Introduction: Hot springs contiune to be one of my favorite natural features. I am always amazed that water can flow out of the Earth 24/7, seemingly endlessly. Soaking in the hot springs is even better. Often, they even provide therapeutic benefits.
History: San Juan Hot Springs was privatley owned and operated as a resort until 1992. The resort was founded in the late 1800's, with several buildings. These included a dance hall, general store, and lodging for overnight stays.
Getting there: Ownership of the land changed hands many times between the resort and now. After many years of the site being a hotspot (quite literally with 122 degree water!) for illicit activity, Ortega Hwy bisecting the resort, and the county raising rent, the resort shut down and was demolished. Since then, OC Parks owns and maintains the property as part of Caspers Wilderness Park. The main (easy) access to these springs is now off-limits, with the county advising people to access the springs via a 10-mile hike beginning at Caspers. I have marked the trailhead for the San Juan Creek Trail as a waypoint, and made the terrain rating reflect the daunting hike. Parking at the fire station and entering the easy way requires trespasing, and I have personally seen rangers out that way on multiple occasions. However, if hiking all the way in from the park, the springs are accessible and you will have no problem viewing them!
At this site, we will cover the geology of hot springs, and what makes them possible.
Hot springs are geothermal, which means the water is heated by the Earth, not an external source. A large percentage of the natural hot springs that are not in volcanic zones, such as this one, are heated by the breakdown of natural, radioactive elements in the Earth's mantle.
Temperature of subterranean rocks increases with depth, so the further down water travels, the higher it will be heated. This is known as the geothermal gradient.
Next, hot springs often have high concentrations of minerals in the waters themselves. These minerals include sulfur, magnesium, iron, and borax. Back in the day, in was common to tout these mineral-rich waters as having healing powers for a variety of ailments. Although true to a limited extent, many of these effects were exaggerated for business opportunities. These waters have so many minerals because as the scalding water rises to the surface through cracks and fissures, it dissolves the surrounding rock it comes into contact with. Therefore, the minerals found in hot springs are directly representative of what minerals can be found in the surrounding bedrock. These dissolved minerals can also end up being deposited along or in the springs themselves, creating fun colors and interesting patterns on the rocks. It also can create quite the smell, primarily due to the sulfur deposits.
Whether hot springs can cure you of certain ailments or not, there is no debating their magical aura and their effects on at least improving mood. Keep in mind, however, that you should never submerge fully underwater in hot springs, due to bacteria that thrive in the hot water. Similarly, if you have nay open cuts or sores, bacteria can easily infect through those breaks in the skin surface. These particular springs have signs posted that state 'no swimming,' so I can not advise you to enter the water.
Just be sure to not leave any trash (pack in/pack out).
Upon your return from the springs, please send a message with the following to earn credit for the Earthcache:
- The name of the Earthcache, along with the number of people in your group.
- Locate the source, where the water flows into the pools. Are there bubbles coming up? What is causing that?
- Do you notice any smell coming from the water? What mineral can this be attributed to?
Sources:
https://en.wikipedia.org/wiki/Hot_spring
https://www.britannica.com/science/hot-spring
https://www.kernvalley.com/news/hotsprng.htm
https://www.orangecountyoutdoors.com/get-out-there/historical-places/capistrano-hot-springs