ANNAPOLIS, Md. (AP) — Back-to-back late-summer storms dumped an estimated 4 million tons of Susquehanna River sediment into the Chesapeake Bay, threatening grasses, oysters and other ecologically important species.

Now, state and federal officials say they plan to study sediments still behind Susquehanna dams and strategies for controlling them.

The three-year study announced Tuesday will be conducted by the Army Corps of Engineers, Maryland state agencies, the Susquehanna River Basin Commission and the Nature Conservancy. They say only the Conowingo Dam closest to the bay has remaining storage capacity, and is expected to reach capacity in 15 to 20 years.

The Chesapeake Bay Program, which leads bay restoration efforts, says the storm scoured between 2.5 million and 7 million tons of sediment from the lower Susquehanna reservoir system.

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