SJCA Guide to the

Animas River

Photo: Alex Pullen

Animas Riverkeeper Blast logo

We’re your Riverkeeper!

Marcel Gaztambide is your Animas Riverkeeper. He’s a full-time advocate for protecting and restoring the river’s health, ensuring safe, reliable access for recreation and promoting transparent and responsible water management.

The Animas River is born from snowmelt high in the rugged San Juan Mountains of Southwest Colorado, descending nearly 6,000 feet as it passes through Silverton and Durango, Colorado, Aztec, New Mexico and ultimately joins the San Juan River in Farmington, New Mexico.


The Animas River winds its way through spectacular gorges and sprawling valleys, offering thrilling white water adventures, mellow stretches of boating, Gold Medal fishing and spectacular scenery. It is used heavily for agriculture and increasingly for recreation, boating and fishing, which draws a substantial amount of tourism to the region. The Durango & Silverton Narrow Gauge Train, which travels along the Animas River from Durango to Silverton, alone draws nearly 200,000 riders a year.


Like many rivers in the American West, the Animas River faces some difficult challenges. Historic mining near the river’s mineral-rich headwaters has degraded water quality for more than 150 years, and was underscored, recently, by the Gold King Mine Spill of 2015.

Development within the river corridor, resource extraction, regional drought and a growing demand for water resources also present unique management challenges for the Animas River, highlighting the need for community involvement and smart river management.

What happened?

Gold King Mine Spill

On August 5th, 2015, as the EPA was investigating the Gold King Mine, workers accidentally released a whopping 3 million gallons of acidic metal-laden water into Cement Creek and the Animas River. Communities were stunned to watch their river run mustard yellow, carrying nearly 540 tons of metals all the way into the San Juan River and eventually Lake Powell.

Why did it happen?

Mining has played a major role in the San Juan Mountains for more than 150 years. While naturally high metal content and erosion have long contributed to pollution in the Animas River watershed, mining has greatly exacerbated the problem, significantly deteriorating water quality through acid mine drainage and heavy metal loading. Extensive mining in the region has left a complex maze of tunnels under the San Juan Mountains, the interaction of which are little understood. As the Environmental Protection Agency (EPA) worked to better understand the inner workings of the mine in the summer of 2015, they accidentally released millions of gallons of water that had built up behind the mine adit. The thick mustard yellow water poured down into Cement Creek below which carried it to the Animas River.

What’s being done?

Immediately after the Gold King Mine Spill communities all along the river united around the desire to pursue permanent clean-up of the headwaters through Superfund. The Bonita Peak Mining District was designated a Superfund site in September of 2016 and includes 48 historic mining-related sources of metal and sediment. Research and clean up is expected to take decades, but some early actions could begin in 2017.

What’s the State of the River?

This 2016 study of Animas River water quality by Mountain Studies Institute was encouraging. The data collected at Rotary Park in Durango, CO showed “no indication of any threat to human health from Animas River water and it does not appear that metal concentrations in 2016 were any higher than in previous years (2002-2014).”

It’s important to note, however, that the Animas River was heavily polluted from inactive mines prior to the Gold King Mine spill. Water quality is so poor downstream from Silverton that the river has been unable to support aquatic life upstream from Baker’s Bridge in Durango for many years. Below Baker’s bridge the river is artificially stocked with fish, which survive, but researchers have questions as to whether they can reproduce and maintain viable populations on their own.

What are we doing?
We’re the conservation voice at the table throughout the Superfund process, representing the river and the people and wildlife who depend on it. Outside of the Superfund process, we’re advocating for safe, reliable access for river recreation and the democratic management of the river’s water.


Whether it’s watchdogging Superfund cleanup of mine-impacted headwaters, supporting watershed research, or responding to citizen concerns, we are a dedicated, full-time advocate for the Animas River.


Strong river advocacy comes from personal connections to our waterways. Animas Riverkeeper supports responsible recreation for floaters and anglers between Silverton and Farmington.


Millions of taxpayer dollars fund the water districts that manage our water resources. We advocate for transparency, accountability, and the value of conserving water in the river for fish and wildlife.

Animas River Superfund Sites

Decades of mining at the headwaters of the Animas River have left a legacy of old mines, tailings piles, and contaminants. We’re working hard so that both the Animas and the communities that rely on it are healthy and vibrant. Use the map at the right to explore the mine sites and see what still needs to be cleaned up.

Current Status

Along with our watershed partners, we’ve formed an official Community Advisory Group (CAG) for the Bonita Peak Superfund site. For more information about the CAG, visit

Take Action!

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Learn More

We are involved in similar work for other rivers in the region. Check out our Rivers page for more information.

Recent News (More)

Protecting the Headwaters of the Animas River: Over 200 Comments Submitted

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The EPA proposed a new mine waste repository near Silverton, as part of their work at the Bonita Peak Superfund Site. We submitted our own SJCA comments on the proposal, and with your help sent in an extra 205 comments…
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CORE Act Passes the House!

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Colorado Passes Landmark Mining Reform Bill!

| Gold King Mine, Of Interest, Rivers | No Comments
This is a big step forward for protecting the rivers and taxpayer dollars in Colorado! While the federal 1872 Mining Law is still in desperate need of reform, this improvement for Colorado provides long overdue protections for our water resources…