After delays related to both low water levels and staffing shortages, the Union Reservoir Swim Beach will open on Monday, July 28, 2025, at 10 am.

Union Reservoir, located at 461 County Road 26 in Longmont, is a 736-acre body of water providing many outdoor recreational activities in addition to the swim beach. Union Reservoir began 2025 at half water capacity. Following a safety review by recreation staff, park rangers, and Risk Management, the City delayed opening the swim beach. As water levels began to reach viable levels, lifeguard-related staffing shortages prevented an immediate opening.

On July 28 the beach will open and will remain open daily through August 12, with hours from 10 am to 5 pm Monday through Thursday, and 10 am to 6 pm Friday through Sunday. One exception will occur on Sunday, August 10 when the swim beach (and all of Union Reservoir) will open at 1 pm following a Triathlon.

From August 16 through August 31 the beach will be open on weekends only, Saturday and Sunday, from 10 am to 5 pm. The beach will also be open on Labor Day, Monday, September 1, from 10 am to 5 pm.

“We’re so pleased to open the beach this week,” said Longmont Recreation Area Supervisor Sara Taylor. “While the delayed opening created staffing challenges as lifeguards found other summer work, staff really stepped up to train in new hires and resolve the problem quickly.”

For the latest information on Union Reservoir, visit bit.ly/union-res or reach out to staff at 303-772-1265 or union@longmontcolorado.gov.