Summary
A growing body of research indicates that aging pipes and wastewater systems can boost your risk of becoming ill. Many municipalities along the East Coast and in the Midwest rely on a type of old, outdated wastewater management infrastructure.
In Atlanta, Georgia, large CSO events were associated with a nearly 10 percent increase in ER visits for GI illness. Children living within 500 meters of combined sewer overflow outlet sites in Cincinnati, Ohio were about 16 percent more likely to end up in the emergency department.
In the Massachusetts study, documented hospital visits for GI disease were highest in the summer. In the Atlanta research, higher income areas experienced a larger spike in GI illness after CSO events.
In exceptional cases, very large rainfall and CSO events can make the water incoming to treatment plants so turbid that it’s hard to effectively treat. Viruses and protozoan pathogens may be particularly difficult for standard water treatment strategies to manage.
In Canada, hundreds of thousands of cases of acute GI disease result from contaminated drinking water each year. A similar assessment of the U.S. published by the Centers for Disease Control and Prevention in 2023 estimated that more than 1.1 million cases of waterborne illness in a year were linked to drinking water.
The problem of CSOs and water contamination can’t be remedied at the individual level. CSO systems are no longer built, but cities that inherited them from decades or centuries past still live with the consequences.
The EPA already requires cities with combined sewer systems to have mitigation plans in place to reduce the impact of raw sewage flowing into waterways. Haley points out that many of these plans do not account for changing rainfall patterns or projected precipitation increases due to climate change.
