PORTLAND – The Department of Defense has determined that the Brunswick Naval Air Station’s Topsham Annex is surplus property, giving a boost to efforts to redevelop the 74-acre site for another use.

Sens. Susan Collins and Olympia Snowe made the announcement, calling it a critical step in the successful redevelopment of the land and facilities at the Topsham Annex.

Adjacent to downtown Topsham, the annex is a general support facility for the Brunswick Naval Air Station, providing a site for housing units, a commissary, a training facility, office space and a fire station.

“We look forward to continuing to work with the Department of Defense and the Topsham Local Redevelopment Authority as they create a community-driven, comprehensive reuse plan,” Collins and Snowe said in a joint statement.

The Brunswick Naval Air Station, a longtime base for submarine-chasing patrol planes, is slated to close by 2011.