During the early years of this century, on-site wastewater management was basically a trial-and-error process. Systems that failed were not of concern because on-site wastewater disposal was usually only used in rural areas with sparse population. There was little need for detailed knowledge; therefore, on-site wastewater treatment and disposal got little attention.

As rural electrification enabled more people to install indoor plumbing and as rural and suburban populations grew, a greater need arose for concise information about proper installation and operation of on-site systems. Almost 70 years have passed since Henry Ryon first suggested that the performance of an on-site system depended on the percolation rate of the soil. Since that time, many studies have been conducted on on-site system requirements and performance.

This section presents the important principles and guidelines learned about on-site wastewater treatment and disposal.

From the North Carolina Onsite Guidance Manual