The reservoir was created by a dam on the Mohawk River, for which construction began in 1908. The dam is on the south side of the reservoir, southwest of Delta Lake State Park. Originally, the purpose of the reservoir was to guarantee sufficient water for the Erie Canal; today, however, it is used to control flooding in the Mohawk basin. The reservoir contains 2.7 million cubic feet (76,000 m3) of water.
The dam flooded the community of Delta, which was located on the west bank of the river. Most of the structures of the village were torn down and moved to new locations before the inundation.