Sharkey Hot Spring runs at 126 degrees Fahrenheit on BLM land in Lemhi County, just 286 feet from National Forest Development Road 185. Recent USGS sampling measured it even hotter at 146 degrees with a pH of 8.0 and sodium levels of 270 mg/L — among the highest sodium concentrations in Idaho's thermal springs.
The spring sits at 5,440 feet in the dry, open landscape near Salmon, where sagebrush and bunchgrass stretch across rolling hills. Annual precipitation is under 19 inches, giving the area a semi-arid character unusual for Idaho hot springs. Mineral deposits stain the ground near the source, and the sulfate-rich water carries a faint mineral smell. The Salmon River corridor opens to the west with wide valley views.
History of Sharkey Hot Spring
This section of Lemhi County lies along the Lemhi Range, where deep faults channel geothermal water to the surface. The water chemistry — high sodium, elevated sulfate, low calcium — points to prolonged contact with volcanic rock at depth. The BLM has maintained open access to the spring, which sits on public land managed through the Salmon Field Office.
The spring is roadside, accessible by vehicle via NFDR 185. Water emerges dangerously hot at the source, so test carefully and look for any cooled pools downstream. Agency Creek Campground is about 8 km away along the Lewis and Clark National Backcountry Byway, with a 14-day stay limit. No reservations needed.
Is Sharkey Hot Spring worth visiting?
Best for
- Hot spring soaking
- Easy day trips
- Overnight camping trips
Sharkey Hot Spring offers an accessible hot spring experience — great for a day trip.
Annual Precip: 18.8 in
Annual Snow: 77.8 in
December
Air 17°F · Water 126°F · +109° contrast
January
Air 19°F · Water 126°F · +107° contrast
February
Air 21°F · Water 126°F · +105° contrast
December offers 51°F more contrast than July
Recent Temperature
146.3°F
(63.5°C)
Measured Aug 05, 1980
The water at Sharkey Hot Spring is slightly alkaline (pH 8.0).
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
Agency Creek Campground (4 campsites) is located along the Lewis and Clark National Backcountry Byway, near the Lewis and Clark National Historic Trail and the Continental Divide National Scenic Trail. At the top of the pass, there is a memorial to Sacajawea. This secluded, arid area offers a variety of recreation activities including camping, biking, hiking, hunting, OHV riding, picnicking and wildlife viewing. Please be respectful of cultural and historical items found here.
Reserve on Recreation.gov →
Swimsuit & towel
Water bottle
Stay hydrated, especially in hot water
Warm layers
Cold air before and after soaking
Camping gear
Nearby camping at Agency Creek Campground
Trash bag
Pack out what you pack in
Water shoes
Hot ground near source
USGS Quad: GOLDSTONE MTN. 15 · PP 492: 60.0 · Circ 790: 106.0 · NOAA: 2.0 · AMS Map: DILLON
What is the water temperature at Sharkey Hot Spring?
Sharkey Hot Spring has a water temperature of 126°F (52°C). This is considered a hot spring, well above body temperature.
Where is Sharkey Hot Spring located?
Sharkey Hot Spring is located in Lemhi County, Idaho at 5,440 feet elevation, near Salmon. Coordinates: 45.0130°N, 113.6050°W.
How do I get to Sharkey Hot Spring?
Sharkey Hot Spring has Roadside road access, with the nearest road being National Forest Development Road 185 (286 ft from the road).
Is Sharkey Hot Spring free to visit?
Sharkey Hot Spring has Open access. It is managed by Bureau of Land Management.
Can I camp near Sharkey Hot Spring?
Yes, Agency Creek Campground is located nearby (4.9 miles away).
What minerals are in the water at Sharkey Hot Spring?
Water chemistry analysis shows the presence of pH, Calcium, Magnesium, Sodium, Sulfate, Chloride. The pH is 8.0 (slightly alkaline).
Is it safe to soak at Sharkey Hot Spring?
At 126°F, Sharkey 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 Sharkey Hot Spring crowded?
Sharkey Hot Spring is accessible from a paved road, making it easy to reach. Weekends and holidays may be busier — consider visiting on a weekday for a quieter experience.
What should I bring to Sharkey Hot Spring?
Essentials for Sharkey Hot Spring: swimsuit, towel, water bottle, warm layers for before and after soaking, 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.