Great Salt Lake Discharge Permitting Program

General Permitting Program

The Division of Water Quality (DWQ) requires and issues Utah Pollution Discharge Elimination System (UPDES) permits to all entities that discharge pollutants from a point source to waters of the state, including discharges of domestic and industrial wastewater along with more diffuse sources like stormwater. For domestic and industrial dischargers, these permits establish allowable concentrations of pollutants and/or mass loadings in the permittee’s discharge and include monitoring requirements to ensure the resulting water quality in the discharge is sufficient to protect the applicable designated uses and is consistent with Utah’s antidegradation policy. For stormwater discharges, permits establish best management practices to ensure designated uses are protected.

Great Salt Lake (GSL) Permitting

The development of allowable concentrations/ loadings (permit limits) for lake discharges has been complicated by the lack of numeric criteria for pollutants of concern. Permit limits are based on the most stringent of:

  • Technology-based effluent limits (which includes, but is not limited to, secondary treatment standards for municipal wastewater treatment plants and/or categorical effluent limits prescribed for a given industry)
  • Numeric criteria
  • Application of the Narrative Standard

Currently, permitted discharges, whether directly to the lake or indirectly through the main rivers, fall into four major classifications:

  • Municipal wastewater treatment facilities or publicly owned treatment works (POTWs)
  • Stormwater discharges
  • Mineral extraction facility discharges
  • Other industrial facility discharges

POTWs that discharge directly to the lake have permit limits that are currently derived from secondary treatment standards, which are technology-based limits that establish the minimum national standards for municipal wastewater treatment facilities. Industrial activities such as mining and other common types of industrial dischargers (e.g., chemical manufacturing, refineries, and landfills) have permit limits that are derived from the most stringent among technology-based effluent limits, water-quality-based effluent limits, or best professional judgment.

Insufficient information currently exists to ascertain whether technology-based effluent limits (e.g., secondary treatment standards for municipal wastewater treatment facilities or POTWs) are sufficiently protective of the lake’s uses.

Because the development of GSL-specific numeric water-quality criteria for all pollutants will require significant time and resources, DWQ has implemented an interim permitting program for GSL discharges to protect the lake’s beneficial uses while developing and criteria adopted in 2016 following response to public comments. This permitting program helps ensure that GSL’s beneficial uses are protected from potentially harmful pollutants while water-quality standards are developed and adopted for the lake.

The interim permitting process includes:

  • Discharge monitoring
  • Comparison of pollutant concentrations to screening levels
  • Whole effluent toxicity (WET) testing

At this point, these requirements have been applied to all UPDES permitted discharges that discharge either directly to a portion of GSL or to immediate tributaries that also lack numeric water quality standards.