NORMAN, Oklahoma - The city of Norman says it's thinking ahead to the future with its proposed plan to increase the city's water supply. But it involves taking highly treated waste water and dumping it into Lake Thunderbird.

Lake Thunderbird is the primary water source to not only Norman, but also Midwest City and Del City. Two cities that are leery the filtered waste water won't take all the harmful contaminants.

On these hot summer days, water becomes a necessity to survive. But now a proposed plan to increase the supply has some cities questioning how clean that next glass of water will be.

The City of Norman is considering dumping highly filtered waste water into Lake Thunderbird; waste water that once was flushed from a toilet or went down the drain.

“It'd be very, very highly treated water put in Lake Thunderbird. It'd mix there and resonate for several months and then it would return to the water treatment plant where it'd be treated again,” said Ken Komiske, the Director of Norman's Utility Department.

The city of Norman believes dumping this highly purified waste water into Lake Thunderbird it'll actually improve the water quality.

Still, Midwest City and Del City are skeptical about this plan and both oppose it.

Del City's Police department posted its concerns on Facebook and called it a "brewing situation" and said "there is no way to completely clean the pharmaceuticals from the water."

A reluctance Midwest City echoed at a city council meeting recently.

“We would like those other city's approvals absolutely because we all share the reservoir. We all end up drinking it,” Komiske.

Komiske explained more research needs to be done, specifically the best way to treat Norman's waste water before pumping into the lake.

Even after studies are complete and voters approve of the spending, Komiske says it'll at least be five years before the lake sees any of the filtered waste water.

“This would be a drought prevention or drought proof source of water for all three cities,” said Komiske.

Norman says it's not the only city in the state that is looking into this as a way to increase the water supply. Currently the Department of Environmental Quality (DEQ) is working to develop statewide rules on dumping highly filtered waste water into water supplies.