Cummings Reservoir No. 1, also known as Lower Cummings, is a private water supply reservoir located in Canby, California. Built in 1912, this earth dam stands at 11 feet high and has a hydraulic height of 7.2 feet, providing a storage capacity of 400 acre-feet. The reservoir serves primarily for irrigation and water supply purposes, drawing water from the Wfk Rock Creek and covering a surface area of 80 acres.

Managed by the California Department of Water Resources (DWR) under the Safety of Dams program, Cummings Reservoir No. 1 is subject to state regulation, permitting, inspection, and enforcement. With a significant hazard potential, the dam's condition was last assessed as satisfactory in September 2017. The reservoir has a drainage area of 6 square miles and a maximum discharge capacity, although specific spillway details are not provided in the data.

Amidst the picturesque landscape of Modoc County, Cummings Reservoir No. 1 stands as a vital infrastructure for water resource management in the region. With its historical significance dating back over a century, this reservoir plays a crucial role in supporting agricultural activities and sustaining water supply needs for the local community. As climate change continues to pose challenges for water availability, the importance of maintaining and monitoring dams like Cummings Reservoir No. 1 for safety and sustainability cannot be overstated.