Franklin Surveys Provided Construction Support in the Caswell Cove Revetment Rehabilitation on the Housatonic River in Milford, Connecticut
The Caswell Cove Condominiums are located on the shore of the Housatonic River in Milford, Connecticut. The river’s name comes from the Mohican phrase “usi-a-di-en-uk”, meaning “beyond the mountain place” or “river of the mountain place”.
The existing revetment wall protecting the shoreline of this condo community was crumbling. We were hired by the wall contractor to lay out stationing along approximately a quarter mile of seawall, including GNSS control establishment, leveling, and placement of grade stakes and offsets on project stationing. The surveyor of record on the project was apparently unreachable, but we are more than comfortable establishing our own control point network.
We performed a resection survey and multiple GNSS (global navigation satellite system, commonly GPS) observations to establish the project vertical datum. As a coastline project, it is critical that the project be built at the designed elevations. In this case, the project vertical datum was the North American Vertical Datum of 1988 (NAVD 88). This is the datum that is now used by the Federal Emergency Management Agency (FEMA) for flood mapping.
Here is a video by Ocean County Construction demonstrating the scope of the shoreline revetment and seawall rebuild.