Citizens Energy Group gives limestone quarry near Geist Reservoir new purpose

HAMILTON COUNTY — For decades, the site on the edge of Geist Reservoir off of Oilo Road was an active limestone quarry.

But Citizens Energy Group has given this crater a new use.

A more than 200 foot limestone wall that separates Geist Reservoir from the new Citizens Reservoir,

Geist Reservoir is 1,800 acres, holds over 6 billion gallons of water and has an average depth around 10 feet. Citizens Reservoir is 90 acres, holds a little more than 3 billion gallons and is 230 feet deep.

When drought causes water levels to drop on Geist, this new water source will help bring water levels back up.

"We can get 30 million gallons a day pumping out of this reservoir going back into Geist Reservoir," Ryan Taylor, purification plant engineering manager, said. "Then during the wet season, we can get 100 million gallons to come back into the quarry to fill it up."

"It enables us to balance the withdrawals from our three primary sources of water: Geist Reservoir, Morse Reservoir and the White River," Dan Considine, a spokesperson for Citizens Energy Group, said.

The reservoir increases the available water supply to eight counties in central Indiana, including Marion County and Indianapolis.

The change from quarry to holding tank began in 2019. This new reservoir was filled in 2021 with excess water from Geist.

"It's very unique in Indiana. It's a very unique opportunity because our quarry is right next to our reservoir. We only needed a few hundred feet to connect the two," Taylor said.

This new water resource will help handle future population and economic growth.

"We think this reservoir will provide the additional water supply we need over the next 20 years," Considine said.