Boylston Properties and The Wilder Cos. Plans have received unanimous approval from The Watertown Planning Board to redevelop and expand the former Arsenal Mall in Watertown, MA.

The venture disclosed plans in early December to develop Arsenal Yards, a one million-square-foot mixed-use project that at full build-out will consist of 350,000 square feet of retail space, 500 residential units and 100,000 square feet of office space.

The project…