Water quality permits

Managing wastewater and stormwater is important to protect the health of surface and groundwater. Using a system of water quality permits, we manage when, where, and how treated wastewater and stormwater enters the environment.

We also issue Section 401 water quality certifications that make sure federal agencies do not issue permits or licenses that violate state water quality standards. 

Do I need a permit?

If a municipality or commercial industry releases wastewater into state or federal waters (groundwater or surface water), they must obtain a permit.

Which permit do I need?

The permit you need depends on what is in the water you are producing (discharge characteristics) and what water source is receiving it (receiving waters).

Types of permits

State Waste Discharge permits (SWD permits) regulate discharges from:

  • Municipalities or industries to groundwater.
  • Commercial industry to a publicly owned treatment works (POTWs).
SWD permits are issued:
  • Individually or through general permit coverage.
  • Based on state groundwater quality standards or federal effluent limit guidelines for industrial discharges to a publicly owned treatment works.

National Pollutant Discharge Elimination System (NPDES) Wastewater Discharge Permits regulate direct discharges to surface water from POTWs or commercial industry. We have delegation from the EPA to write these federal permits. These permits are a requirement of the federal Clean Water Act.

We issue these permits based on state surface water quality standards, which can be more stringent than federal water quality standards. NPDES permits are issued individually or through general permit coverage.

General water quality permits

General water quality permits regulate specific categories of discharge, such as stormwater or wineries, which release treated storm/wastewater to either surface or groundwater.

Categories of general permits include:

If you do not see your industry covered by one of the general permit categories, you may need coverage under an individual discharge permit.

Individual water quality permits

We issue individual water quality permits for one specific entity where discharge characteristics are variable and do not fit a general permit category. Changes to these permits also follow a public comment process.