Water from the Barker Reservoir, Lakewood Reservoir and Silver Lake watersheds is either:
- drawn directly from Middle Boulder Creek or North Boulder Creek; or
- stored in Barker Reservoir, Lakewood Reservoir, Silver Lake Reservoir or another reservoir within the watersheds that are located on Middle and North Boulder creeks.
Water from the Boulder Reservoir and Colorado Big Thompson watersheds is either:
- delivered to the Boulder Reservoir Water Treatment Plant from the Carter Lake Pipeline
- stored in Boulder Reservoir.
The City of Boulder owns approximately 26,000 acre feet of reservoir storage capacity for its system. The city's ability to obtain water from both east and west slope sources provides a measure of water service reliability in response to moderate, localized droughts.
Barker Reservoir, located on Middle Boulder Creek, is owned by the City of Boulder. Water from Barker Reservoir is treated, along with the Silver Lake Watershed supply, at the Betasso Water Treatment Plant.
Completed in July 2002, the Middle Boulder Creek Water Source Management Work Plan provided and evaluated information about the Barker system and the Middle Boulder Creek watershed. Based on the information collected, the work plan recommended management decisions for the future. The work plan is dynamic and flexible, and will evolve as more is learned about the Middle Boulder Creek watershed.
Each year, typically between mid-May and June, the Barker Reservoir spills over due to runoff from melting mountain snow. This is a normal and expected event that increases flows in Boulder Creek and residents are urged to take caution around the creek.
Boulder Reservoir, located northeast of Boulder, Boulder Reservoir was built by the city to provide another source of drinking water. Boulder Reservoir has also become a popular recreation site. Boulder Reservoir is owned by the City of Boulder, but is operated by Northern Water.
Northern Water also operates the Colorado-Big Thompson (CBT) Project and the Windy Gap Project. These two projects divert water from the upper Colorado River on the western slope and deliver it through a series of tunnels, canals and reservoirs to northeastern Colorado cities, farms and industries. Most of the water in Boulder Reservoir comes from the CBT and Windy Gap Projects via Carter Lake, although runoff from local drainage basins also adds to the water supply. Before the water in Boulder Reservoir is used for municipal purposes, the water is first treated at the Boulder Reservoir Water Treatment Plant.
Lakewood Reservoir is primarily fed by water from the city-owned Silver Lake Watershed via the Lakewood Reservoir Pipeline, but may also receive water from North Boulder Creek and Como Creek.
Melting snowpack during the spring and summer months is captured in Silver Lake Reservoir. The amount of water that is available for community use varies from year-to-year and depends on the level of snowpack in the surrounding mountains.