The following TMDLs are adopted by EQC by reference in this rule on the dates indicated. The TMDL documents and supporting information for TMDLs adopted as rule or issued by order are available on DEQ’s website.

1. (1) Upper Yaquina River Watershed, USGS watershed of the Northern Oregon Coastal Basin (HUC 1710020401):

   1. (a) TMDL: bacteria and dissolved oxygen, September 14, 2023
   2. (b) WQMP: bacteria and dissolved oxygen, September 14, 2023

2. (2) Powder River Basin, USGS Subbasin of the Middle Snake-Powder Basin (HUC 170502), including the Powder River Subbasin (HUC 17050203), Burnt River Subbasin (HUC 17050202) and Brownlee Subbasin (HUC 17050201):

   1. (a) TMDL: bacteria for E. coli, May 23, 2024
   2. (b) WQMP: bacteria for E. coli, May 23, 2024

3. (3) Willamette Subbasins – Ten subbasins within the Willamette Basin (HUC 170900), including the Middle Fork Willamette Subbasin (HUC 17090001), Coast Fork Willamette Subbasin (HUC 17090002), Upper Willamette Subbasin (HUC 17090003), McKenzie Subbasin (HUC 17090004), North Santiam Subbasin (HUC 17090005), South Santiam Subbasin (HUC 17090006), Middle Willamette Subbasin (HUC 17090007), Molalla-Pudding Subbasin (HUC 17090009), Clackamas Subbasin (HUC 17090011), and Lower Willamette Subbasin (HUC 17090012).

   1. (a) TMDL: temperature, May 8, 2025
   2. (b) WQMP: temperature, May 8, 2025

4. (4) Lower Columbia-Sandy Subbasin (HUC 17080001), within the USGS Lower Columbia Basin (HUC 170800)

   1. (a) TMDL: temperature, August 6, 2024
   2. (b) WQMP: temperature, August 6, 2024

Statutory/Other Authority

ORS 468.020, 468.065, 468B.030 & 468B.035

Statutes/Other Implemented

ORS 468B.020 & 468B.110

History

DEQ 12-2025, amend filed 05/09/2025, effective 05/09/2025
DEQ 11-2025, amend filed 05/08/2025, effective 05/08/2025
DEQ 13-2024, amend filed 08/06/2024, effective 08/06/2024
DEQ 9-2024, amend filed 05/28/2024, effective 05/28/2024
DEQ 14-2023, adopt filed 09/15/2023, effective 09/15/2023