MS4 fact sheet - Septic System Maintenance Programs
Septic System Maintenance Programs
Development of an effective management program for decentralized wastewater treatment systems
Septic systems, also known as onsite/decentralized wastewater treatment systems and subsurface sewage treatment systems (SSTS), treat sewage from homes and businesses that are not connected to a centralized wastewater treatment plant. Septic systems can vary in size and the number of dwellings served and include individual and cluster SSTS. Septic systems can be of conventional design (heavily relying on the soil for treatment along with dispersal) or use pre-soil treatment technologies like constructed wetlands, media filters, or aerobic treatment tanks followed by dispersal (with limited final treatment) in the soil. Soil treatment and dispersal options include in-ground trenches or beds or above ground at-grade or mound systems. The type of soil dispersal system is chosen based on the treatment abilities of the native soil in combination with the effectiveness of any pre-soil treatment that may be employed. SSTS can be protective of public health and water quality if properly planned, sited, designed, constructed, installed, operated, and maintained.
This fact sheet summarizes a step-by-step approach to developing a community management program for SSTS. It also provides an overview of the five management models outlined in EPA’s Voluntary National Guidelines for Management of Onsite and Clustered (Decentralized) Wastewater Treatment Systems. While this factsheet, based on EPA guidance, provides direction to MS4’s, Minnesota Statutes 115.55 and 115.56, which regulate SSTS, must also be consulted in the development of a comprehensive management program.
Benefits / Pollution Reduction
Although some management programs are effective, many existing rules that regulate septic systems are not adequate to ensure proper operation and maintenance. Failure of septic systems is a term subject to much debate. Based on local units of government estimates, approximately 10 percent of all systems back up into homes or have wastewater emerging on the ground surface, and approximately 25% of the systems in Minnesota fail to protect groundwater.