Grassy Lake, located in Teton County, Wyoming, is a Federal-owned reservoir with a primary purpose of irrigation. Built in 1938, this Earth-type dam stands at a height of 118 feet and has a storage capacity of 16,210 acre-feet. The dam spans 1,170 feet and is regulated by the Bureau of Reclamation, ensuring proper inspection, permitting, and enforcement measures are in place to maintain its structural integrity.

With a hazard potential classified as high, Grassy Lake is under regular inspection and monitoring to assess its condition and potential risks. While the dam has undergone modifications in 2005 for hydraulic and structural improvements, its spillway type remains uncontrolled. The reservoir's drainage area of 12 square miles feeds into the Grassy Creek, with a maximum discharge capacity of 675 cubic feet per second.

As a vital water resource for irrigation in the region, Grassy Lake serves as a testament to the careful management and regulation of water infrastructure by the Bureau of Reclamation. Its historical significance, combined with its ongoing risk assessment and management efforts, make it a focal point for water resource and climate enthusiasts seeking to understand the intersection of infrastructure development and environmental stewardship in the American West.