Rock Gap, also known as Hartman Gulch, is a privately owned dam located in Grand County, Colorado. Built in 1966, this earth dam stands at 30 feet high and serves primarily for recreation purposes, with irrigation being a secondary function. The dam has a storage capacity of 84 acre-feet and a surface area of 7 acres, providing a tranquil spot for water enthusiasts to enjoy.

Managed by the Colorado Department of Water Resources, Rock Gap is regulated, inspected, and enforced by state authorities to ensure its safety and compliance with regulations. The dam's hazard potential is rated as low, with a fair condition assessment as of October 2019. With a moderate risk level and a controlled spillway type, Rock Gap remains a popular destination for outdoor activities like fishing, boating, and picnicking in the scenic surroundings of Hartman Gulch.

Although Rock Gap has not undergone significant modifications over the years, it continues to be a well-maintained structure with a regular inspection frequency of 6 years. Located in the picturesque city of State Bridge, this dam offers a peaceful retreat for water resource and climate enthusiasts to appreciate the beauty of Colorado's natural landscapes while engaging in recreational activities along the tranquil waters of Hartman Gulch.