Opponents of a Somerset County wind energy facility pushed forward with a House proposal to slow the project Saturday, a victory for Southern Maryland over the Eastern Shore in a rare contest of rural regions.

On a 40-80 vote, the House defeated an amendment that would have weakened a bill to impose a 15-month delay on the construction of high turbines for the Eastern Shore project.

Lawmakers from Southern Maryland -- across the Chesapeake Bay -- are concerned about how the wind facility would affect Patuxent Naval Air Station,  one of the state’s largest military bases and the economic engine of that region.

Some fear that turbines as high as 600 feet could disrupt radar operations at Pax River in Southern Maryland. Delegates from the area want to delay the construction of turbines higher than 340 feet until the completion of a study due in July 2015.

“Pax River is a $7.5 billion industry we should be sticking up to protect,” said Del. John L. Bohanan Jr., a St. Mary’s County Democrat.

Eastern Shore lawmakers contended that there was no good reason for the legislature to delay a lucrative project in one of Maryland’s poorest counties when the Navy has to sign off on any deal before construction can begin.

Their amendment would have allowed construction to proceed once the Navy and other agencies signed off on it.

The amendment vote cut across party lines, as liberal supporters of wind energy joined forces with conservative Eastern Shore lawmakers in trying to scuttle the bill, which will move on to a final House vote Monday.