The tides of the Bay of Fundy and its headwaters are among the highest in the world. Twice each day the waters of this funnel-shaped basin rise and fall. The variation in water level is greatest in the narrow headwaters where the normal range is from 30 to 40 feet, but at high tide it may be from 50 to 60 feet between high and low water. Along the protected parts of the shoreline, and in the river estuaries, extensive deposits of silt were laid down similar to deltas and flood plains. These wide alluvial lowlands, protected by dykes, now form some of the best farm lands of the region.
Tides occur on all coasts in the Maritimes but those of the Gulf of St. Lawrence and the Atlantic coasts do not have a range of more than ten feet.
Compared with those in other provinces, the rivers of the Maritime region are rather small. The heavy rainfall and wooded character of their drainage areas give them a more reliable flow, however, and many of them are harnessed for the development of hydro-electric energy.
The St. John River, rising in the state of Maine, has a length of 400 miles and a drainage basin of over 20,000 square miles in Maine, Quebec and New Brunswick. Draining a forested country, this river and its tributaries have long been used for the transportation of timber. The lower course of the river, between St. John and Frederic ton is navigable for small steamers. A large power generating station is located at Grand Falls.
Other rivers in New Brunswick include the Restigouche, Nipisiguit, Miramichi, Petitcodiac and St. Croix.
In Nova Scotia there are many short rivers, including the Annapolis, Tusket, Liverpool, Lahave, Musquodoboit, Sheet Harbour, St. Mary, Pictou and Shubenacadie.