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The DigIndy Project is a 27-mile long network of 18 foot diameter deep rock tunnels being built 250-feet beneath the city. Beginning near the Indiana State Fairgrounds on the north, and ending on the south side of Indianapolis, DigIndy will be the largest public works project in the city's history.

Tunnel system will extend along Fall Creek, White River, Pogues Run, Pleasant Run and Bean Creek to create a collective, underground storage and transport facility for wastewater (sewage). All sewage stored and transported in the tunnel system is sewage that otherwise could have gone directly into our waterways. The tunnel system is a component of the federally-mandated plan to reduce raw sewage overflows into our waterways.

Adobe PDF Dig Indy Tunnel Facts

At more than 200-feet below ground, the tunnel system will store more than 200 million gallons of sewage during and after wet weather, and then slowly release the sewage to the Belmont Advanced Wastewater Treatment Plant when capacity becomes available. When the project is complete, sewage overflows into Indiana waterways will be significantly reduced, and water quality will be improved.

The tunnel system will be built in bedrock below the city using a piece of specialized equipment called a tunnel boring machine. After the machine bores the tunnel, a tunnel lining will be installed. The lining will help keep groundwater out and keep sewage in the tunnel. By using deep tunnel technology, disturbances to neighborhoods along the project route will be reduced.

The Deep Rock Tunnel Connector serves as the first phase of the Dig Indy Tunnel System. Improvements to the first phase resulted in modifications to later project phases and revealed the potential for significant cost savings. The Deep Rock Tunnel will extend about 8 miles from the Southport Sewage Treatment Plant in southern Marion County to the 1700 block of West Street in downtown Indianapolis.

The Fall Creek White River Tunnel will extend 7 to 10 miles, beginning near the Indiana State Fairgrounds on the north, running parallel to Fall Creek and White River, and ending near White River Parkway East Drive and West Street on the south side of Indianapolis. The exact route of the tunnel will be determined during design of the project and will continue to be refined to ensure long-term environmental and economic benefits.

Adobe PDF Deep Rock Tunnel Connector Facts

Adobe PDF Deep Rock Tunnel Connector FAQ

Adobe PDF Fall Creek White River Tunnel

The ProblemCombined sewers overflow into area rivers and streams causing a threat to public health
The SolutionA 27-mile long network of deep rock tunnels being built 250-feet beneath the city
The BenefitsEconomic and quality of life benefits as a result of the DigIndy project
RegulationConsent decree with the EPA and the Indiana Department of Environmental Management (IDEM)