The Sandy Lake Dam is located on the Sandy River, 1 ¼ miles above the junction of the Sandy and Mississippi rivers.
The original timber dam dates from 1892-1895. In 1896, a navigation lock, the only one in the Headwaters reservoir system, was completed. The original timber structure showed deterioration by 1904 and reconstruction began in 1908. Steamboats and horse-drawn wagons transported the concrete plant used at the Pine River Dam to this site. The lock was also reconstructed and the operating machinery installed in 1912. The metal-sided shelter house was built over the machinery building in 1914. The 30-foot wide lock is no longer in use. In 1957, it was converted to a spillway containing five sluice bays.
Eight buildings were constructed at the beginning of work on the dam in 1892. In addition to the watchman’s quarters there were a dining room and kitchen, a warehouse, carpenter and blacksmith shops, a tool house, a stable, and laborer quarters. Conversion of the watchman’s quarters into a dam tender’s house began about 1910. The house was removed in 1991.
The dam site was near the terminus of the Savanna Portage, which connected Sandy Lake and the Upper Mississippi River with the St. Louis River and Lake Superior. Explorers, fur traders and missionaries used the portage between 1755 and 1855. In 1794, to the south of the dam site at Brown’s Point on Big Sandy Lake, the Northwest Company established a fur trading post. In 1830, the American Fur Company established a post at Sandy Lake at the junction of the Mississippi and Sandy rivers, just to the west of the present dam. William Aitkin, the operator and several missionaries resided here between about 1832 and 1855. A steamboat landing at this site operated after about 1870, bringing supplies and settlers to the area.
Fredrick Ayer established a mission and school near the dam site in 1832-33. A later school building stood northwest of the dam. It was moved off the damsite in the 1950s but a rubble foundation remains. A cemetery containing the graves of Native Americans and early settlers is found on the small hill near the site of the dam tender’s house.
Mississippi River Headwaters History brochure