I live very close to the Bourne Bridge, which is one of 2 bridges that connects Cape Cod to the rest of MA.
Theres a little recreation area/parking lot under the Bourne Bridge (Capeside) that leads to the bike trail that runs along the canal. On my way home from work today, I noticed that they blocked off the access road with jersey barriers. The barriers are so close that you couldn't even really get a bike through- you'd have to lift it over.
I guess I'm gonna have to change my canal walking habit now, tho.