On Monday night, the town of Watertown Planning Board unanimously approved the final site plan for a 124,000-square-foot expansion at Salmon Run Mall.

The unanimous decision will push forward a project that has hung in environmental review limbo for the last three years.

The only condition of the approval was that plans be submitted to the town to show a proposed sewer easement on the property.

According to plans, the new spaces will include 20,000-square-feet between the former Montgomery Ward building and Dick's Sporting Goods and 104,000-square-feet space near Gander Mountain.

The mall currently has 646,000 square feet of gross leasable area.

In March, Planning Board members accepted a final environmental impact statement, part of a review process mandated by the state's Environmental Quality Review Act.

The mall's draft environmental impact statement had been submitted in 2006.

Mall manager Mary P. Dudo was unavailable for comment Tuesday. She has previously said that ground could be broken this summer for the expansion.