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Water Quality Policy 1-11 Chapter 2 - Ensuring Credible Data for Water Quality Management

Publication number Date Published Date Revised
21-10-032September 2006July 2021
VIEW NOW Water Quality Policy 1-11 Chapter 2 - Ensuring Credible Data for Water Quality Management (Number of pages: 24) (Publication Size: 1153KB)

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Author(s) Water Quality Program
Description This policy describes the Quality Assurance (QA) measures, guidance, regulations, and existing policies that help ensure the credibility of data and other information used in agency actions based on the quality of state surface waters. Agency actions include (1) determinations of whether a surface water is supporting its designated use, such as the 303(d) and 305(b) assessment processes, (2) establishment of a Total Maximum Daily Load (TMDL) and the associated load allocations and wasteload allocations, and (3) revisions to water quality standards. This policy is required by the Water Quality Data Act (WQDA) codified in RCW 90.48.570 through 90.48.590.
NOTES Minor revisions made to original September 2006 policy document to fix outdated web links and make changes for accessibility. No substantive revisions were made.
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Keywords 303(d), water quality, quality, water quality standards, TMDL, freshwater, freshwater quality monitoring, marine water quality monitoring
WEB PAGE Assessment policy 1-11 - Washington State Department of Ecology

Water Quality Program Policy 1-11 Chapter 1: Washington's Water Quality Assessment Listing Methodology to Meet Clean Water Act Requirements

Water Quality Program Policy 1-11 Chapter 1: Response to Comments July 2020

Water Quality Program Policy 1-11 Chapter 1: October 2018 Public Review Response to Comments