Watershed-Based National Pollutant Discharge Elimination System (NPDES) Permitting Implementation Guidance

摘要

The purpose of this guidance is to describe the concept of and the process for watershed-based permitting under the National Pollutant Discharge Elimination System (NPDES) permit program. Watershed-based NPDES permitting is an approach to developing NPDES permits for multiple point sources located within a defined geographic area (watershed boundaries) to meet water quality standards. This approach, aimed at achieving new efficiencies and environmental results, provides a process for considering all stressors within a hydrologically defined drainage basin or other geographic area, rather than addressing individual pollutant sources on a discharge-by-discharge basis. This guidance focuses on defining both the general approach and the process for watershed-based NPDES permitting. The guidance addresses issues related to program implementation, but it does not provide detailed technical information or address procedural and administrative actions related to permit issuance. Those will be covered in future guidance documents.