Stinky Warm Spring
Stinky Warm Spring earns its name from hydrogen sulfide gas that gives the 88-degree water a distinct rotten-egg smell, a common signature of geothermally heated water passing through sulfur-bearing rock. This roadside feature near McCall sits at 3,410 feet in Valley County with easy access just 240 feet from the road.
The spring emerges at a low enough elevation to sit below the heavy snowpack zone, though the area still receives nearly 153 inches of snow annually. Sulfate levels reach 190 mg/L and sodium hits 130 mg/L, creating moderately mineralized water with an alkaline pH of 8.8. The smell announces the spring before it comes into view. At 40 degrees above ambient, the water feels tepid rather than hot. Surrounding forest and the relatively low elevation give the area a different character than the alpine springs scattered across the higher peaks of Valley County.
The spring's chemistry reflects water that has circulated through volcanic rocks containing sulfide minerals, picking up hydrogen sulfide gas along the way. USGS measurements recorded 30 degrees Celsius at the source. The low sodium-to-chloride ratio and elevated sulfate levels distinguish this from the deep-circulating granitic springs found farther east. Valley County sits at the intersection of several geological provinces, producing thermal features with widely varying chemistry within short distances.
Park roadside and walk about 240 feet to the spring. The sulfur smell is strong and may bother some visitors. The 88-degree temperature is below comfortable soaking range for most people. Grouse Campground at Goose Lake sits about 8.5 miles away and accepts reservations. The spring is most interesting as a geological curiosity rather than a soaking destination. No facilities at the site.
Is Stinky Warm Spring worth visiting?
Best for
- Warm-water soaking
- Easy day trips
- Overnight camping trips
The water at Stinky Warm Spring is alkaline (pH 8.8).
Overview Grouse Campground is located just 16 miles from McCall, Idaho, on the shores of Goose Lake. Visitors enjoy canoeing, fishing and horseback riding. Once on-site, you may be able to pay for your campsite(s) by scanning a QR code using the Recreation.gov mobile app, and the Scan and Pay feature. If this option is available, you will need to first download the free Recreation.gov mobile app https://www.recreation.gov/mobile-app prior to your arrival as some remote areas have limited or...