State officials say at least nine Iowa cities could be sanctioned by the E.P.A. because they’ve yet to make an upgrade to their aging sewer systems. The feds are demanding that communities separate their storm water, the rain that flows into street drains during a thunderstorm, from their waste water, the stuff that’s flushed down the toilet.

The main reason for the move is to reduce the number of cities which see their water treatment systems overflow and discharge into nearby streams when there are heavy rains. Barb Lynch of the Iowa Department of Natural Resources say there are other health concerns.

“In many cases where the sewers get overloaded because there’s too much water coming in they actually back up into citizen’s basements and that certainly is a health hazard,” she says. “And then if you have untreated sewage flowing out of the manhole or down out of the pipe down to the creek directly, you have other health issues that you have to be concerned about with pathogens.”

According to Lynch there are nine Iowa cities that have yet to separate their water treatment systems — Des Moines, Clinton, Muscatine, Keokuk, Burlington, Wapello, Fort Madison, Ottumwa and Spencer. The E.P.A. is asking that those cities make the water treatment system upgrade within the next 15 to 17 years, but Lynch says some of the communities are asking for more time because of the cost.

“The infrastructure is aging so badly throughout the state that it takes more and more money to fix it,” she says. In Des Moines, for example, the price tag for such an upgrade is $250 million. For Ottumwa, it’s $220 million. Lynch says there are some grants and low interest loans available, but residents likely will see higher sewer and water bills as the price is passed along to the people who use the system daily.

“It’s going to take local money. It’s going to take user fees. It’s going to take state and federal money as well,” Lynch says. The communities are asking federal officials for permission to spread the cost of the upgrades out over 20 to 25 years rather than just 15 so residents won’t see such huge increases in their sewer and water bills.