At 142°F, the source water at Sheep Creek Bridge Hot Spring is hot enough to cause burns. Some hot springs this hot have cooler side pools or downstream areas suitable for soaking — always test the water temperature before entering.
File:-IDAHO-B-0087- North Fork of Boise River - Twin Springs (5644825825).jpg — cc by-sa 2.0
Sheep Creek Bridge Hot Spring surfaces at 142 degrees Fahrenheit alongside Middle Fork Road in Boise County, making it one of the hotter roadside springs in the Boise National Forest. USGS analysis shows a pH of 9.5 with zero magnesium — unusually pure alkaline water that reflects deep geothermal circulation through granitic rock.
The spring emerges just 278 feet from Middle Fork Road at 3,540 feet elevation, where the Middle Fork Boise River cuts a forested canyon through central Idaho. Ponderosa pine and Douglas fir line the slopes above the road. Steam rises from the source in cooler months, and mineral residue marks the rocks near the outflow. The river runs nearby, providing a cold-water contrast during warmer seasons.
History of Sheep Creek Bridge Hot Spring
The spring taps into the same deep geothermal system that feeds numerous thermal features along the Middle Fork Boise River corridor. Its strongly alkaline chemistry — very low calcium, no magnesium, moderate sodium — indicates water that has circulated through the Idaho Batholith for potentially thousands of years before surfacing here. The area saw mining activity in the nineteenth century around nearby Idaho City.
Water at the source is dangerously hot at 142 degrees. Look for spots where it mixes with cooler creek water. The road can be rough and seasonal — check conditions before driving. Ninemeyer Campground is about 10 km away but has limited amenities due to past wildfire damage. Best visited mid-May through late September.
Is Sheep Creek Bridge Hot Spring worth visiting?
Best for
Observing powerful hot springs
Easy day trips
Overnight camping trips
Not ideal for
Casual soaking
Sheep Creek Bridge Hot Spring is well suited for observing powerful hot springs and easy day trips.
Monthly Climate
29°Jan
32°Feb
39°Mar
45°Apr
55°May
65°Jun
76°Jul
75°Aug
65°Sep
50°Oct
38°Nov
28°Dec
Annual Precip: 26.6 inAnnual Snow: 85.5 in
Best Time to Visit
DecemberAir 28°F · Water 142°F · +114° contrast
JanuaryAir 29°F · Water 142°F · +113° contrast
FebruaryAir 32°F · Water 142°F · +110° contrast
December offers 48°F more contrast than July
USGS Field Measurements
Recent Temperature
141.8°F
(61.0°C)Measured May 27, 1981
Water ChemistrySampled 1981-05-27
The water at Sheep Creek Bridge Hot Spring is alkaline (pH 9.5).
Overview:Due to a wildfire, there are no amenities at the campground. Currently there are no developed campfire rings therefore when Stage 1 fire restrictions area in effect, no fires are permitted.A stay at Ninemeyer Campground enables guests to enjoy all the beauty and recreation offered along the (Middle Fork Boise River Road) Forest Service (FS) Road 268. Weather is usually good from mid-May through late September and is easily accessible by car in good weather, although the road is some...
What is the water temperature at Sheep Creek Bridge Hot Spring?
Sheep Creek Bridge Hot Spring has a water temperature of 142°F (61°C). This is considered a hot spring, well above body temperature.
Where is Sheep Creek Bridge Hot Spring located?
Sheep Creek Bridge Hot Spring is located in Boise County, Idaho at 3,540 feet elevation, near Idaho City. Coordinates: 43.6960°N, 115.6580°W.
How do I get to Sheep Creek Bridge Hot Spring?
Sheep Creek Bridge Hot Spring has Roadside road access, with the nearest road being Middle Fork Road (278 ft from the road).
Is Sheep Creek Bridge Hot Spring free to visit?
Sheep Creek Bridge Hot Spring has Open access. It is managed by US Forest Service.
Can I camp near Sheep Creek Bridge Hot Spring?
Yes, Ninemeyer Campground is located nearby (6.1 miles away).
What minerals are in the water at Sheep Creek Bridge Hot Spring?
Water chemistry analysis shows the presence of pH, Calcium, Magnesium, Sodium, Sulfate, Chloride. The pH is 9.5 (alkaline).
Is it safe to soak at Sheep Creek Bridge Hot Spring?
The water at Sheep Creek Bridge Hot Spring reaches 142°F, which can cause severe burns. Do not enter the source pool directly — look for cooled side pools or downstream areas where the water has cooled to a safe temperature. Always tell someone your plans before visiting remote hot springs.
Is Sheep Creek Bridge Hot Spring crowded?
Sheep Creek Bridge Hot Spring is accessible from a paved road, making it easy to reach. Weekends and holidays may be busier — consider visiting on a weekday for a quieter experience.
What should I bring to Sheep Creek Bridge Hot Spring?
Essentials for Sheep Creek Bridge Hot Spring: 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
142°F
WarmHotBoiling
Water Temp142°F (61°C)
Avg Air Temp50°F
Above Ambient+92°F
Perfect soaking weatherMarch
Access
Open
Road AccessRoadside
Nearest RoadMiddle Fork Road
Distance to Road278 ft
Land
OwnershipFederal
AgencyUS Forest Service
DesignationNational Forest
UnitBoise National Forest
ManagerUS Forest Service
Protection3 - Protected, subject to extractive use
