From Snowpack to Sea: How Colorado Water Reaches the Ocean

By Katie Sheahan | April 17, 2026 

It’s been an unseasonably warm winter in Colorado, so I’m pretty happy to be writing this while watching the snow drifting in big, fluffy clusters through my windows. We haven’t had any precipitation lately; in fact, it’s been the warmest winter on record in Colorado with nearly the lowest recorded snowpack (except for 1976-77 and 1980-81), according to National Weather Service and Colorado Climate Center data. Getting this much-needed moisture mid-April has me thinking about what our rivers will look like this summer; if we’ll be able to go rafting and kayaking in pristine lakes and rivers like we’re used to in this state. I went down a rabbit hole about this with my family yesterday while discussing the decreasing availability of drinkable water around the world. If it’s not snowing in Colorado, and it won’t melt in the summer to feed our rivers, how will this affect our drinking water? How will it affect our oceans? Will we need to invest in desalination plants like we do gas stations? I wonder if any of the snowflakes I’m watching will end in the Pacific Ocean, or maybe the Gulf of Mexico…

The Maroon Bells, May 2021. Photographed by Katie Sheahan

Snowpack in Colorado acts like a kind of seasonal water bank. What falls in winter doesn’t disappear when it melts; it gets “stored” in mountains until spring and summer, when it slowly releases into rivers and groundwater systems. That gradual release is what feeds everything from alpine wetlands to major river systems like the Colorado, Arkansas, and Platte Rivers.

Those rivers don’t end in Colorado. They move through landscapes, communities, farms, and cities far beyond what we can see from here. The Colorado River alone travels through multiple states before eventually reaching Mexico, where it historically met the Gulf of California. Along the way, it is diverted, dammed, used, and reused. By the time it reaches the ocean, if it reaches it at all, it is a fraction of what it once was.

Blue Lakes Summer 2020. Photographed by Katie Sheahan.

This is where the connection between what I’m watching outside my window and the ocean becomes more tangible. Snow in Colorado is not just local weather; it is part of a continental-scale water system that ultimately influences ocean conditions. When snowpack is low, rivers shrink. When rivers shrink, less freshwater reaches coastal ecosystems. That can shift salinity levels, alter nutrient delivery, and change the balance of life in estuaries and nearshore environments where freshwater and saltwater meet.

It’s easy to think of the ocean as separate from this moment, especially when you’re standing in a place that feels so far from it. But the ocean is not disconnected from snowfall in the mountains. It is the endpoint of everything that moves downhill, through soil, through rivers, through infrastructure, and through human decisions about how water is used.

And then there’s the scale of it that’s harder to grasp: every snowflake I’m watching right now is part of a system that stretches far beyond Colorado. Some of this water will be pulled into irrigation systems and never leave the continent. Some will replenish aquifers. Some will evaporate and return to the atmosphere. And some of it, eventually, will make its way into the ocean, carrying with it whatever it has picked up along the way.

This is the part that stays with me. Not just the idea that water moves, but that it carries the imprint of everything it passes through. Landlocked doesn’t mean disconnected. It just means upstream.

Ocean view in Miami, May 2023. Photographed by Katie Sheahan.

Colorado Climate Center. February 2026 Colorado monthly climate summary.