Located in Uinta, Wyoming, the Lachapelle Enlargement of Ben Reservoir is a private irrigation dam designed by M. Malner and completed in 1997. This earth dam stands at a height of 34 feet with a hydraulic height of 29 feet and a length of 1020 feet. It serves the primary purpose of irrigation and has a storage capacity of 303 acre-feet, providing water for agricultural use in the region.

The dam is situated on the East Branch of Lachapelle Creek and is regulated by the State of Wyoming with inspection, permitting, and enforcement processes in place. Despite its poor condition assessment in 2018, the hazard potential is considered low with a moderate risk level assigned. The spillway is uncontrolled with a width of 20 feet, and the outlet gates consist of a valve system.

With Liz Cheney (R) representing Congressional District 00, Wyoming, the Lachapelle Enlargement of Ben Reservoir plays a vital role in water resource management in the area. Its strategic location in Evanston and contribution to irrigation make it a crucial infrastructure for sustaining agricultural activities in the region. Despite its condition, the dam continues to serve as a key component of the local water supply system.