Rye Grass Swale, also known as Graves Reservoir, is a private water resource located in Modoc, California. This earth dam was completed in 1923 and stands at a height of 20 feet with a storage capacity of 530 acre-feet. It serves the primary purpose of water supply for irrigation and other uses in the surrounding area, with a satisfactory condition assessment and low hazard potential.

Managed by the California Department of Water Resources and regulated by the Safety of Dams agency, Rye Grass Swale plays a crucial role in ensuring the water security of the region. With a drainage area of 14 square miles and a surface area of 120 acres, this reservoir on Tr Canyon Creek in Calpine provides essential water storage for the community. Its last inspection in June 2020 indicated a satisfactory condition, highlighting its importance in the local water infrastructure.

With its strategic location and historical significance, Rye Grass Swale continues to be a vital resource for water management in California. Its low hazard potential and satisfactory condition make it a reliable asset for water supply, irrigation, and other purposes. As climate change impacts water resources, structures like Rye Grass Swale play a crucial role in ensuring sustainable water management practices for the future.