Boulder - South is a vital water resource infrastructure located in Boulder, Colorado, designed for water supply purposes including irrigation, recreation, and water supply. This earth dam, completed in 1955, stands at a height of 45 feet and has a maximum storage capacity of 17,700 acre-feet. The dam encompasses a surface area of 684 acres and serves a drainage area of 14 square miles, with a spillway width of 1644 feet for uncontrolled discharge during high water events.

Managed by the local government, Boulder - South is regulated by the Colorado Division of Water Resources, with state permitting, inspection, and enforcement in place to ensure its proper functioning and safety. Despite being categorized as having a high hazard potential, the dam's condition assessment as of November 2020 was deemed satisfactory, with a moderate risk rating. Emergency action plans are in place, and regular inspections are conducted to uphold its integrity and mitigate any potential risks associated with its operation.

Located along Little Dry Creek, Boulder - South plays a crucial role in the water management infrastructure of the region, providing essential water supply services to the community while also offering recreational opportunities. With its strategic location and significant storage capacity, this dam serves as a key component in ensuring water resource sustainability and climate resilience in the Boulder area.