If its in Ma, It would be the Conservation Commission. A plan would have had to be drawn and a public hearing with Abutters being notified for comments. DEP would have received a copy and would have issued a file number. Posted from my iPhone/Mobile device
In Mass there is a STATE permit under Chapter 91 that is required and as previously stated many locals are also involved. In Marshfield this would be a permit from the town and conservation commission. It is quite a process as engineered sitework elevation drawings are required.
Sorry to here that your honey hole isn't as easy to fish. There have been many many new docks going in...in both the North and South rivers over the last 5 years.
Hybrid Mode
