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What is DigIndy?

The DigIndy Tunnel System is a 28-mile long network of 18-foot diameter deep rock tunnels being built 250-feet beneath the city. Along with other projects in the combined sewer system and at Citizens two advanced wastewater treatment plants, the $2 billion program is Indy’s solution to reducing combined sewer overflows into area waterways by up to 97 percent, and keeping the utility in compliance with a Consent Decree with the U.S. Environmental Protection Agency.

The Problem

Combined sewers convey both storm water and wastewater (sewage) in one piping system. Historically, more than 800 communities across the United States built combined sewers once indoor plumbing became commonplace in the late 1800s.

During normal rain events with ¼-inch of rainfall or more, the combined system capacity can become overwhelmed, resulting in a mixture of storm water and wastewater overflowing into area waterways. This is referred to as a combined sewer overflow (CSO) event, which causes a threat to public health and the environment.

The Benefits

Our water and wastewater investments will have enormous benefits on the quality of life and the local economy. Cleaner rivers and streams will lead to enhanced recreational opportunities and community revitalization across Central Indiana. At the same time, Citizens system investments will create thousands of good paying jobs.