Integrated Lists of Waters & Related Reports

MassDEP is working on comprehensive statewide assessments of designated uses in the upcoming 2028 Integrated Report (IR). Designated uses are established in the Massachusetts Surface Water Quality Standards (314 CMR 4.00). Aquatic Life Use assessments are not yet completed or available for the current cycle, but they will be incorporated (along with the assessments of other designated uses) into the 2028 IR.

MassDEP plans to issue a combined draft 2024/2026 Integrated Report (IR) in Fall 2025. The 2024/2026 IR will update all watersheds and coastal drainage areas for all Assessment Units statewide for the Secondary Contact Recreation use, as well as for the following uses: Primary Contact Recreation, Aesthetics, Shellfish Harvesting, and Fish Consumption. The data range for use attainment decisions for the 2024/2026 IR will be 2011 through 2022. 

Technical Basis for a single 2024/2026 Integrated Report:

In June 2023, EPA approved the vast majority of the final 303(d) list in MassDEP’s 2022 IR, but deferred action on Secondary Contact Recreation use attainment decisions.  To address the deferred actions, MassDEP is reevaluating all readily available Escherichia coli (E. coli) and enterococci data according to updated bacteria evaluation procedures based on EPA guidance on Secondary Contact Recreation bacteria thresholds. To complete a comprehensive statewide reassessment of the Secondary Contact Recreation use (using both historical and current data), MassDEP is combining the 2024 and 2026 reporting cycles into a single 2024/2026 IR. The methodology for this comprehensive reevaluation will be described in detail in the draft 2024/2026 IR.

MassDEP submitted the proposed final 2022 IR to EPA in May 2023.  In addition to the main narrative report and related appendices (1-5), documentation of the assessment and listing decisions made for the 2022 IR was provided in individual decision summary documents for each watershed and/or coastal drainage area assessed (Appendices 6-26). Each appendix summarized the most recent assessments for each existing assessment unit in the watershed and included a table with all impairments added, removed, or changed between the 2018/2020 and 2022 reporting cycles. Data and information supporting all decisions to remove impairments were included in the decision summaries. Also, Appendix 27 provided a summary of changes from the draft to final IR.

For the 2022 IR, quality-controlled data submitted to MassDEP prior to the pre-established deadline of January 15, 2021, were considered relative to the watersheds that were assessed. Data submitted after the deadline were not considered for the 2022 IR but are being reviewed and considered for use in a subsequent cycle, dependent on the planning for future IR cycles.

On June 30, 2023, MassDEP received a partial approval letter from EPA for the 2022 IR. The letter specified 303(d) list decisions that EPA approved, in addition to decisions related to secondary contact recreation that EPA deferred approving (i.e., “deferred action” on). EPA approved the vast majority of the 303(d) list but deferred action on Secondary Contact Recreation use attainment decisions that met the following two conditions: 1) the waters were not included as impaired or threatened on the 303(d) list submitted by MassDEP, and 2) data and information pertaining to bacteria impairment status for the waters were available. EPA deferred action on these waters until EPA and MassDEP developed a consensus approach for assessing bacteria data and information for the Secondary Contact Recreation use. MassDEP coordinated with EPA on the methodology for utilizing bacteria data for Secondary Contact Use assessment to be implemented in the subsequent IR.

For a geospatial view of current and historic water quality assessment and listing decisions, open WPP’s Water Quality Data Viewer (under the Integrated List of Waters view).  This information can also be viewed using the MassMapper application (select “Regulated Areas” to access the individual data layers for the DEP Integrated List of Waters: rivers, lakes/estuaries, and watersheds) and can be downloaded at MassGIS (URL pending).