Weir Creek Hot Springs

Also known as: Weir hotsprings
Mineral County County, Idaho · Near Superior
46.4640°N, 115.0350°W · 2,885 ft
117°F 2,885 ft Open Short Walk US Forest Service Camping nearby (9.0 mi)
Weir Creek Hot Springs
File:M 4611540 ne 11 060 20210924.tif — public domain

Weir Creek Hot Springs surfaces at 117°F with strongly alkaline water (pH 9.4) in Idaho's Clearwater National Forest. Located at 2,885 feet on federal land, the spring requires a short walk of about 636 meters from the nearest road. Sodium-dominant chemistry with minimal calcium and magnesium points to deep volcanic circulation through granitic bedrock.

The spring sits in the densely forested mountains of northern Idaho's Clearwater drainage, where annual precipitation exceeds 48 inches and snowfall averages over 209 inches. Thick stands of western red cedar, Douglas fir, and grand fir blanket the surrounding slopes at this elevation. The terrain is steep and creek-cut, with Weir Creek carving through the narrow canyon below. Superior, the nearest town, lies across the Mineral County landscape to the west.

History of Weir Creek Hot Springs

The spring takes its name from Weir Creek, along which it emerges. Castle Butte Lookout, a fire lookout cabin first built in 1916 and rebuilt in 1950, stands about 14.5 kilometers away at 6,659 feet, reflecting the long US Forest Service presence in the area. The spring remains undeveloped and publicly accessible on National Forest land, drawing soakers who build informal rock pools along the creek.

Heavy snowfall buries this area from November through April, making summer and early fall the practical soaking season. The 636-meter trail from the road can be slippery and steep. Bring water shoes for creek crossings. No facilities exist on site. Castle Butte Lookout is reservable for overnight stays and provides a high-elevation base camp for exploring the region.

Is Weir Creek Hot Springs worth visiting?

Best for

  • Hot spring soaking
  • Overnight camping trips
Weir Creek Hot Springs is well suited for hot spring soaking and overnight camping trips.
Monthly Climate
29°
Jan
30°
Feb
37°
Mar
42°
Apr
51°
May
60°
Jun
71°
Jul
71°
Aug
61°
Sep
47°
Oct
34°
Nov
27°
Dec
Annual Precip: 48.8 in Annual Snow: 209.1 in
Best Time to Visit
December Air 27°F · Water 117°F · +90° contrast
January Air 29°F · Water 117°F · +88° contrast
February Air 30°F · Water 117°F · +87° contrast
December offers 44°F more contrast than August
USGS Field Measurements
Recent Temperature 116.6°F (47.0°C) Measured Jul 14, 1982
Water Chemistry Sampled 1982-07-14

The water at Weir Creek Hot Springs is alkaline (pH 9.4).

pH 9.4 Alkaline
pH influences mineral absorption through skin
Calcium 3 mg/L
May support bone density and joint health
Magnesium 0 mg/L
Known for muscle relaxation and stress relief
Sodium 28 mg/L
Supports circulation and skin hydration
Sulfate 18 mg/L
Traditionally used for skin conditions and inflammation
Chloride 2 mg/L
Natural antiseptic with skin health benefits
Nearby Camping
Castle Butte Lookout 9.0 mi away

Overview Castle Butte Lookout is a unique cabin perched on a rocky point, 6,659 feet above sea level. It offers breathtaking, 360-degree views of the Selway-Bitterroot Wilderness, the Seven Devils Mountains, the Great Burn area and the deep canyons of the North Fork Clearwater River's upper drainages. A cabin was first constructed on this site in 1916 and was replaced in 1928 with a log cabin featuring a cupola. The current lookout was built in 1950. Access to the lookout is via the Lolo M...

Reservable Yes
Reserve on Recreation.gov →
What to Bring
Swimsuit & towel
Water bottle Stay hydrated, especially in hot water
Camping gear Nearby camping at Castle Butte Lookout
Trash bag Pack out what you pack in
Water shoes Hot ground near source
References
USGS Quad: GREYSTONE BUTTE 7.5 · PP 492: 1.0 · NOAA: 1.0 · AMS Map: HAMILTON
Frequently Asked Questions
What is the water temperature at Weir Creek Hot Springs?
Weir Creek Hot Springs has a water temperature of 117°F (47°C). This is considered a hot spring, well above body temperature.
Where is Weir Creek Hot Springs located?
Weir Creek Hot Springs is located in Mineral County, Idaho at 2,885 feet elevation, near Superior. Coordinates: 46.4640°N, 115.0350°W.
How do I get to Weir Creek Hot Springs?
Weir Creek Hot Springs has Short Walk road access (0.4 mi from the road).
Is Weir Creek Hot Springs free to visit?
Weir Creek Hot Springs has Open access. It is managed by US Forest Service.
Can I camp near Weir Creek Hot Springs?
Yes, Castle Butte Lookout is located nearby (9.0 miles away).
What minerals are in the water at Weir Creek Hot Springs?
Water chemistry analysis shows the presence of pH, Calcium, Magnesium, Sodium, Sulfate, Chloride. The pH is 9.4 (alkaline).
Is it safe to soak at Weir Creek Hot Springs?
At 117°F, Weir Creek Hot Springs is hot enough to require caution. Enter slowly, limit soaking sessions to 15–20 minutes, and stay hydrated. Always tell someone your plans before visiting remote hot springs.
Is Weir Creek Hot Springs crowded?
Weir Creek Hot Springs sees varying levels of visitors depending on the season and day of the week.
What should I bring to Weir Creek Hot Springs?
Essentials for Weir Creek Hot Springs: swimsuit, towel, water bottle, camping gear, 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 47°F
Above Ambient +70°F
Perfect soaking weather March
Access
Open
Road Access Short Walk
Distance to Road 0.4 mi
Land
Ownership Federal
Agency US Forest Service
Designation National Forest
Unit Clearwater National Forest
Manager US Forest Service
Protection 3 - Protected, subject to extractive use