About NPDES
- Permit Basics
- State Program Information
- Permit Limits
- Program Management and Oversight
- NPDES Regulatory History
- Other Federal Laws that Apply to the NPDES Permit Program
Overview
Types of Permits
An NPDES permit is typically a license for a facility to discharge a specified amount of a pollutant into a receiving water under certain conditions. Permits may also authorize facilities to process, incinerate, landfill, or beneficially use sewage sludge. The two basic types of NPDES permits issued are individual and general permits.
- An individual permit is a permit specifically tailored to an individual facility. Once a facility submits the appropriate application(s), the permitting authority develops a permit for that particular facility based on the information contained in the permit application (e.g., type of activity, nature of discharge, receiving water quality). The authority issues the permit to the facility for a specific time period (not to exceed five years) with a requirement that the facility reapply prior to the expiration date.
- A general permit covers a group of dischargers with similar qualities within a given geographical location. General permits may offer a cost-effective option for permitting agencies because of the large number of facilities that can be covered under a single permit.
Additional Resources
Public Participation in the NPDES Permit Issuance Process (pdf) - Overview of the NPDES permitting process, highlighting opportunities for public involvement.
Primer for Municipal Wastewater Treatment Systems (pdf) - Overview of municipal processes used to treat domestic wastewater before discharge to the nation's waters.
Clean Water Act Analytical Methods - More information on laboratory analytical methods and test procedures that are used to analyze the chemical, physical, and biological components of wastewater and other environmental samples that are required by the Clean Water Act (CWA).