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King County is developing tools to help determine the most effective actions we can take to improve water quality.

We rely on clean water  for our health and the health of our environment, and we are committed to investing billions of dollars in water quality improvements in the next decade.  But how do we strategically prioritize our work to deliver the best outcomes for our investments?  To help answer these questions, we are building a toolkit from the latest scientific information that can evaluate the water quality benefits of potential actions.

The Water Quality Benefits Evaluation (WQBE) Toolkit will include:

  • Pollutant loading models, which estimate pollutant loads for major King County waterbodies taking into account major point and non-point sources.
  • System for Urban Stormwater Treatment and Analysis Integration (SUSTAIN) models, which identify cost-effective combinations of potential water quality projects and programs for reduction of pollutant loads or stormwater volumes.
  • Qualitative causal models, which define relationships between potential water quality projects and programs and a suite of ecological/human health endpoints (southern resident orca and Chinook salmon populations, toxics in fish, fecal contamination at shellfish beds, and algal toxins and fecal contamination at swimming beaches).

Questions? View Frequently Asked Questions

Water Quality Benefits Evaluation (WQBE) Toolkit components

Water Quality Benefits Evaluation Toolkit components flow

Tools

Pollutant loading models

Models will be used to estimate baseline pollutant loads to receiving waterbodies.

Sustain models

"System for Urban Stormwater Treatment and Analysis Integration" (SUSTAIN) models will be used to identify cost-effective combinations of potential water quality actions for reduction of pollutant loads or stormwater volumes. Output from the SUSTAIN models are cost-effectiveness curves showing the cost ($) and pollution-reduction (delta) effectiveness relationship across a range of actions.

Causal Models

Qualitiative models will be used to evaluate the potential benefit to the following ecological/human health endpoints:

  • Shellfish harvesting
  • Swimming beaches
  • Recreational fishing
  • Southern resident orca
  • Chinook salmon

Evaluation inputs and outputs

Actions

Actions are individual structural best management practices or activities to improve water quality. Examples include:

  • Bioretention
  • Drywell
  • Permeable pavement
  • Cistern
  • Wetvault

Package

A package is a point on a SUSTAIN cost-effectiveness curve that identifies a specific combinatino of actions. These can be selected to identify a cost-effective suite of actions.

Outputs

  • Cost
  • Pollutant reduction
  • Potential benefit to endpoints

Relationships

Pollutant loading models and actions are inputs to the SUSTAIN models. The SUSTAIN Models are the input to a package.

A package is an input to causal models and causal models and a package together produce outputs of cost, pollutant reduction and potential benefit to endpoints.

Why is King County developing the WQBE Toolkit?

The WQBE Toolkit will provide transparent, consistent methods for evaluating benefits of water quality projects and programs, such as a roadway stormwater treatment program or a rain garden installation.

WQBE will help water quality planners estimate the potential benefits to ecological and human health including open swimming beaches, safe fish and shellfish consumption, Chinook salmon populations, and the Southern Resident orca population from different water quality projects and programs.

Watch a short presentation about the project!

Learn more and tell us what you think!

King County is asking for feedback from our partners to improve the toolkit so that it can more effectively support our collective work in the region. Specifically, we would like to know the following:

  • Help identify any gaps to ensure we produce a robust Toolkit to inform King County planning efforts.
  • Hear whether there is interest in using information from the Toolkit for your work.
  • Flag any additions or improvements that could be incorporated in this phase of modeling or in future efforts. 

To learn more about the models, please visit our model-specific input sites:

Sign up for the WQBE mailing list to receive updates on project development and future opportunities to give input.

WQBE Toolkit milestones

WQBE model timeline

Pollutant loading model timelines

Model inputs

  • May - formal peer review
  • May - webinar and feedback opportunity

Watershed model calibration and report

  • August - formal peer review
  • September - webinar and feedback opportunity

SUSTAIN model timelines

Model inputs

  • June - formal peer review
  • June - webinar and feedback opportunity

Model outputs and report

  • November - webinar and feedback opportunity

Pollutant loading model timelines

Swimming beaches

  • April - formal peer review
  • May - webinar and feedback opportunity

Shellfish

  • April - formal peer review
  • May - webinar and feedback opportunity

Orcas

  • April - formal peer review
  • May - webinar and feedback opportunity

Edible fish

  • July - formal peer review
  • September- webinar and feedback opportunity

Chinook - WRIA 8 and 9

  • August - formal peer review
  • September- webinar and feedback opportunity

Model outputs and report

  • November - webinar and feedback opportunity

To learn more, please contact the project manager: Carly Greyell.

King County Executive
Dow Constantine
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