Skip to main content

Indianapolis Leverages ALL-TERRAIN SEWER for Septic Tank Replacement Initiative

case study Confluence PA replacing failing gravity sewerIndianapolis, Marion County, IN


In Indianapolis, the native soil is a dense, non-porous clay, with some established homes residing on tight lots on narrow roads. Whether these neighborhoods are in flood zones or above high water tables, there are thousands of septic tanks in close proximity.  When the ground becomes saturated, the septic tanks work in overtime and can fail or reach their lifespan prematurely, ultimately releasing raw sewage … into the neighborhoods’ backyards, ditches and streams, and the groundwater, jeopardizing public health.

In 2005, the city introduced its septic tank elimination program (STEP) to replace failing septic tanks with gravity sewer systems. However, this central sewer upgrade became extremely disruptive – with vast open trenches and large lift stations occupying the flat landscape – and came at a high cost to the homeowner and to the city.

Part 1 

Part 2


In 2016, Citizens Energy Group (a broad-based utility service company, providing natural gas, thermal energy, water, and wastewater services to about 900,000 people and thousands of businesses in the Indianapolis area) reorganized their septic tank replacement program into a cost-effective central sewer program, one of the largest and most comprehensive endeavors of this type in a major metro area to date. Designed for horizontal directional drilling (HDD), which enabled increased speed of corrective measures with its ease of installation, and utilizing E/One’s ALL-TERRAIN SEWER system, the project became more affordable, viable, and was the long-term solution for the city. With a savings of 46% in total cost for the construction, and a reduced construction cost of 60% for homeowners, choosing E/One’s grinder pump driven pressure sewer system over a gravity system expanded the program to areas that may have been out of reach, and connected more people in existing neighborhoods where there was not an affordable solution. Watch how this Design-Build project program was designed and delivered, learn how early engagement of homeowners was paramount, and find out what made E/One’s pressure sewer technology the system of choice for neighborhoods in Indianapolis- Marion County.

Septic Tank Elimination Program (STEP) Cost Comparison

CEG table

Download Cost Comparison Chart

Download File

Please complete all of the required fields and download will begin immediately. Note: you will only have to complete the form once.