Here’s some need-to-know information for the week:
Barker Reservoir to fill and spill soon
Each spring as temperatures warm, stream flows increase due to runoff from melting mountain snow. Before peak stream flows occur at lower elevations (like in the city of Boulder), mountain reservoirs must first fill and start spilling.
Barker Reservoir is expected to start spilling in the next week or two. This is a normal and expected event, which will increase flows in Boulder Creek throughout the city. Barker spill typically occurs sometime between mid-May to late June, with the exact date dependent on weather, snowpack and early spring reservoir levels.
Like all the city’s water supply reservoirs, Barker Reservoir provides a source of drinking water, and its operation (storage and release timing) is dictated by water rights administration. Unlike flood control reservoirs that have extremely large storage volumes (e.g., Cherry Creek and Chatfield reservoirs), Barker Reservoir has relatively limited storage space, which means that when the reservoir is full, excess water passes over the spillway and continues flowing downstream into Boulder Creek. To provide a sense of scale, the volume of water that flows through Middle Boulder Creek each spring could fill the reservoir multiple times.
For more information about the city’s mountain reservoirs, contact Kim Hutton, Water Resources manager, at HuttonK@bouldercolorado.gov or 303-441-3115.