Unnamed Thermal Spring
At 2,730 feet in Owyhee County BLM territory, this spring produces 145°F (63°C) water with extreme alkalinity: pH 9.5, the highest documented in this dataset. Chemistry shows 0.93 mg/L calcium, 0.01 mg/L magnesium, 150 mg/L sodium, 89 mg/L sulfate, and 18 mg/L chloride, indicating deep circulation through Tertiary volcanic sequences.
The spring emerges in canyon country where basalt flows and rhyolitic tuffs create a landscape of cliffs, talus slopes, and narrow drainages. Located just 100 meters from the nearest road, the site sits at relatively low elevation compared to surrounding uplands. Annual precipitation totals 12.1 inches with 23 inches of snow; average air temperature of 56.2°F reflects the moderating influence of lower elevation. Vegetation consists of big sagebrush, rabbitbrush, and scattered juniper, transitioning to greasewood in drainage bottoms.
The 1980 NOAA inventory documented this spring without cultural or development history. The absence of a recorded name suggests minimal historic use, though the proximity to Leslie Gulch—a destination for rockhounds since mid-20th century—may have brought occasional visitors to the thermal feature.
Accessible year-round via short walk from vehicle, though summer heat exceeds 100°F. The pH 9.5 water can cause skin irritation; limit contact time. Slocum Creek Campground, 19 km distant near Lake Owyhee, provides base camping for exploring Leslie Gulch and this spring. Bring detailed BLM maps as roads are unmarked. The extreme alkalinity makes this a study site rather than soaking destination.
Is this spring worth visiting?
Best for
- Overnight camping trips
The water at This spring is alkaline (pH 9.5).
Nestled in a side canyon near the mouth of Leslie Gulch, Slocum Creek Campground makes a good base for gulch explorations. Cool off in the waters of nearby Lake Owyhee or hike the Leslie Gulch Area of Critical Environmental Concern. The campground includes nine campsites, eight of which contain some accessible amenities. The low light of early morning and late evening transforms the abutting rock outcrops of Slocum Creek Wilderness Study Area into magnificent fiery wonder.Know Before You GoCa...