Non-Point Source Pollution Program: Resources
Watersheds Maps and Statistics
Census figures for 2000 and 2010 did not include the number of households using septic systems. However, as of 1990, nearly 50% of North Carolinians used septic tank systems.
North Carolina Watersheds Map
This map illustrates the boundaries of the 17 watersheds in NC.

County Stats and Watershed Maps
Check the density of onsite systems or system statistics by county as of 1990, and download individual river basin maps.
- Broad River Basin:
- Catawba River Basin:
- Cape Fear River Basin:
- Chowan River Basin:
- French Broad River Basin
- Hiwassee River Basin
- Little Tennessee River Basin
- Lumber River Basin:
- Neuse River Basin:
- New River Basin:
- Pasquotank River Basin:
- Roanoke River Basin:
- Savannah River Basin:
- Tar-Pamlico River Basin:
- Watauga River Basin:
- White Oak River Basin:
- Yadkin/Pee Dee River Basin:
BMPs Checklists, Planning Tools, Training Materials and Presentations
- Literature Review: Constituents, Indicators and Construction Characteristics
- Pathogen Reduction: Fixed Biofilm Wastewater Treatment (PDF)
- Agent Training: Basics of Onsite Wastewater for Public Outreach
- Annotated Bibliography: Softeners and Septic Systems
- Answering Homeowner Questions About Septic Systems
- Decentralized Wastewater Cost Estimation Factsheets
- Decentralized Wastewater Treatment Glossary
- History of Onsite Wastewater in N.C. (PDF)
- Installation BMPs Checklists
- NC Low Impact Development Guidebook
- O&M BMPs Checklists
- Point of Sale Inspection (NC) BMPs Checklists
- Troubleshooting BMPs Checklists
North Carolina Academic, Agency and Organizational Links
National and International Academic, Agency and Organizational Links
- Consortium of Institutes for Decentralized Wastewater Treatment (CIDWT)
- Federal Funding Sources for Small Community Wastewater Systems (EPA)
- Homeowner Guide to Septic Systems, Spanish version (EPA)
- National Environmental Services Center (NESC)
- Non-point Source News-Notes (EPA)
- Septic (Onsite/Decentralized) Systems (EPA)
- Virginia Department of Health
- Water Environment and Reuse Foundation (WERF)