Have you ever wondered how water gets to the Ouray Hot Springs Pool?

Many of you have asked, “Where does the water come from for the Ouray Hot Springs Pool?” Curious about how we manage the temperatures and why we don’t have the signature sulfur smell that other hot springs have? “What is the temperature before it comes to the pool? Do you add chlorine to the water? Why doesn’t it smell?” In this month’s blog we will give you some information about all of this. The hot springs water in Ouray starts as rainfall on the surrounding peaks. This water percolates deep into the earth, starts to heat up geothermally and picks up minerals along the way. When it encounters a major fault, like that in Box Canon Falls Park, it finds a quick way back to the surface, retaining its heat and minerals. The rotten egg smell is caused by hydrogen sulfide. Sulfur itself doesn’t have an unpleasant smell but anaerobic bacteria deep in the earth convert sulfur into hydrogen sulfide and it emerges with that unmistakable stink.  Ouray’s water doesn’t reach the depth where this happens so you get all the health benefits of dissolved sulfur without the smell.


  1. Box Canon Line- This is our main hot water source. The Box Canon Line originates at the Box Canon Falls on the southwest side of town and this line was the sole source from the 1920s until the 1980s. While the water flows vary throughout the seasons, the water temperature is a consistent 145-150 degrees at the source. The Box Canon line consists of two major and one minor spring originating in Cañon Creek Gorge approximately 100 yards below Box Cañon Falls.  The source furthest upstream on the east side is behind a cemented portal of an old mine. The next major spring is on the west side of Cañon Creek approximately 200 feet downstream of the portal and is encased in a concrete vault.



2.  OX2 Line- This is our secondary water source. This line originates behind the baseball field in Fellin Park. This line typically flows at a temperature of 120 degrees. In the 1980s this supplemental water from well OX-2 in the ballpark became available. The energy from the Pool Line Springs is insufficient to heat the pool in winter months, and until the drilling of OX-2, the pool was operated seasonally. Since the 1980’s the pool has been operational year-round.





3.  Ball Park Line- This is a supplementary line that is fed from the underground aquifer in the park into the Box Canon Line line before it reaches the pool. The Ball Park Spring source is from the east hillside in the vicinity of 10th Avenue and Main Street and is currently being added to other sources that flow into the pool. Flow and temperature vary seasonally, but the temps flow approximately 94-106°F.


Pre Filter Vault

These three water sources converge together at the pre-filter vault located just outside the pool fence near the fish pond (fenced area with the two white structures). The pre-filter vault is the first point at which we begin to treat the water before it enters the pool. There are two main areas within the pre-filter vault:



  1. Mixing Vault– This is where all three sources combine for the first time. The average temperature of all three lines coming into the mixing vault is 120-130 degrees at a rate of 200-300 GPM. Due to high manganese and iron concentrations within the natural mineral water, we pre-treat the water with liquid chlorine (if we did not do this, the pool water would turn a rusty brown color ((Iron Oxide)).
  2. Pump Vault– Once the water is mixed and treated with chlorine, the water is pulled from the mixing vault into the pump vault. Inside the pump vault is our main motor and pump for the entire pool. This motor and pump run 24 hours a day, seven days a week pumping water through our filtration system and then out to the pool.


Stay tuned for more information on how the pool operates as well as what changes are in store during the Renovation Project. Please let us know what questions you have about the past, present, and future of the Ouray Hot Springs Pool!

Article Written By Debbie Senft (Lead Cashier)