Stormwater Action Monitoring (SAM)

Program Description

The Stormwater Action Monitoring (SAM) is a collaborative, regional stormwater monitoring program that is funded by the City of Arlington, the ports of Seattle and Tacoma, the Washington State Department of Transportation and over 90 other Western Washington cities and counties. SAM’s goal is to improve stormwater management, reduce pollution, improve water quality, and reduce flooding. The group does this by measuring stormwater impacts on the environment and evaluating the effectiveness of stormwater management actions.

Why is SAM Important 

Stormwater pollution is one of the biggest risks to western Washington streams, lakes, and Puget Sound water quality. Stormwater runoff from developed areas drains to local water bodies, where it releases pollutants, causes flooding, erodes streams, harms salmon, and closes shellfish beds. 

SAM identifies effective actions and tracks regional progress reducing pollution and flooding associated with stormwater. SAM projects are developed in an open and coordinated way. The goal is to capture a regional understanding of how management actions can lead to results. Stormwater managers, field practitioners, and policy makers can use SAM findings to improve management practices and to set project and funding priorities. 

Participating in the SAM projects that are designed to produce regionally transferable findings helps our community preserve our valuable water resources.  Smaller jurisdictions, like Arlington, do not have the capacity for such studies, however we benefit from these collective efforts.  Participating jurisdictions may also leverage SAM funds to answer relevant local questions. All permittees implement SAM findings to protect lakes, rivers, local streams, and Puget Sound.

How SAM Works

Collectively, municipal stormwater permittees in western Washington spend an estimated $250 million per year to manage stormwater and they invest about one percent of these expenditures into a pooled fund.

SAM efforts produce actionable findings in three focus areas.


The Long View 

SAM’s unique design provides flexibility to accomplish long-term results. The projects are not limited by grant program timelines or permit expiration dates.

SAM projects deliver concrete interim and final products providing useful information throughout the duration of each individual project.

Our Partners

The Stormwater Work Group (SWG), a formal stakeholder group, defines SAM annual activities. The Pooled Resources Oversight Committee (PRO-Committee), a subgroup of the SWG, oversees transparency, efficiency, and accountability of SAM expenditures. The Washington State Department of Ecology serves as the administrative entity that manages SAM funds and executes SAM contracts. State and federal agencies provide in-kind leadership and support on projects.

Annual Reports 

               2015                         2016                    2017                    2018                    2019                    2020                   2021                    2022                                               


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