Managing water supply and demand
Southwestern cities and agricultural users of Colorado River water are grappling with a river system out of balance. Large storage reservoirs such as lakes Powell and Mead filled in the decades before the Millennium Drought (2000-present) and were intended to equalize between above-average and below-average water years to make a variable water supply more reliable. But now, reservoir storage is dropping steadily, and no longer rebounds in near-average years as drier soils take a larger share of our snowpack before its melt can reach the river.
Locally, a trend towards lower streamflows in summer is causing high water temperatures and stressing fish. Lower streamflows mean more water from local reservoirs will be needed to keep streams healthy and meet the needs of our community. This increased pressure on reservoir storage will diminish our ability to withstand back-to-back drought years, increasing the risk of water supply shortages where there is insufficient water to meet all needs, especially the irrigation of outdoor landscaping.
Large cities and agricultural producers that use water from the Colorado River system are cutting back their total use to help balance the system. And so will we. Our community must reduce our take from local streams to come into balance with less water. Our local streams are both the source of our drinking water and the water that sustains aquatic health and recreation, the very essence of our headwaters community.
Some will point to population growth and development pressures as the cause of declining streamflows. This is not the case. The number of dwelling and commercial units served by our public water systems, the Eagle River Water & Sanitation District and Upper Eagle Regional Water Authority, increased by 25% since 2002, whereas the total water supplied to customers decreased by 6% in the same period. Growth is not the problem; the problem is a climatic trend toward drier conditions.
Ninety percent of the impact of our customers’ water use on streamflows comes from outdoor irrigation. Unlike indoor water use that is treated and returned to the river where it supports the aquatic environment and can be diverted and used again and again downstream, most water used on landscaping does not return to the river and cannot be reused, reducing local streamflows and the total supply available to our community.
Thus, our conservation efforts focus on outdoor water use by customers connected to our public water systems. Local golf courses do not use the public water system; they use their own water rights.
To encourage outdoor water conservation, we will implement a water budgeting system. A water budget will eventually be assigned to every account, designed to accommodate the specific needs of the property served. We will begin with single-family and duplex residential customers because these customers account for most of the outdoor water use.
Your budget will provide sufficient water to meet indoor needs year-round. During the growing season, your budget will be enough to adequately maintain a mix of smaller, discrete turf areas along with drip-irrigated areas and native and drought-tolerant species. We will implement a new rate structure that incentivizes alignment with the budget. Under this new program, the cost of your indoor and outdoor use within your budget will be billed at lower rates than water use beyond your indoor/outdoor budget, which will be billed at increasingly expensive rates.
Water budgeting incentivizes customers to use water within the means of our water supply. Because this may require landscaping modification for some customers to meet their budgets, we’re offering rebates to partner with you in these conversions. As you consider how your watering regimen can align with your water budget, we ask that you consider converting high-water-use turf to low-water-use grasses or native species, converting spray irrigation to drip for trees and shrubs, and prioritizing trees which can reduce your outdoor requirement by shading landscaped areas. Information about turf removal and other rebates is available to our customers via their WaterSmart account. And to ensure that your water-efficient landscape is also a fire-wise landscape, refer to fire-resistant landscaping recommendations from Vail Fire and Colorado State University.
Together we can bring our community’s water use into balance and mitigate the risks posed by a drying climate.
Dick Cleveland and George Gregory are the board chairs of Eagle River Water & Sanitation District and Upper Eagle Regional Water Authority, respectively.