
The Upper Colorado River watershed spans almost 2,000 square miles in north-central Colorado and is the headwaters for the mighty Colorado – one of North America’s most iconic rivers.
UCWET's target area is composed of nine sub-watersheds, all of which flow into the Upper Colorado.









In 2025, UCWET commissioned Lotic, a local environmental consulting firm, to conduct an environmental flow assessment of the Upper Colorado and Fraser River basins — quantifying how much water is currently flowing through Grand County and modeling the impact of proposed future diversions.
That same year, Grand Environmental Services completed an in-depth water quality analysis of the Fraser River, documenting elevated temperatures, low dissolved oxygen, excess nitrogen and phosphorus, and multiple stream reaches failing to meet state water quality standards. Long-term precipitation data for the region shows a steady decline in annual snowpack and runoff.
Together, these studies confirm what many have long suspected:
Reduced water quantity is directly worsening water quality in the Upper Colorado watershed.









A watershed is an area of land that drains into a given body of water – from a river or a lake to the ocean. Every raindrop that falls runs downhill until it reaches a larger body of water, with creeks turning into streams that combine to form rivers, which eventually flow into an ocean.
A watershed group is a locally-organized, volunteer-based nonprofit that seeks to educate, support, and connect the various stakeholder groups within a watershed with the scientific data and resources needed for effective watershed management. Watershed groups are nonpolitical and nonregulatory, with a focus on uniting local stakeholders in creating a sustainable watershed management plan that reflects the values and interests of those who depend on the watershed – including the surrounding ecosystem.
We all benefit from a healthy watershed. Established watershed groups are proven to improve water quality, with significant benefits for our local recreation-based economy and the surrounding ecosystem.

Colorado is a semi-arid state, averaging only about 17 inches of rainfall annually. It is also one of the fastest-growing states in the US, with over a million people moving here since 2010. While most of Colorado's population lives east of the Continental Divide – in Denver, Fort Collins, and Colorado Springs – most of the water falls to the west in the form of mountain snowpack. Meeting the daily water needs of its citizens has always been a challenge for the towns and cities east of the Rockies.
Transbasin diversions harness that water high in the Rockies and move it in the opposite direction – up and over the mountains, east to where the bulk of Colorado's population is found. Water that would have eventually reached the Pacific Ocean now flows into the Atlantic, drastically altering ecosystems and economies both where it is taken from and where it is taken to.
There are two transbasin diversions in Grand County: the pipeline running through the Moffat Tunnel near Winter Park Resort, and the Adams Tunnel near Grand Lake, the lynch-pin of the Big-Thompson Project.
Most of the water is diverted at around 9,000 feet – well before it reaches the watershed. Currently, approximately 60% of local flows are diverted out of the watershed through these two projects. The proposed expansion of Gross Reservoir outside of Boulder would increase diversions to 75% of flows in Grand County.

While several smaller nonprofits currently conduct restoration efforts on limited stretches of the Upper Colorado River basin, UCWET is the first collaborative, local effort to organize the diversity of stakeholder groups in one of the most critical headwaters in North America.
UCWET focuses on the watershed as a whole, providing a common forum and the information, education, logistics, and financial and technical support that stakeholders need to manage local water resources sustainably.
UCWET is also fighting to keep water flowing on this side of the Continental Divide.
With 60% of local flows already diverted east before that water even reaches the watershed, the proposed expansion of Gross Reservoir would push that figure to 75% – and that is unsustainable. With over 300 miles of impaired waters already in the Upper Colorado watershed, diverting even more of this vital resource will do irreversible damage to the lands, streams, and rivers that we all depend on. Summer water temperatures already reach critical levels through most of the watershed, making fly fishing in our world-renowned streams lethal to aquatic life during the hottest parts of the day.
Every drop counts.
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