The Colorado River and Boulder

The Colorado River is a hot topic lately. Reports have mentioned climate change, drought, lower water levels and diminishing flows on the river. Here are some answers to commonly asked questions about how the Colorado River affects the City of Boulder's water supply.

Does Boulder's water come from the Colorado River?

Yes, some of it, but not all. The city gets its water from three different sources, which helps make Boulder more resilient to natural disasters and able to adjust its water sources as needed. The high-quality water sources come from both east and west of the Continental Divide, including Boulder Creek's headwaters and the upper Colorado River.

If the Colorado River dries up, how will it impact Boulder?

Our water supply still has reliability because we can obtain water from several water sources in cases of moderate, localized drought. If Boulder receives less water from the Colorado River, we may increase our reliance on the Boulder Creek basin water supply. Additionally, it may become increasingly important to conserve water.

What about climate change?

There's no doubt our climate is changing. Summers are getting hotter, and rain and snow are more unpredictable. These global changes are having an enormous impact on the natural systems around us. As our region becomes drier, native plants and animals may struggle to survive. Learn how to slow these trends by supporting living systems and participating in nature-based climate solutions.

What about drought?

Hotter temperatures and earlier snowmelt can create increasingly dry conditions. While we monitor water supply conditions year-round, we make a decision about whether to implement mandatory water use restrictions in early May. This determination is primarily based on snowpack levels in the mountains west of Boulder, reservoir storage levels and our allocation of water from Northern Water's Colorado-Big Thompson Project. The city's Drought Plan provides guidance for recognizing and responding to droughts that may affect water supply.

What steps is the city taking?

This year, record hot and dry weather is impacting water supplies across the region. Based on the current conditions as of April 1, 2026, the City of Boulder is entering a Drought Watch: asking for voluntary reductions in water use.

We also continually plan for long-term water resilience by investing in infrastructure, assessing the impact of different climate change scenarios and anticipating future water supply and demand. In addition to planning, our Water Conservation Program supports efficient and sustainable water use in the community by providing resources for efficient water fixtures, waterwise landscaping and irrigation system improvements.

What can I do?

Using water more efficiently and sustainably can help reduce Boulder's use of Colorado River water.

Outside the home: There are many ways to reduce outdoor water use, such as landscaping with waterwise plants that don't require much water and are better adapted to our changing climate, making sure irrigation systems are working properly, or watering plants during the coolest parts of day - before 10 a.m. and after 6 p.m.

Inside the home: Nearly one trillion gallons of water are wasted each year in U.S. homes in preventable ways. Many common household leaks are quick to find and easy to fix. In just 10 minutes, you can search your home for leaks that lead to water waste.

Learn more on the Water Conservation webpage

Header photo credit: Bureau of Reclamation