Jim Thompson

New reef created in Chesapeake Bay

New reef created in Chesapeake Bay

Concrete that once blocked fish from swimming up the Patapsco River to spawn has a new life as home for aquatic creatures at the bottom of the Chesapeake Bay.

Water cannons blasted chunks of the demolished Simkins Dam off a barge Wednesday, completing the structure's transition from a river barrier to an oyster reef the size of two football fields. On Thursday and Monday, the Chesapeake Bay Foundation will seed the site at the mouth of the Chester River with 4 million baby oysters.

"This is definitely unique in dam removal projects," said Serena McClain, restoration director of the nonprofit group American Rivers.

The concrete chunks, most the size of soccer...