The first dam in South Natick, located on the Charles River upstream from the Pleasant Street bridge, dates back to 1760. Before this timber structure was built, Indians had constructed in the vicinity a fishweir - an ancient structure resembling a fence designed to catch fish.
More than a century earlier, Rev. John Eliot established the first and most successful Praying Indian town on the banks of the Charles River. The 17th-century term "Praying Indians" refers to Native Americans who converted to Christianity, and who lived and fished at the site long before Eliot's arrival.
Later, a mill was built near the site that has long since disappeared. Only mill stones remain to mark the spot.
The current dam was built in 1934, representing the fourth structure at the site.
Today, the dam represents the centerpiece of municipal green space on the river complete with a park that can be accessed off Mill Lane.
The dam itself is an earth embankment that stretches approximately 300 feet with a concrete spillway, visible from Mill Lane, that measures approximately 80 feet long and 8 feet high. The dam has a 500-acre-foot capacity with a normal storage of 220 acre feet, and drains an area of 165 square miles.