Willard Reservoir is located in the southwestern corner of Huron County on OH-61, two miles north of New Haven, in New Haven Township.

Willard Reservoir is an upground reservoir; water is obtained by pumping from the Huron River, which runs along the east side of the reservoir. It was completed and filled in 1971 and designed to provide water for the city of Willard, low-flow stream augmentation to the Huron River, and water for agricultural use and recreation.

Willard Reservoir has a surface area of 199 acres at maximum water level and a storage capacity of approximately 1.9 billion gallons. Its maximum depth of 46 feet is located near the eastern shoreline, with an average depth of 26 feet. The reservoir bottom is uniformly deep, so there is limited shallow water. No fisheries enhancement facilities were incorporated into this reservoir.