Calder (Zelph) is a state-owned dam located in Uintah, Utah, with a primary purpose of irrigation. Completed in 1989, this earth dam stands at a hydraulic height of 45 feet and a structural height of 50 feet, with a total length of 374 feet. It has a storage capacity of 2600 acre-feet, with a normal storage level of 1600 acre-feet, serving a drainage area of 35 square miles.

Managed by the Utah Division of Water Rights, Calder (Zelph) is subject to state regulation, permitting, inspection, and enforcement. With a significant hazard potential, the dam undergoes inspections every two years, the last one being in September 2019. While its condition is marked as "Not Rated," the dam remains a crucial structure in the region for water resource management.

Situated along Pot Creek and under the jurisdiction of the Omaha District, Calder (Zelph) plays a vital role in supporting agricultural activities in the area. With its strategic location and operational efficiency, the dam serves as a key component in the water infrastructure network of Utah, ensuring sustainable irrigation practices and water resource utilization for the community.