Water quality assessment & 303(d) list

Prior to beginning the current assessment, we completed a comprehensive update of our water quality assessment policy (Policy 1-11) from 2016 to 2018. We then conducted a call for data in 2018, where we received 116 million pieces of data collected between 2006 and 2017. Due to the large volume of data that are available for Washington, we developed new data tools to automate much of our assessment process. The development and testing of these new automation tools was completed in Spring 2020. Data analysis began soon after the tool development. We held a public review of our draft assessment from April to June 2021. The candidate water quality assessment was submitted to EPA on Aug. 31, 2021. EPA issued a partial approval of our candidate assessment on June 8, 2022, and their final approval on Aug. 26, 2022.

To develop the next assessment, we first need to review and update our water quality assessment policy (Policy 1-11). The purpose of the update is to provide additional and clarifying information in select sections of the policy, based on comments and questions we have received. 

The public comment period was open Nov. 7, 2022 – Jan. 6, 2023. The proposed changes are outlined in two documents.

• New freshwater harmful algae bloom methodology — A new methodology for evaluating the health of the recreational uses in waterbodies on algae bloom characteristics, toxicity data, and local public health jurisdiction recreational advisory information.
• Non-substantial edits — These minor edits provide additional information and clarity on our assessment process. Also included is a note on the temporary suspension of the natural-conditions methodology.

2022 Water Quality Assessment call for data, to help us understand the condition of state water bodies, was open July 7 through Sept. 30, 2022. For this assessment we are analyzing data and information collected between Jan. 1, 2012 and Dec. 31, 2021. 

Water quality data was submitted to Ecology's Environmental Information Management (EIM) database. Narrative information and studies, such as published research and peer-reviewed reports, were submitted directly to Water Quality Assessment staff at 303d@ecy.wa.gov.

The next step is to compile and assess water quality data from Washington’s rivers, streams, lakes and marine waters. Under the guidance of Policy 1-11, we will evaluate the data and determine where Washington’s waters designated uses are impaired. We anticipate a draft list of impaired waters for review by early 2024.

Once we update the updated Policy 1-11, we will use it to evaluate the data quality and review Washington's water bodies to determine where designated uses are impaired. The result is the draft revised water quality assessment. We expect data analysis will be completed by the end of 2023.

We expect to hold a public comment period for the next Water Quality Assessment in early 2024. The public review period generally lasts 60 days and is an opportunity for stakeholders and Tribes to provide comments on draft assessment results. During the review period we plan to host a workshop to walk through the assessment process, key changes in the assessment, assessment results, and provide a demonstration of how to use review tools and submit comments.

Following public review, we will make modifications to the Water Quality Assessment, provide a detailed response to public comments, and submit the candidate Water Quality Assessment to EPA. EPA has 30 days from the time we submit the assessment to take action. Once approved, the candidate Water Quality Assessment will become the new, approved Water Quality Assessment for Clean Water Act regulatory purposes. We will then begin the whole process again starting with reviewing Policy 1-11 and announce a call for data for the next assessment cycle.

Category 1 means a water body meets the state water quality standards. Being placed in this category does not necessarily mean that a water body is free of all pollutants.

Most water quality monitoring is designed to detect a specific array of pollutants, so placement in this category means that the water body met standards for all the pollutants for which it was tested. Specific information about the monitoring results may be found in the individual listings.

Water bodies in this category have some evidence of a water quality problem, but not enough to show persistent impairment. These are water bodies that we want to continue to test.

There are several reasons why a water body would be placed in this category. A water body might have pollution levels that are not quite high enough to violate the water quality standards. Or there may not have been enough violations to categorize it as impaired according to our listing policy.

According to Policy 1-11, Category 3 water bodies have insufficient data to place them into any of the other categories.

Category 4 means water bodies that have impairment problems are being resolved in one of three ways:

• Category 4a — already has an EPA-approved TMDL plan in place and implemented.
• Category 4b — has a pollution control program, similar to a TMDL plan, that is expected to solve the pollution problems.
• Category 4c — is impaired by causes that cannot be addressed through a TMDL plan. Impairments in these water bodies include low water flow, stream channelization, and dams. These problems, while not pollutants, require complex solutions to help restore water bodies to more natural conditions.

Water quality assessment Category 4b

We recognize that communities do not have to wait for a formal TMDL planning process to begin improving water quality. They can take the initiative to clean up polluted water. Because these efforts are locally controlled, there is an opportunity to reduce overall costs, and the communities can exert greater control over the cleanup process.

Category 4b is intended for water bodies with a pollution control program in place that is expected to solve the pollution problems. While pollution control programs are not TMDLs they must have many of the same features. There must also be some legal or financial guarantee that the program will be implemented.

To be placed in the "has a pollution control project" category, the pollution control project must meet all of the following criteria:

• Be problem-specific and water body-specific
• Have reasonable time limits established for correcting the specific problem, including load reduction or interim targets, when appropriate
• Have a monitoring component to evaluate effectiveness
• Have adaptive management built into the plan to allow for course corrections, if necessary
• Have enforceable pollution controls or actions stringent enough to attain the water quality standard or standards
• Be feasible, with enforceable legal or financial guarantees that implementation will occur
• Be actively and successfully implemented and show progress on water quality improvements in accordance with the plan

In addition to the conditions above, the project is more likely to gain approval if the following elements are included:

• A description of management measures
• An implementation schedule and measurable milestones
• A description of criteria that are used to determine loading reductions achieved over time
• An information/education component

This is the list of impaired water bodies traditionally known as the 303(d) list. Starting with the 2004 Water Quality Assessment, Washington’s 303(d) list of polluted waters were placed under category 5 in the approved assessment. Total Maximum Daily Loads (TMDLs) or other approved water quality improvement projects are required for the water bodies in this category.

If a water body is in this category it means that we have data showing that the water quality standards have been violated for one or more pollutants, and there is no TMDL — or pollution control program — in place.