The Colorado River: Why is it so important to us?

The Colorado River is the lifeblood of the Southwest. Cutting through 1,450 miles of mountains and deserts, it supplies water to 40 million people and irrigates 5.5 million acres of farmland; that’s 15% of the nation’s crops and 13% of the nation’s livestock feed. The River and its tributaries support a multi-billion dollar recreational economy—boating, fishing, birding, hiking and hunting are among attractions that draw tens of millions of enthusiasts from around the world.

Major Source Nineteen states and Mexico rely on Colorado River water. A significant portion of the population and agriculture in the South Platte River and Arkansas River basins (that’s us!) is sustained by imported water from the Colorado River Basin.

70% of the water used by Colorado Springs residents started as Colorado River water! Diversions in the upper Eagle River and Blue River watersheds collect water and convey it through tunnels under the Continental Divide. From there it is carried in stream channels and pipelines to our system of reservoirs and then on to our water treatment plants. Our Colorado River

supplies are especially valuable because we use that water multiple times by trading that portion treated in our wastewater treatment plants for more water from the Arkansas River and Pueblo Reservoir.

Major Threats The Colorado River has long been under intense pressure for development and management from competing interests. Starting in 1922 the Colorado River Compact and associated subsequent agreements were developed to allocate Colorado River water according to specified formulas among seven western states (the lower basin states of Arizona, California, and Nevada and the upper basin states of Colorado, New Mexico, Utah, and Wyoming) and Mexico. The Compact requires the Upper Basin States to release enough water to the Lower Basin States below Glen Canyon Dam (Lake Powell) to maintain a 75 maf 10-year rolling average. If shortages occur due to extended drought, Colorado and other Upper Basin States may have to reduce their Colorado River water uses, and Colorado Springs and other Front

Range cities would have to reduce or eliminate their Colorado River transbasin diversions.

Population growth, agriculture use, energy development, climate variability and over a decade of consecutive drought years have stretched water supplies in almost every part of the Colorado River Basin. The appropriation of water under the

Colorado River Compact exceeds the amount of streamflow that has occurred over the past few decades, meaning not all states may be able to get their full Compact entitlement every year. Additionally, not every State (including Colorado) has developed its full apportionment. Although the large amount of water storage in Lake Powell, Lake Mead, and other reservoirs in the Colorado River Basin helps meet demands in dry periods, the threat of shortage is still a concern under current conditions. Various Basin States have developed plans for how to manage shortages if and when they occur.

Threats to Colorado River supplies are only expected to increase. Under future climate assumptions, sometime in the next 100 years, U.S. Bureau of Reclamation models of Colorado River Basin indicate that there is a significant chance that stream flows will be insufficient to support all municipal and agricultural demands and Compact obligations without a curtailment of Upper Basin State uses.

The Colorado River system relies on two large regulating reservoirs: Lake Powell in the Upper Basin and Lake Mead in the Lower Basin. While the Upper Basin is in good shape in terms of meeting its 10 year moving average obligation there are other concerns in the Colorado River Basin. Electric power generation from Glen Canyon Dam at Lake Powell helps supply the electrical needs of 5.8 million people, including a significant number of people in Colorado, including Colorado Springs. Severe drought since 2000 and a supply-demand imbalance in the Lower Basin have caused both reservoirs to approach very low levels.

A few more years of persistent drought could jeopardize the power source for millions of people as storage in Lake Powell may drop below the level at which the reservoir can generate hydroelectric power. For the same reasons, Lake Mead storage could drop below the first water intake for the city of Las Vegas, affecting millions of residents and a significant portion of our region’s economy.

Environmental and recreation needs (sometimes called non-consumptive uses because they rely on water that is left in the streams) have become a greater management priority, and could limit our ability to make future diversions from the West Slope. Colorado has not developed its full entitlement yet, but as our demands increase we will put more of our available Colorado River water to beneficial use. An increased reliance on Colorado River supplies will increase our water supply risk if those supplies are not reliable or sustainable.

Our Response Denver, Aurora, and other Front Range communities from Pueblo to Fort Collins rely on Colorado River water. Front Range cities, including Colorado Springs Utilities, have a large stake in the future of the Colorado River and how challenges of increasing population, long-term drought, competing uses, and climate change will be addressed. We are actively involved in numerous planning efforts and studies related to sustainability of Colorado River Basin supplies, and are closely monitoring the ongoing discussions between the Upper and Lower Basin States, the Federal

Hoover Dam and Lake Mead on the Colorado River, showing current low water level

Government, and other stakeholders on issues involving the Colorado River. Examples of regional studies in which Colorado Springs Utilities participates include:

» A State-sponsored investigation of a Colorado River Water Bank (a method of facilitating short term sharing of water between West Slope agricultural water users and East Slope cities);

» Participation in a stakeholder group developing alternatives to proposed Wild and Scenic designations in the Colorado River Basin that would provide flexibility to water providers; and

» Development of a Colorado State Water Plan that will address issues around West Slope – East Slope water transfers.

Our ongoing Integrated Water Resources Plan (IWRP) has identified Colorado River shortages as a key threat to our future water supply sustainability, and we are investigating possible solutions to mitigate the impacts of those shortages. For more information on the IWRP and other Colorado Springs water planning issues, visit the Colorado Springs Utilities website at https://www.csu.org /Pages/iwrp-r.aspx.