The On-site Water Protection Section (OSWPS) is responsible for providing a comprehensive program for control of sub-surface on-site wastewater treatment and disposal as a joint effort among the local health departments and the On-site Water Protection Section. To carry out this mission, the OSWPS provides statewide regulatory and consultative services related to the collection, treatment and disposal of wastewater to local health departments and numerous other clients, including builders, developers, land owners, system installers, system operators, engineers, soil scientists, geologists, environmental health consultants and others.

The OSWPS, which is part of the N.C. Department of Environment and Natural Resources, also develops and implements new, revised or amended statewide regulations. The OSWPS does not deal with surface applications of treated wastewater or treated wastewater that is discharged directly into surface waters.