Puyallup River Watershed Management and Restoration Initiative

Evaluation by the use of Ecological Risk Assessment of the Implementation of Low Impact Development in the Puyallup River Watershed

Funding by the Bullitt Foundation

In cooperation with Washington State University-Puyallup (WSU-P) and the University of Washington-Tacoma (UW-T) and the Washington Stormwater Center.

Points of Contact

Institute of Environmental Toxicology

Wayne G. Landis, Huxley College WWU wayne.landis@wwu.edu

April Markiewicz, Huxley College WWU. april.markiewicz@wwu.edu

Washington Stormwater Center

John D. Stark WSU-P starkj@wsu.edu

Joel Baker UW-T jebaker@uw.edu

A pdf version of a slide show describing in more detail the risk assessment process can be downloaded here.

 

Introduction

The purpose of the project is to improve the ability of cities, counties and other jurisdictions to effectively participate in the cleanup and ongoing management of Puget Sound. The proposed project is an interdisciplinary collaboration between leading scientists at Washington State University – Puyallup (WSU-P), the University of Washington – Tacoma (UW-T) and Western Washington University (WWU).  The project also will include a variety of other active partners who are working on various salmon, water quality and low impact development (LID) projects that include the Puyallup Tribe, NOAA, the Cities of Puyallup, and Tacoma.

Background

Stormwater and other sources of non-point runoff are the largest threat to Puget Sound water quality, transporting large quantities of nutrients, pathogens, and toxic chemicals into the Sound and its tributaries. As population continues to grow, the impact of stormwater will increase.  Low impact development is a promising family of engineering controls that enhance infiltration of rainwater and improves the quality and reduces the quantity of stormwater. While the efficacy of individual stormwater controls installed at specific locations is commonly evaluated, we lack the tools to systematically quantify the benefits of LID at the watershed scale.

Objective

Simply stated, the primary objective of this program is to develop and demonstrate a risk-based management tool to address the question “What watershed scale management plans that implement low impact development LID strategies will reduce nonpoint runoff inputs enough to meet the goals of Puget Sound restoration?’

Methodology

The restoration of Puget Sound and its watersheds is dependent upon the knowledge and expertise to create effective plans to manage and to reduce the impacts of runoff.  The project partners propose to use the Puyallup River Watershed (PRW) as a representative model for all of Puget Sound watersheds.  Specifically, the partners will take advantage of the already constructed low impact development research facility at WSU-P, the analytical chemistry capabilities of UW-T and the risk based watershed and coastal modeling techniques developed at WWU’s Institute of Environmental Toxicology at Huxley College of the Environment.  The findings from the study will be used to create a model for stormwater management for the entire Puget Sound region, from Bellingham to Olympia.

The strategy is two-fold: 

1. The project employs a spatially-explicit risk analysis model, informed with climate change variables, field chemistry and toxicology studies in the PRW and explores how LID technologies should be employed across the Puget Sound.  The PRW is significant as a representative Puget Sound watershed in that it supports eight species of anadromous fishes, has a number of different land uses and goes from the Cascades to the heart of the Port of Tacoma.
2. The project also incorporates increasing investment by the state to develop and create a LID stormwater center at the WSU-P campus. Current research of LID techniques will form a foundation and a component of the iterative modeling process.

There are three project steps that will be conducted by the Instittute over the next year:

1. Obtain preliminary datasets and establish a relative risk assessment model.
2. Incorporate LID research and requirements from the ongoing research at WSU-P and UW-T.
3. Update models /complete risk analysis to construct LID scenarios.

Key Outcome

The result of this three year program will be a comprehensive approach to the use of LID to reduce stormwater and nonpoint source impacts to the critical features of Puget Sound.  This methodology will be widely presented to the numerous management groups in the region, from the Puget Sound Partnership to local municipal governments.