SAINT CLAIR, LAKE

lake in west-central Tasmania, Australia, lying at the southern boundary of Cradle MountainLake St. Clair National Park at the terminus of a 53-mile [85-kilometre] walking track from the mountain. It has an area of 11 square miles (28 square km), measures 9 miles by 1 mile (14.5 by 1.6 km), and lies at an elevation of 2,417 feet (737 m) on Tasmania's Central Plateau. It fills a valley once deepened by a glacier and then dammed with a moraine (glacial debris). The maximum depth approaches 700 feet (215 m) on the west, making St. Clair Australia's deepest lake. It is the source of the Derwent River's west arm, and its water is used by the Tarraleah hydroelectric-power station. Probably explored by W.S. Sharland, a surveyor, in 1832, it was named in 1835 by the surveyor general George Frankland to honour the St. Clair family of Scotland's Loch Lomond. The lake is accessible via the Lyell Highway, through Derwent Bridge, from Hobart, 108 miles (174 km) southeast. expansive shallow basin, forming part of the boundary between Michigan, U.S., and Ontario, Can. Roughly circular, with a surface area of 467 square miles (1,210 square km), it connects with the St. Clair River and Lake Huron (north) and with the Detroit River and Lake Erie (south). It is 26 miles (42 km) long (north to south), and 24 miles (39 km) wide (east to west) and has a mean surface altitude of 573 feet (175 m). The lake's drainage basin covers an area of 7,420 square miles (19,220 square km). Its northeastern shoreline is marked by the large delta of the St. Clair River, with seven channels. St. Lawrence Seaway shipping is afforded a minimum channel depth of 27 feet (8 m), and the lake region forms a popular summer recreation area. Suburbs of Detroit lie on the western shore, but there are no important ports on the lake. The French explorer Louis Jolliet was believed to be the first European to visit the lake area (1669); but some credit the discovery to two French missionaries (1670). The lake and the St. Clair River were named by the French explorers Robert Cavelier, sieur de La Salle, and Father Louis Hennepin, who arrived on St. Clair's Day in 1679.