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The United States Lake Survey (USLS) was a hydrographic survey for the Great Lakes, New York Barge Canal, Lake Champlain and the Boundary Waters of the Canada–United States border between Minnesota and Ontario. The Survey's activities began on 31 March 1841, with the goal of surveying the Great Lakes. The Lake Survey was created within the United States Army Topographical Engineers (later the United States Army Corps of Engineers). Like the Commerce Department's United States Coast and Geodetic Survey, the Lake Survey had responsibility for the preparation and publication of nautical charts and other navigational aids. By 1882, the Survey had completed the original Congressional mandate, producing 76 charts, then disbanded. By 1901, the original survey and charting products required revision. The Lake Survey was reconstituted and its mission expanded. In addition to traditional survey, charting, and navigation information responsibilities, the Lake Survey was also responsible for studies on lake levels and associated river flow.
