On July 31, 2020, EPA established Total Maximum Daily Loads (TMDLs) within the Deschutes River watershed in Washington (see Documents below).
The TMDLs are being established to replace portions of the State of Washington’s 2015 Deschutes River, Percival Creek, and Budd Inlet Tributaries TMDLs that EPA partially disapproved in June 2018.
EPA’s TMDLs use the Washington Department of Ecology’s original water quality model and data, while calculating new loadings to ensure compliance with Clean Water Act requirements and protection of the water quality standards in Washington.
New TMDLs were developed for sediment, bacteria, dissolved oxygen, pH, and temperature.
EPA accepted public comments on the TMDLs from August 7 through October 7.
After considering comments, EPA may make modifications, as appropriate, and then transmit the TMDLs to the Washington Department of Ecology to incorporate into its current water quality management plan.
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Deschutes River TMDLs (PDF)(103 pp, 1 MB,
July 31, 2020)
TMDLs for sediment, bacteria, dissolved oxygen, pH, and temperature in the Deschutes River, its tributaries, and tributaries to Budd Inlet.
Appendix A: Crosswalk Between Washington’s 2010 and 2012 303(d) Lists (PDF)(3 pp, 250 K)
Table showing connection between the State of Washington’s 2012 impaired water listings (used in EPA's Deschutes River TMDLs) and their 2010 impaired water listings (used in Ecology’s 2015 Deschutes River TMDLs).
Appendix B: Capitol Lake Designated Use Evaluation (PDF)(3 pp, 162 K)
EPA's determination of the applicable aquatic life designated use for Capitol Lake.
Appendix C: Deschutes River Find Sediment TMDL Technical Analysis (PDF)(36 pp, 1 MB)
Analysis of key sources of sediment to the impaired segment of the Deschutes River.
Appendix D: Deschutes River Bacteria TMDLs Technical Analysis (PDF)(64 pp, 2 MB)
Analysis of key sources of bacteria to the impaired tributaries of the Deschutes River and Budd Inlet.
Appendix E: Deschutes River Mainstem Dissolved Oxygen TMDLs Technical Analysis (PDF)(66 pp, 1 MB)
Analysis of key sources of dissolved oxygen to the mainstem of the Deschutes River in Washington.
Appendix F: Deschutes River Tributaries TMDLs Technical Analysis (PDF)(90 pp, 3 MB)
Analysis of key sources of temperature, dissolved oxygen, and pH to nine tributaries in the Deschutes River watershed.