Diving & Snorkeling.
The North Channel between Cornwall and Cornwall Island carries unusually clear freshwater because the Moses-Saunders Power Dam upstream releases well-flushed water from Lake St. Lawrence.
Cornwall Tourism documents the area as a regional freshwater scuba destination, with sheltered conditions on the channel between the Cornwall waterfront and the Akwesasne shore.
The brief.
The river runs cold and clear year-round on the channel below the dam; visibility is typical of dam-controlled tailwater conditions and the channel itself sits sheltered from prevailing west wind by the bulk of Cornwall Island. The dive water is on the international shipping route — the Seaway main channel passes south of Cornwall Island — so divers must observe Seaway navigation rules and stay clear of commercial-shipping lanes.
June through September is the warmest visibility window; year-round dives are possible.
1. places.
- 01
St. Lawrence River — North Channel
Between Cornwall and Cornwall Island (Akwesasne side); well-flushed clear freshwater downstream of the Moses-Saunders dam.
Map ↗
Today's read.
Outside the typical season window.
By the book.
- 01The St. Lawrence Seaway international shipping channel passes south of Cornwall Island; divers must stay clear of the commercial shipping lane and observe Seaway navigation rules.Source ↗
- 02Cornwall Island is the Mohawk Territory of Akwesasne; access on or around the Akwesasne shore is governed by the Mohawk Council of Akwesasne.Source ↗
