Water Supply and Planning
Like most Colorado communities, Boulder depends on stored water during most of the year. High streamflows and runoff from melting snowpack only occurs during a few spring and summer months. The runoff from snowmelt is captured in a series of reservoirs. The amount of water that is available for community use varies from year-to-year, depending on the snowpack in the surrounding mountains.
On average, the majority of the city’s annual water supply comes from:
- Silver Lake and Lakewood reservoirs on North Boulder Creek;
- Barker Reservoir on Middle Boulder Creek; and
- Boulder Reservoir.
In general, the Silver Lake, Lakewood and Barker reservoir supplies are used as much as possible every year without reducing drought reserve supplies.
As Boulder continues to grow, the percentage of water delivered directly through the Boulder Reservoir Water Treatment Plant is projected to increase to about one-third of the city's total water supply, on average. The city currently owns enough additional water at Boulder Reservoir to meet all of Boulder’s future needs.
The City of Boulder's Drought Plan provides guidance for recognizing droughts that will affect water supply availability and for responding appropriately to these droughts.
The city uses rules and regulations to provide specific details that the city manager, in consultation with City Council, may use to declare or lift a drought alert stage as well as guide an appropriate response to a drought event.
Like many front range municipalities, one of the ways the City of Boulder manages the year-to-year variation in water supply is through its agricultural water leasing program. The city’s water supply is largely driven by annual precipitation, particularly snowmelt, which varies from year to year. In average or above average supply years, the leasing program allows the city to make surplus water supply available to other users.
Utilities’ Water Resources work group manages the city’s annual water leasing program, which primarily serves agricultural lessees for single year leases of Colorado-Big Thompson (CBT) water. Each year, on Jan. 1, city staff begins accepting lease requests from prospective lessees. In June or July, depending on whether the city’s Boulder Creek reservoirs are full, annual water leases are offered to lessees based on the order the lease requests were received and with priority given to water users in Water District 6 (Boulder Creek basin). Once lease agreement documents are signed and payment is made to the city, arrangements are made to deliver water to the lessees. Lease rates are set annually and can be found in Boulder Revised Code Section 4-20-25(d).
One unique type of lease involves augmentation water, which requires fully consumable water rights and typically requires a long-term commitment to meet the lessee’s needs. Due to water rights limitations and administrative burden, the city is currently unable to offer augmentation leases as part of the leasing program.
To learn more about water leases or to request an annual CBT lease, please contact Kim Hutton at (303) 441-3115 or [email protected]