LANSING (WWJ/AP) – State officials say billions of gallons of raw and partially treated sewage was dumped in Detroit area rivers and streams after flooding from heavy rains earlier this month.

Department of Environmental Quality spokeswoman Laura Verona told The Detroit News that about 46 percent of the nearly 10 billion gallons of sewage released Aug. 11 by water treatment facilities was raw, diluted or partially treated sewage.

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The 4.5 billion gallons of sewage would be the equivalent of submerging Detroit’s Belle Isle in about 14 feet of water, the newspaper said.

The sewage overflows impact local rivers and streams as well as Lake Erie and Lake St. Clair. The overflows mean beaches could stay closed for longer if E.coli is detected in the water. They could also cause an algae bloom.

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Combined sewers and retention basins in some communities in Wayne, Oakland and Macomb counties overflowed during the storm that also left five major freeways under several feet of water, forcing thousands of people to abandon their water-logged cars.  Some areas received more than 6 inches of rain.

Tens of thousands of homes across the metro area were flooded, some with several feet of water — and sewage — in their basements.

The state agency has put together a preliminary report on the sewage release, although it’s unclear when a final report will be ready.

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