Boston Mayor Thomas M. Menino will join Whittier Street Health Center officials today as they break ground on a new $35 million facility in Roxbury.

The new 78,900-square-foot facility, to be located at 1290 Tremont St. across the street from their existing facility, includes the construction of a single six-story building on a sub-divided parcel of land within Parcel P3 on Tremont Street.

The facility will house a variety of medical and dental offices, a pharmacy, a physical therapy clinic, and community space. It will also include 5,000 square feet of space which will house a mammography clinic and cancer screening and exam rooms in collaboration with Dana-Farber Cancer Institute.