Dehy Hot Spring flows at an impressive 134°F (57°C) from BLM land near Mammoth Lakes, where water emerges 87 degrees above the ambient mountain temperature of 46.6°F. Located at 6,889 feet elevation in the Long Valley geothermal area, this substantial thermal anomaly represents significant geothermal resource potential.
The spring requires a walk of approximately 3,012 feet from Pit Road through high-altitude terrain where seasonal snow reaches 72 inches annually. The remote setting combines volcanic geology with high elevation forest, creating harsh conditions where the thermal spring provides an island of warmth in the alpine landscape.
History of Dehy Hot Spring
Dehy Hot Spring sits within the Long Valley geothermal system, a region of intense scientific interest due to earthquake history and geothermal activity. The spring emerges from deep thermal fractures in volcanic rock, representing groundwater heated by proximity to geothermal resources at depth.
The spring requires a substantial walk of roughly 3,000 feet and sits at 6,889 feet elevation, accessible only in summer and fall when snow clears the terrain. BLM land designation allows public access. Crowley Lake Campground 12.2 kilometers away offers 47 reservable RV and tent sites with potable water and dump station. Plan for alpine conditions with sudden weather changes.
Is Dehy Hot Spring worth visiting?
Best for
- Hot spring soaking
- Overnight camping trips
Dehy Hot Spring is well suited for hot spring soaking and overnight camping trips.
Annual Precip: 14.4 in
Annual Snow: 72.3 in
February
Air 29°F · Water 134°F · +105° contrast
December
Air 29°F · Water 134°F · +105° contrast
January
Air 30°F · Water 134°F · +104° contrast
February offers 39°F more contrast than July
Recent Temperature
98.6°F
(37.0°C)
Measured Aug 09, 1973
Discharge
0.1 ft³/s
Measured Aug 09, 1973
The water at Dehy Hot Spring is slightly alkaline (pH 7.7). It is notably rich in sodium (supports circulation and skin hydration) and chloride (natural antiseptic with skin health benefits).
pH influences mineral absorption through skin
May support bone density and joint health
Known for muscle relaxation and stress relief
Supports circulation and skin hydration
Traditionally used for skin conditions and inflammation
Natural antiseptic with skin health benefits
Iron-rich springs may support circulation
Overview
Crowley Lake Campground offers 47 RV/tent sites, maximum recommended RV length is 30 feet. All sites include a fire pit, picnic table and a lantern holder. No hook-up. Potable water is available. Dump station fee is $10.00, no passes accepted. Closest amenities are 2 miles south in Crowley, or 10 miles north in Mammoth Lakes.
Recreation
Popular activities include lake and stream fishing, boating, windsurfing, horseback riding, hiking, and wildlife viewing.
Facilities
Crowley Lake...
Reserve on Recreation.gov →
Swimsuit & towel
Water bottle
Stay hydrated, especially in hot water
Camping gear
Nearby camping at Crowley Lake Campground
Trash bag
Pack out what you pack in
Water shoes
Hot ground near source
31 miles from Mammoth Lakes, CA
USGS Quad: (MT. MORRISON 15) · Circ 790: 56.0 · NOAA: 6.0 · AMS Map: MARIPOSA
What is the water temperature at Dehy Hot Spring?
Dehy Hot Spring has a water temperature of 134°F (57°C). This is considered a hot spring, well above body temperature.
Where is Dehy Hot Spring located?
Dehy Hot Spring is located in Mono County, California at 6,889 feet elevation, near Mammoth Lakes. Coordinates: 37.6770°N, 118.7900°W.
How do I get to Dehy Hot Spring?
Dehy Hot Spring has Short Walk road access, with the nearest road being Pit Road (0.6 mi from the road).
Is Dehy Hot Spring free to visit?
Dehy Hot Spring has Open access. It is managed by Bureau of Land Management.
Can I camp near Dehy Hot Spring?
Yes, Crowley Lake Campground is located nearby (7.6 miles away).
What minerals are in the water at Dehy Hot Spring?
Water chemistry analysis shows the presence of pH, Calcium, Magnesium, Sodium, Sulfate, Chloride, Iron. The pH is 7.7 (slightly alkaline).
Is it safe to soak at Dehy Hot Spring?
At 134°F, Dehy Hot Spring is hot enough to require caution. Enter slowly, limit soaking sessions to 15–20 minutes, and stay hydrated. Always tell someone your plans before visiting remote hot springs.
Is Dehy Hot Spring crowded?
Dehy Hot Spring sees varying levels of visitors depending on the season and day of the week.
What should I bring to Dehy Hot Spring?
Essentials for Dehy Hot Spring: swimsuit, towel, water bottle, camping gear, a trash bag to pack out what you pack in. The water is over 110°F — test the temperature before entering and watch for scalding near the source.