Old Homestead Warm Spring
Old Homestead Warm Spring barely qualifies as thermal, emerging at just 59°F near Weiser in Washington County, Idaho. With a trickle of 0.01 cubic feet per second at 2,820 feet elevation, this is one of Idaho's most marginal warm springs, interesting more for its chemistry than its bathing potential.
The spring seeps out in the dry foothills east of Weiser, where western Idaho's arid valleys receive just 12 inches of annual precipitation and less than two feet of snow. The landscape is dominated by bunchgrass and sagebrush at this low elevation, with scattered draws cutting toward the Snake River drainage. Summer temperatures push well above the spring's 59°F output, meaning the water actually feels cool during warm months. An 820-foot walk from the road crosses open, exposed ground with little shade.
The spring's near-neutral pH of 7.9 and balanced mineral content (calcium 20 mg/L, sodium 24 mg/L, sulfate 22 mg/L) suggest shallow circulation through mixed sedimentary rock rather than deep geothermal sourcing. Its 15°C temperature barely exceeds the local mean annual air temperature of 53°F (12°C), placing it at the threshold of thermal classification. The minimal 0.01 cfs discharge indicates a small, possibly seasonal flow path.
Mann Creek Campground, about nine miles away, is reservable and sits near Mann Creek Reservoir, a popular boating and fishing spot. The spring itself offers no soaking opportunity given its 59°F temperature and negligible flow. It holds interest mainly for geology enthusiasts and spring catalogers. The area is accessible year-round given its low elevation and mild winters. Bring water, as no facilities exist at the spring.
Is Old Homestead Warm Spring worth visiting?
Best for
- Overnight camping trips
The water at Old Homestead Warm Spring is slightly alkaline (pH 7.9).
Overview Mann Creek Campground is located near the Mann Creek Reservoir in the foothills of the West Central Mountains in western Idaho near the Payette National Forest. The reservoir is a popular boating and fishing destination. 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....