Rocky Ridge, also known as Water Supply #1, is a privately owned irrigation dam located in Larimer County, Colorado, near Fort Collins. Built in 1940 by designer James C. Scott, this earth dam stands at a height of 16 feet with a hydraulic height of 35 feet, serving the primary purpose of irrigation along the Cache la Poudre River. With a capacity of 5,173 acre-feet and a surface area of 236 acres, Rocky Ridge plays a vital role in water resource management in the region.

The dam has a spillway width of 290 feet and a maximum discharge of 5,880 cubic feet per second, ensuring effective flood control measures. Despite being classified as having a high hazard potential, Rocky Ridge is in satisfactory condition based on the last inspection conducted in June 2020. The risk assessment for the dam is moderate, with no specific risk management measures identified in the data.

Overall, Rocky Ridge is a significant water infrastructure feature in Colorado, contributing to irrigation practices while also serving as a crucial element in flood control along the Cache la Poudre River. With its historical significance dating back to the 1940s and its continued operational relevance, this dam remains an essential component of the region's water resource and climate resilience efforts.