National Pollutant Discharge Elimination System Program

Helping permittees and permit writers protect water quality under changing conditions through the methods, tools, and information used to develop and implement NPDES permits and programs.

On this page:

• About the Program
• Types of Assistance
• How This Program Helps Build Resilience
• Connections to Other EPA, Federal, or Non-Governmental Efforts

About the Program

The National Pollutant Discharge Elimination System (NPDES) program authorizes point source discharges of pollutants to waters of the United States. Hundreds of thousands of facilities and operations throughout the United States currently have permits to control water pollution issued by the EPA and authorized states.

Types of Assistance

The primary assistance role of the NPDES program is to ensure the consistent and effective implementation of the program nationwide, which often requires customized types of assistance on a case-by-case or permit-by-permit basis.

Technical Assistance

The program offers various types of technical assistance, including resources for permit writers, training, and tools, along with regulatory navigation and other assistance with developing and implementing NPDES permits. Assistance is primarily provided to NPDES permitting authorities and NPDES permittees, although the program works with a wide array of stakeholders. NPDES program staff at EPA Headquarters and in each Regional Office are available to assist.

How This Program Helps Build Resilience

More intense precipitation, floods, droughts, increases in ambient water temperatures, and rising sea levels pose challenges for NPDES permittees and permit writers. Many NPDES permittees are often on the front lines of ensuring that their communities have resilient utilities in the face of these challenges. Permit writers must ensure that permits continue to be effective instruments for ensuring water quality protection and asset management. Refining the methods, tools, and information used to develop and implement NPDES permits and programs can help manage wastewater discharges to protect water quality under these changing conditions.

Information and Tools

The NPDES program identifies information and tools that may be helpful to permit writers and permittees as they implement pollution control programs in the face of climate-related challenges. For example:

• The SWToolbox was created by U.S. Geological Survey (USGS) in collaboration with EPA to assist NPDES permit writers and other practitioners with obtaining better data and methods for estimating critical stream statistics such as the 7Q10. This downloadable tool combines and enhances the functionalities of older statistical approaches (EPA’s DFLOW and USGS’s SWSTAT), directly accesses current and historical flow data from USGS gaging stations and allows users to upload their own data.
• The NPDES program also developed a companion document: Low Flow Statistics Tools—A How-To Handbook for NPDES Permit Writers, which describes how to estimate low flow statistic values in a variety of situations using free, publicly available tools.
• The NPDES Permit Writers' Clearinghouse is a searchable web-based portal containing links to permit language, templates, and other resources that are shared by permit writers in the National Pollutant Discharge Elimination System (NPDES) program. Users can search by relevant terms including “climate,” “resilience,” and others.

Permits

When the water quality objectives of an NPDES permit align with the resilience objectives of a permittee or community, a permit can support the implementation of other water management actions that create both water quality and resilience benefits (e.g., green infrastructure, asset management, stormwater management, resilience or capacity assessments). The NPDES program will continue to address and prioritize specific needs as they are identified by state, local, and other program partners.

Connections to Other EPA, Federal, or Non-Governmental Efforts

The EPA’s NPDES program works closely with state programs, which issue and provide compliance for most NPDES permits. The program also works regularly with other organizations such as the Association of Clean Water Administrators, the Water Environment Federation, the National Association of Clean Water Agencies, and many municipal and industry groups representing permitted sectors and operations. Through these collaborative networks, the NPDES program connects with a vast array of stakeholders.