were funded in part by WA Department of Ecology and EPA’s National Estuary Program. Links to more information about the projects are listed below.

Impact of Urban Development on Stream Macroinvertebrate Communities is Influenced by when Development Occurred

King County staff investigated if and how the timing of development in a stream basin helps explain the variation in stream macroinvertebrate communities and measures of stream health. We found that basins with the newer development had better B-IBI scores than basins with older development. This suggests actions that have been implemented to minimize effects of urban development have had some positive effects. The study results indicate that urban development is still the leading cause of degraded conditions, but the relative impact of newer development appears to be less than previous development.

Project Documents:

Impact of Forest Condition on Macroinvertebrate Communities and Biotic Integrity

King County staff investigated if and how forest conditions affect stream health. We used B-IBI scores as our measure of stream health. Our goal was to see if forest harvests impact B-IBI scores in forested basins. But it is difficult to get accurate measures of past forest harvest. Instead, this study focused on forest conditions influenced by forest harvest. We looked at different potential mechanisms and spatial scales of impact.

The results suggest that disturbed forest conditions have little influence on B-IBI scores. The influence we observed decreased as distance from the stream increased. These results apply to forested watersheds with very little residential or commercial development.

Project Documents:

The Restore and Protect Project 

King County has completed two projects related to the Puget Sound Partnership’s recovery and protection targets for B-IBI. 

The first project – Phase I - focused on developing a framework for identifying and prioritizing stream basins for restoration and protection, based in part on their B-IBI scores.

The second project – Phase II – focused on developing basin-specific restoration and protection plans for 14 Puget Sound basins.  

The Bug Seeding Project

This project aimed to jump-start the ecological recovery of several historically degraded King County streams by seeding them with a diverse community of macroinvertebrates – or “stream bugs” - from healthy streams.

The Recalibration of the Puget Lowlands B-IBI

King County worked with regional partners from 2010-2014 to enhance and standardize the Puget Lowlands benthic macroinvertebrate monitoring and analysis tools for the Puget Sound Region. This included updating and recalibrating the B-IBI scoring system, comparing field methods, and evaluating how environmental stressors affect macroinvertebrate communities.

Historic monitoring reports

B-IBI scores for streams around King County from 1994 through 2001 (Microsoft Word format)

Sampling and Analysis Plan (SAP) for new macroinvertebrate studies: Greater Lake Washington and Green-Duwamish River Watersheds Wadeable Freshwater Streams Benthic Macroinvertebrate Sampling and Analysis Plan.

2002 Report: Benthic Macroinvertebrate Study of the Greater Lake Washington and Green-Duwamish River Watersheds Year 2002 Data Analysis and 2002 Appendices.

2003 Report: Benthic Macroinvertebrate Study of the Greater Lake Washington and Green-Duwamish River Watersheds Year 2003 Data Analysis, including apendices.

For questions about information on this page, please contact Jenée Colton, Lead, Toxicology and Contaminant Assessment Group or Kate Macneale, Environmental Scientist.