Three Basin Rulemaking Petition

Petition to amend the Three Basin Rule

Petition contact: Aron Borok, 503-229-5050

The Oregon Department of Environmental Quality received a petition and supporting information from Marion County to amend the Three Basin Rule on Aug. 30, 2024.

The proposed rule would allow a new publicly owned treatment plant discharging to groundwater as long as the discharge meets certain requirements.

The Three Basin Rule provides additional protections beyond those usually provided by water quality standards in three watersheds that are major drinking water sources – the Clackamas, the North Santiam and the McKenzie. The Three Basin Rule prohibits new or expanded discharges to these three basins except subsurface discharges with no subsurface connection to surface waters. For more information, read the fact sheet on this petition.

Public involvement

The public comment period closed on Oct. 6, 2024 at 5 p.m.

Comments received during the public comment period will be considered in DEQ's recommendation to the Environmental Quality Commission and compiled into the staff report.

EQC action

On Nov. 21, 2024, in response to Marion County's petition, the Oregon Environmental Quality Commission voted to direct DEQ to start rulemaking proceedings to revise the Three Basin Rule to allow NPDES permits under limited circumstances consistent with the stated objectives of the rule.

The rulemaking process includes convening a rule advisory committee to develop the rules, posting draft rules for public comment, holding a publlic hearing, and taking final rules back to the commission for adoption.