Cohasset Tidal rip

 river rapid / white water, movie / film / TV location

Something of a cult favorite among Eastern New England paddlers, this is a play spot that will challenge you every time you visit. The Cohasset wave varies in character and difficulty by the minute due to rapidly changing water depth and tide height differential. In short...every day brings a new wave at Cohasset. It's also an excellent place for novices to practice since it's got eddies, a wave train, sharp squirt lines, and everything from flat water to a class II rapid.

The Cohasset wave forms on the incoming tide. About 3 hours before the actual high tide, the water moving out of the Gulf River (a tidal pool with a narrow channel to the harbor) goes slack. A short while later it begins to reverse direction and slowly starts flowing back into the tidal pool. The flow rate increases minute by minute and the current begins to pick up speed. Massive stone blocks from an old broken dam line the river bed near the mouth of the river. As the tide pushes back into the river the water is compressed and pushed backwards over the rocks and the wave begins to build. As the tide continues to press back into the harbor the water at the mouth of the river becomes congested, and the levels rise even faster. This accentuates the height differential between the harbor side of the broken dam and the river channel. Within 30 minutes of the slack water, the Gulf River has a 24 inch high standing wave and a wave train that reaches back 50 to 100 feet. At it's peak the wave can be 3 to 4 feet tall with a 12-18 inch trough in front of it. Depending upon the tide height differential and other less predictable conditions the wave will occasionally collapse and form a river wide hole. When this occurs the hole has a shallow angle of entry making it quite friendly.

The Boathouse was used as a filming location for "The Witches Of Eastwick" starring Jack Nicholson, Cher, Michelle Pfeiffer and Susan Sarandon.