Lolo Hot Springs, Granite Springs

Missoula County, Montana · Near Frenchtown
46.7280°N, 114.5330°W · 4,324 ft
111°F 4,324 ft Short Walk Camping nearby (6.3 mi)

Lolo Hot Springs, also recorded as Granite Springs, is a commercial hot springs in Missoula County, Montana, the center of a small unincorporated community on U.S. Highway 12 with a hotel and a restaurant. Frenchtown is the nearest town in the record, about twenty-five miles off. The water is hot, past soaking temperature at the source. It was strongly alkaline in the 1974 USGS sample.

Location

Lolo Creek Road is the nearest road named, under five hundred feet away. It sits fairly low for the state. Snow is serious here, ten feet in an average winter. Annual precipitation runs high. West Fork Butte Lookout, six miles away, is the nearest camping the record knows. No land owner appears in the row.

Because this is a developed commercial spring, expect a business; the record does not list a fee. December through February is what the record calls best. With that much snow, Highway 12 conditions decide everything. The USGS chemistry is half a century old, with a high pH and iron present. The source water is hotter than you would soak in.

History of Lolo Hot Springs, Granite Springs

In Salish the place is called smtt̓m̓čqi or sntt̓mčqey, which Wikipedia renders as Steam on a Ridge Top. The community that grew around the springs is the westernmost settlement on Highway 12 in Montana. The USGS sampled the water in August 1974.

Terrain

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 Lolo Hot Springs, Granite Springs.

Aerial view of the ground around Lolo Hot Springs, Granite Springs LiDAR bare-earth view of the same ground around Lolo Hot Springs, Granite Springs
Aerial LiDAR bare earth

Drag the handle to compare the two views. The orange dot marks the spring, in a frame about three quarters of a mile wide.

Setting
Hillside
The spring sits on a steep slope that climbs to the northwest.
Highest ground nearby
110 ft above the spring
Within a quarter mile, to the northwest
Cross-section through the spring

A slice through the ground from southwest to northeast, about 0.6 miles end to end.

Elevation data: USGS 3D Elevation Program. Aerial imagery: USGS The National Map. Public domain.

Heat Below
99 milliwatts per square meter of heat flow

That's about 1½ times the US average of 65. It's higher than at 46% 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.

Heat flow estimate: Stanford Thermal Earth Model (Aljubran & Horne, 2024), CC BY 4.0.

Monthly Climate
26°
Jan
26°
Feb
33°
Mar
38°
Apr
47°
May
57°
Jun
67°
Jul
67°
Aug
57°
Sep
43°
Oct
30°
Nov
23°
Dec
Annual Precip: 30.2 in Annual Snow: 121.3 in
Best Time to Visit
December Air 23°F · Water 111°F · +88° contrast
January Air 26°F · Water 111°F · +85° contrast
February Air 26°F · Water 111°F · +85° contrast
December offers 44°F more contrast than August
Current Conditions
Today 68° Low 40° Areas Of Frost then Partly Sunny 1% precip
Spring is +43° warmer
Wednesday 71° Low 43° Sunny 2% precip
Spring is +40° warmer
Thursday 76° Low 46° Sunny then Chance Light Rain 29% precip
Spring is +35° warmer
Friday 70° Low 44° Chance Light Rain then Chance Showers And Thunderstorms 50% precip
Spring is +41° warmer
Saturday 75° Low 45° Sunny 9% precip
Spring is +36° warmer
Water Chemistry Sampled 1974-08-15

The water at Lolo Hot Springs, Granite Springs is alkaline (pH 9.3).

pH 9.3 Alkaline
pH influences mineral absorption through skin
Calcium 2 mg/L
May support bone density and joint health
Magnesium 0 mg/L
Known for muscle relaxation and stress relief
Sodium 52 mg/L
Supports circulation and skin hydration
Sulfate 18 mg/L
Traditionally used for skin conditions and inflammation
Chloride 6 mg/L
Natural antiseptic with skin health benefits
Iron 30 µg/L
Iron-rich springs may support circulation
Where to Stay

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Nearby Camping
West Fork Butte Lookout 6.3 mi away

Overview West Fork Butte Lookout is an ideal place for guests to experience the mountains south of Missoula from a unique vantage point. The facility provides near-360-degree views of the surrounding area. It is equipped with basic supplies and provides guests a base camp location from which to explore the area. Access by vehicle is available for a relatively short time during the summer months and is variable during the spring and fall. From December 1 - May 1 Forest Road 37 is closed, requi...

Reservable Yes
Reserve on Recreation.gov →
Temperature
111°F
Warm Hot Boiling
Water Temp 111°F (44°C)
Avg Air Temp 43°F
Above Ambient +68°F
Great soaking conditions September
Access
Road Access Short Walk
Nearest Road Lolo Creek Road
Distance to Road 482 ft
Frequently Asked Questions
What is the water temperature at Lolo Hot Springs, Granite Springs?
Lolo Hot Springs, Granite Springs has a water temperature of 111°F (44°C). This is considered a hot spring, well above body temperature.
Where is Lolo Hot Springs, Granite Springs located?
Lolo Hot Springs, Granite Springs is located in Missoula County, Montana at 4,324 feet elevation, near Frenchtown. Coordinates: 46.7280°N, 114.5330°W.
How do I get to Lolo Hot Springs, Granite Springs?
Lolo Hot Springs, Granite Springs has Short Walk road access, with the nearest road being Lolo Creek Road (482 ft from the road).
Can I camp near Lolo Hot Springs, Granite Springs?
Yes, West Fork Butte Lookout is located nearby (6.3 miles away).
What minerals are in the water at Lolo Hot Springs, Granite Springs?
Water chemistry analysis shows the presence of pH, Calcium, Magnesium, Sodium, Sulfate, Chloride, Iron. The pH is 9.3 (alkaline).
Is it safe to soak at Lolo Hot Springs, Granite Springs?
With care. At 111°F Lolo Hot Springs, Granite Springs is hot enough to need short sessions, fifteen to twenty minutes, and plenty of water. Enter slowly and get out if you feel light-headed.
Sources: USGS NWIS, Wikipedia