Bat Hot Spring, Pence Hot Spring

Elmore County County, Idaho · Near Mountain Home Air Force Base
42.7970°N, 115.7230°W · 2,590 ft
117°F 2,590 ft Short Walk

Bat Hot Spring, also called Pence Hot Spring, surfaces at 117 degrees Fahrenheit in the desert canyons of Elmore County. Its alkaline water carries 243 mg/L dissolved solids with a pH of 8.2, producing a clean, mineral-light soak at 2,590 feet elevation.

A short walk of roughly a quarter mile from Hot Springs Road drops into dry canyon country carved through sagebrush and basalt. The air is thin and warm here, averaging 56 degrees Fahrenheit annually, with less than ten inches of rain. Desert varnish streaks the rock walls. The spring pools among boulders at the canyon floor, its thermal output a stark contrast to the arid landscape surrounding it.

History of Bat Hot Spring, Pence Hot Spring

This spring rises along fault lines in the western Snake River Plain, where volcanic activity and deep crustal fractures drive geothermal circulation. The water chemistry, dominated by sodium at 49 mg/L with low calcium and magnesium, points to deep circulation through silicate rock rather than limestone. Mountain Home Air Force Base, established during World War II, sits as the nearest population center.

The short walk from Hot Springs Road takes under ten minutes over uneven terrain. Water emerges hot enough to scald at the source, so test temperature carefully before entering any pools. Summer temperatures regularly exceed 100 degrees Fahrenheit in this desert. Carry water and sun protection. No facilities or shade at the spring.

Is Bat Hot Spring, Pence Hot Spring worth visiting?

Best for

  • Hot spring soaking
Bat Hot Spring, Pence Hot Spring is well suited for hot spring soaking.
Monthly Climate
32°
Jan
38°
Feb
46°
Mar
54°
Apr
63°
May
73°
Jun
83°
Jul
82°
Aug
70°
Sep
55°
Oct
42°
Nov
32°
Dec
Annual Precip: 9.6 in Annual Snow: 11.4 in
Best Time to Visit
January Air 32°F · Water 117°F · +85° contrast
December Air 32°F · Water 117°F · +85° contrast
February Air 38°F · Water 117°F · +79° contrast
January offers 51°F more contrast than July
USGS Field Measurements
Recent Temperature 114.8°F (46.0°C) Measured Mar 08, 1989
Water Chemistry Sampled 1989-03-08

The water at Bat Hot Spring, Pence Hot Spring is slightly alkaline (pH 8.2) with 243 mg/L total dissolved solids.

pH 8.2 Slightly Alkaline
pH influences mineral absorption through skin
Higher mineral concentration for therapeutic soaking
Calcium 11 mg/L
May support bone density and joint health
Magnesium 1 mg/L
Known for muscle relaxation and stress relief
Sodium 49 mg/L
Supports circulation and skin hydration
Sulfate 20 mg/L
Traditionally used for skin conditions and inflammation
Chloride 9 mg/L
Natural antiseptic with skin health benefits
Iron 50 µg/L
Iron-rich springs may support circulation
What to Bring
Swimsuit & towel
Water bottle Stay hydrated, especially in hot water
Trash bag Pack out what you pack in
Water shoes Hot ground near source
References
USGS Quad: HOT SPRING 7.5 · PP 492: 164.0 · NOAA: 2.0 · AMS Map: TWIN FALLS
Frequently Asked Questions
What is the water temperature at Bat Hot Spring, Pence Hot Spring?
Bat Hot Spring, Pence Hot Spring has a water temperature of 117°F (47°C). This is considered a hot spring, well above body temperature.
Where is Bat Hot Spring, Pence Hot Spring located?
Bat Hot Spring, Pence Hot Spring is located in Elmore County, Idaho at 2,590 feet elevation, near Mountain Home Air Force Base. Coordinates: 42.7970°N, 115.7230°W.
How do I get to Bat Hot Spring, Pence Hot Spring?
Bat Hot Spring, Pence Hot Spring has Short Walk road access, with the nearest road being Hot Springs Road (0.3 mi from the road).
What minerals are in the water at Bat Hot Spring, Pence Hot Spring?
Water chemistry analysis shows the presence of pH, Total Dissolved Solids, Calcium, Magnesium, Sodium, Sulfate, Chloride, Iron. The pH is 8.2 (slightly alkaline). Total dissolved solids measure 243 mg/L.
Is it safe to soak at Bat Hot Spring, Pence Hot Spring?
At 117°F, Bat Hot Spring, Pence Hot Spring is hot enough to require caution. Enter slowly, limit soaking sessions to 15–20 minutes, and stay hydrated. Access may be on private land or unconfirmed — verify current conditions before visiting. Always tell someone your plans before visiting remote hot springs.
Is Bat Hot Spring, Pence Hot Spring crowded?
Bat Hot Spring, Pence Hot Spring sees varying levels of visitors depending on the season and day of the week.
What should I bring to Bat Hot Spring, Pence Hot Spring?
Essentials for Bat Hot Spring, Pence Hot Spring: swimsuit, towel, water bottle, 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.
Temperature
117°F
Warm Hot Boiling
Water Temp 117°F (47°C)
Avg Air Temp 56°F
Above Ambient +61°F
Great soaking conditions March
Access
Road Access Short Walk
Nearest Road Hot Springs Road
Distance to Road 0.3 mi