Big Eightmile Creek Warm Spring

Lemhi County, Idaho · Near Salmon
44.6400°N, 113.5040°W · 7,248 ft
91°F 7,248 ft Open Short Walk US Forest Service Camping nearby (11.6 mi)

At 91 degrees Fahrenheit and 7,248 feet elevation, Big Eightmile Creek Warm Spring delivers a lukewarm soak in some of Idaho's most remote high country. Located in the Salmon National Forest of Lemhi County, it requires a short walk from Forest Road 096 through the kind of terrain most visitors only see from a distance.

Location

The spring emerges in the upper reaches of the Eightmile Creek drainage, surrounded by the steep, dry ridges of the Lemhi Range. At this elevation, the air averages just 36 degrees Fahrenheit annually, and winter dumps nearly six feet of snow. The landscape is open sagebrush and scattered conifers, with the creek cutting through rocky ground. The 91-degree water feels warmer than it sounds when ambient temperatures hover near freezing.

Access requires a roughly one-mile walk from Forest Road 096. The nearest established campground is McFarland, about 19 miles away along the Lemhi River, with nine reservable sites. Expect snow to block access from late fall through early summer. Bring everything you need, as there are no facilities at the spring itself.

History of Big Eightmile Creek Warm Spring

The spring sits along one of many thermal corridors that thread through eastern Idaho's Basin and Range geology. Faults running parallel to the Lemhi Range allow groundwater to circulate deep enough to pick up modest heat before surfacing. The area around Salmon has been used by Shoshone-Bannock people for centuries, and early trappers and miners noted these warm seeps while working the surrounding drainages.

Monthly Climate
15°
Jan
17°
Feb
25°
Mar
31°
Apr
42°
May
53°
Jun
63°
Jul
62°
Aug
52°
Sep
37°
Oct
23°
Nov
13°
Dec
Annual Precip: 18.2 in Annual Snow: 71.7 in
Best Time to Visit
December Air 13°F · Water 91°F · +78° contrast
January Air 15°F · Water 91°F · +76° contrast
February Air 17°F · Water 91°F · +75° contrast
December offers 50°F more contrast than July
Current Conditions
41°F
NE 3.6 mph 42% Good soaking weather
Saturday 62° Low 38° Sunny 1% precip
Spring is +29° warmer
Sunday 74° Low 40° Mostly Sunny
Spring is +17° warmer
Monday 76° Low 47° Sunny
Spring is +15° warmer
Tuesday 79° Low 46° Sunny 1% precip
Spring is +12° warmer
Wednesday 76° Low 52° Mostly Sunny 9% precip
Spring is +15° warmer
Where to Stay

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Nearby Camping
Mc Farland Campground 11.6 mi away

Overview McFarland Campground offer 9 campsites for both RVs and tent camping along the Lemhi River. The Lemhi Valley lies between the Beaverhead Mountains and the Lemhi Range, where the river creates a riparian zone in an otherwise arid region.  Recreation McFarland Campground offers many recreation opportunities including public river access for fishing the Lemhi River, and area roads lead into the Beaverhead and Lemhi Ranges. The surrounding area offers a multitude of recreation opportunit...

Reservable Yes
Reserve on Recreation.gov →
Mile-High Advisory 7,248 ft

Big Eightmile Creek Warm Spring sits at 7,248 feet above sea level, way above the mile-high mark. You may not feel the altitude strongly, but hot water still dehydrates you faster at elevation. UV is about 29% stronger than at sea level, so bring sunscreen and drink more water than you normally would.

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Temperature
91°F
Warm Hot Boiling
Water Temp 91°F (33°C)
Avg Air Temp 36°F
Above Ambient +55°F
Good soaking conditions May
Access
Open
Road Access Short Walk
Nearest Road National Forest Development Road 096
Distance to Road 0.9 mi
Land
Ownership Federal
Agency US Forest Service
Designation National Forest
Unit Salmon National Forest
Manager US Forest Service
Protection 3 - Protected, subject to extractive use
Frequently Asked Questions
What is the water temperature at Big Eightmile Creek Warm Spring?
Big Eightmile Creek Warm Spring has a water temperature of 91°F (33°C). This is a warm thermal spring.
Where is Big Eightmile Creek Warm Spring located?
Big Eightmile Creek Warm Spring is located in Lemhi County, Idaho at 7,248 feet elevation, near Salmon. Coordinates: 44.6400°N, 113.5040°W.
How do I get to Big Eightmile Creek Warm Spring?
Big Eightmile Creek Warm Spring has Short Walk road access, with the nearest road being National Forest Development Road 096 (0.9 mi from the road).
Is Big Eightmile Creek Warm Spring free to visit?
Big Eightmile Creek Warm Spring has Open access. It is managed by US Forest Service.
Can I camp near Big Eightmile Creek Warm Spring?
Yes, Mc Farland Campground is located nearby (11.6 miles away).
Is it safe to soak at Big Eightmile Creek Warm Spring?
Big Eightmile Creek Warm Spring is generally safe for soaking at its recorded temperature. Always tell someone your plans before visiting remote hot springs.
Is Big Eightmile Creek Warm Spring crowded?
Big Eightmile Creek Warm Spring sees varying levels of visitors depending on the season and day of the week.
What should I bring to Big Eightmile Creek Warm Spring?
Essentials for Big Eightmile Creek Warm Spring: swimsuit, towel, water bottle, warm layers for before and after soaking, camping gear, a trash bag to pack out what you pack in.