Rock, also known as Hay Creek, is a local government-owned dam located in Clark County, Wisconsin. This arch-type dam was completed in 1938 and serves primarily for recreational purposes. With a height of 20 feet and a hydraulic height of 12 feet, Rock has a storage capacity of 1240 acre-feet and covers a surface area of 118 acres. The dam also has a controlled spillway and a maximum discharge capacity of 4260 cubic feet per second.

Despite being classified as having a low hazard potential and fair condition assessment, Rock is under state regulation and inspection by the Wisconsin Department of Natural Resources. The dam has a normal storage capacity of 526 acre-feet and is situated on Hay Creek, with a drainage area of 59 square miles. The risk assessment for Rock indicates a very high level of risk, emphasizing the importance of ongoing monitoring and maintenance to ensure the safety and functionality of this vital water resource in the region.