Buying a lot in Chatham County, NC: septic, sewer, zoning and flood checks

By Nara Bakthisaran. Sources checked Oct 16, 2026. Always confirm with the county before you pay or close.

Septic and soil evaluation process

In NC, the old "perc test" is now a soil and site evaluation by county Environmental Health. If the site qualifies, the county issues an Improvement Permit (IP): where the system can go, what type, and for how many bedrooms. The Construction Authorization (CA/ATC) comes next and is needed before a building permit. An IP for a 3-bedroom house may not cover 4 bedrooms. Improvement Permits are generally valid for 5 years.

This is a two-step process: the Improvement Permit (site evaluation), then the Construction Authorization. Environmental Health is at 919-542-8208, and it doesn't take payments after 4:00 p.m. Advanced systems (Type IIIb and up) carry ongoing monitoring fees, so factor those into what a lot will cost to own. The county doesn't publish turnaround times; ask Environmental Health when you apply.

Environmental Health contact page: https://www.chathamcountync.gov/government/departments-programs-a-h/environmental-health/wastewater-and-septic-permits-monitoring

Fees as published

Official fee schedule, effective July 1, 2024: https://www.chathamcountync.gov/home/showpublisheddocument/64863/638591534624500000

Sewer and city utilities

Pittsboro water and sewer is now run by TriRiver Water (the county's utilities page redirects there: https://www.chathamcountync.gov/government/departments-programs-i-z/utilities-water?locale=en; customer service 919-775-8215). Siler City runs its own water and sewer, so ask the town. Most rural Chatham lots need a well and septic. If sewer is available, you generally skip septic permitting, but there may be tap or extension costs.

Zoning and setbacks: where to check

Chatham County Planning, 80-A East Street, Pittsboro; 919-542-8204 (https://www.chathamcountync.gov/government/departments-programs-i-z/planning). Residential zoning compliance and floodplain determinations go through the county's online permit portal. The new UDO (adopted Nov. 2024) isn't in effect yet; current rules still apply. Inside Pittsboro or Siler City: that town's planning office. Ask about the zoning district, minimum lot size, front, side and rear setbacks, road frontage and access, and any HOA or recorded restrictions.

Flood check

• FEMA Flood Map Service Center: https://msc.fema.gov/portal/search. Look up the address and check for zones A or AE.
• First Street (riskfactor.com): free property-level flood risk score that models future risk beyond FEMA zones. It's useful context but not a regulatory determination.

Pre-purchase checklist

• Make the contract contingent on an IP (or a soil scientist's report) for your bedroom count, and give it enough time
• Is a permit already on file? Get a copy and check its date (5-year validity)
• Is sewer available, and what does connection cost?
• Will a well be needed? Ask neighbors about water quantity and quality
• Zoning, setbacks and minimum lot size; deed restrictions and HOA
• Legal road access (not landlocked) and driveway permit (NCDOT if it's a state road)
• FEMA flood zone, wetlands, streams and buffers
• Survey with corners marked (also needed for the soil evaluation visit)
• Title search and easements
• Rough site-work budget: clearing, grading, a longer driveway, an alternative septic system

General guidance: NC State Extension, https://content.ces.ncsu.edu/investigate-before-you-invest · NC Real Estate Commission, https://www.ncrec.gov/Brochures/DueDiligenceBrochure.pdf