Grasmere East Dam, also known as Grasmere South Reservoir East Dam, is a privately owned structure located in Owyhee, Idaho. This earth dam, primarily used for irrigation purposes, stands at a height of 10.9 feet with a hydraulic height of 7.4 feet. The dam has a storage capacity of 452.6 acre-feet and covers a surface area of 152.9 acres, serving the surrounding area's water needs from the Rattlesnake Creek and Marys Creek.

Despite its essential role in irrigation, the Grasmere East Dam is facing significant concerns regarding its condition and hazard potential. The dam's poor condition assessment highlights the urgent need for maintenance and improvement to mitigate risks. With a moderate risk rating and a significant hazard potential, it is crucial for regulatory agencies like the Idaho Department of Water Resources to ensure proper inspection, enforcement, and management measures to safeguard the surrounding communities and water resources. Climate enthusiasts and water resource advocates should closely monitor the dam's maintenance and regulatory actions to address these pressing issues.