Two construction projects are underway in Bridgewater.  One is a new entryway at the Senior Center, partly underwritten by the Town but mostly by private donations to the Senior Center Building Fund.  The other project is a new Pavilion concrete floor and fireplace at the Recreation Area. Bridgewater officials say the supporting posts also require a new anchoring system to improve long term structural integrity.  Both jobs are expected to be finished by June 1st.