Discharge Types

Category 1

A spill of any volume of sewage from or caused by a sanitary sewer system regulated under the General Order that results in a discharge to:

• A surface water, including a surface water body that contains no flow or volume of water; or
• A drainage conveyance system that discharges to surface waters when the sewage is not fully captured and returned to the sanitary sewer system or disposed of properly.

Any spill volume not recovered from a drainage conveyance system is considered a discharge to surface water, unless the drainage conveyance system discharges to a dedicated stormwater infiltration basin or facility.

Category 2

A spill of 1,000 gallons or greater, from or caused by a sanitary sewer system regulated under the General Order that does not discharge to a surface water.
A spill of 1,000 gallons or greater that spills out of a lateral but is caused by a failure or blockage in the main lines of the sanitary sewer system is a Category 2 spill.

Category 3

A spill of equal to or greater than 50 gallons and less than 1,000 gallons, from or caused by a sanitary sewer system regulated under the General Order that does not discharge to a surface water.
A spill of equal to or greater than 50 gallons and less than 1,000 gallons, that spills out of a lateral but is caused by a failure or blockage in the main lines of the sanitary sewer system is a Category 3 spill.
Note: Spills of less than 50 gallons and that were reported in accordance with the 2006 General Order are Category 3 spills and display on this map.

Category 4 Spill (not displayed on this map)

A spill of less than 50 gallons, from or caused by a sanitary sewer system regulated under this General Order that does not discharge to a surface water.
A spill of less than 50 gallons that spills out of a lateral but is caused by a failure or blockage in the main lines of the sanitary sewer system is a Category 4 spill.

Note: Category 4 spill is a new spill category in Order 2022-0103-DWQ with the goal of decreasing reporting frequency for smaller spills of less than 50 gallons.

Category 4 Spills and spills from Enrollee owned/operated laterals that are caused by a failure or blockage in the lateral and that do not discharge to a surface water, are not shown on the incident map due to the annual reporting requirements for these types of spills.