Unnamed Thermal Spring
Drag the handle to compare the two views. The orange dot marks the spring, in a frame about three quarters of a mile wide.
An unnamed thermal point under two miles outside Alturas, in Modoc County. Water comes out hot, right at the limit of what a person can sit in. The ground is BLM, run out of the Black Rock Field Office. Public access is open. There is a USGS number for the site and no chemistry to go with it.
A short walk, a few hundred yards, from a road with no recorded name. Elevation is moderate. Winters are snowy, close to three feet over the season, and the year brings something like eleven inches of rain and snow combined. No campground is recorded. Town is close.
The record points to December through February as the best stretch. Hot enough water that a hand test comes before anything else. No fee is listed, no campground either. Access is marked open, and the Black Rock Field Office is the place to ask about anything more.
Aircraft with laser scanners measured this ground to within inches. The scan strips out trees and buildings, leaving the bare shape of the land around this spring.
- Setting
- Hillside
- The spring sits on a steep slope that climbs to the northwest.
- Highest ground nearby
- 183 ft above the spring
- Within a quarter mile, to the northwest
A slice through the ground from west to east, about 0.6 miles end to end.
Elevation data: USGS 3D Elevation Program. Aerial imagery: USGS The National Map. Public domain.
That's about twice the US average of 65. It's higher than at 74% of the springs on this site.
Heat flow measures the warmth working its way up through the ground from deep inside the earth. Where it runs high, rain and snowmelt that seep down through cracks in the rock come back up hot.
See every spring on the geothermal heat map →
Heat flow estimate: Stanford Thermal Earth Model (Aljubran & Horne, 2024), CC BY 4.0.