Sanitary Sewer Overflows & Infiltration/Inflow

A sanitary sewer overflow (SSO) is an event in which untreated sewage is discharged from a sanitary sewer into the environment prior to reaching sewage treatment facilities, generally caused by too much rainwater or snow/ice melt. An SSO can spill raw sewage into home basements or out of manholes and into city streets, playgrounds, and waterways.

Infiltration and inflow (I/I) occurs when excess water flows into sewer pipes from groundwater and stormwater. Groundwater (infiltration) seeps into sewer pipes through holes, cracks, joint failures, and faulty connections. Excess water can enter sewer pipes through roof drains and broken or badly connected sewer service lines (inflow).

MetroConnects is working throughout Greenville County to reduce I&I and prevent SSOs through our proactive maintenance schedule and our extensive rehabilitation and replacement work. See Projects and Proactive v. Reactive  for more information.

To learn more about the hazards of aging infrastructure see What Can We Learn from Jackson? Mississippi’s Water Crisis is an Infrastructure Wake-up Call Part 1 and Part 2.

Improving Water Quality

The need to upgrade Greenville County’s deteriorating sewer collection system, which includes pipes that are more than 100 years old, was a major factor driving the regionalization of the county’s separate sewer collection systems. Bringing these disparate systems together into one allows MetroConnects to pool resources and implement a proactive maintenance plan to prioritize rehabilitation and replacement projects where they are needed most. Through proactive maintenance, rehabilitation and replacement, we are able to reduce SSOs and I&I, preventing contaminated wastewater from escaping into our fresh water systems and improving water quality overall.

Mitigating Health Risks

The CWF initiative will help reduce SSOs and I/I, improve water quality, mitigate health risks, keep costs down for ratepayers, and help ensure public safety. The Environmental Protection Agency (EPA) has found that SSOs caused by poor sewer collection system management poses substantial health and environmental challenges. Because SSOs contain raw sewage, they can carry bacteria, viruses, parasitic organisms, molds, fungi, and more. The diseases can range in severity from mild to life-threatening (see examples below). Exposure to pathogens can occur through sewage in drinking water sources, direct contact in areas of high public access, or waters used for recreation.

Ensuring Safety

By improving our wastewater collection systems and preventing SSOs, MetroConnects and the Clean Water Forward initiative are helping to create a cleaner, safer water system for all. Common pathogens, diseases and symptoms associated with SSOs include:

Common Pathogens & Diseases/Symptoms Associated with SSOs