Boise, S. Fork
2. Danskin Bridge to Neal Bridge (near Arrowrock Reservoir)(Canyon Run)
| Difficulty | III-IV |
| Length | 16 mi |
| Avg Gradient | n/a |
| Gauge | Sf Boise River at Anderson Ranch Dam Id |
| Flow Rate as of 1 hour | 1610 cfsrunnable |
| Reach Info Last Updated | April 25, 2023 |
River Description
This is a long, challenging run that cuts through a deep, roadless canyon. There is no cell phone coverage, and given the sheer rhyolite cliffs, evacuation on foot to the canyon rim is often impossible. Therefore, anyone attempting this section should be highly skilled and likewise fully prepared for any and all contingencies.
The first five miles downstream from Danskin bridge are characterized by swift-moving water through majestic landscapes punctuated by two pastoral ranches, which are located on river-left.
Beyond the second ranch, look for a conical rock formation high on the river-left ridge. This is the Witch's Hat, and it roughly marks the entrance to the canyon proper.
The section that follows is a series of Class II and III, read and run rapids that require some basic moves between holes, rocks, and strainers. The exceptions to this are Raspberry (Class III), Buffalo Creek (Class IV), and Fiddler (Class III). Each of the aforementioned rapids have the possibility of dangerous strainers and/or pin hazards. Scouting is recommended and achievable for all via trails located on river-left.
Be advised: a swim on any of these rapids is potentially deadly – they are long, shallow, and have known pin hazards. Likewise, with Anderson Ranch Dam being bottom-released, the water in the canyon stays very cold throughout the summer months.
The shuttle through Prairie is approximately one hour. Local shuttle service is available.
River Features
Put In
Put in has large parking area and vault toilets.
Raspberry
Raspberry (first of three named rapids) is a fairly straight forward Class III. Easily scoutable from pool on river left.
Enter center then move left (at 1200CFS)
Wood is always a possible hazard, be aware.
Buffalo Creek
Buffalo Creek (second of three named rapids) is a Class IV due to the length of the rapid. A failed roll at the entrance would result in a long and rocky swim with possible pin hazards.
Enter center/left, catch the eddy on river left after the first couple of moderate hits, then continue down the left side, picking your way between holes and rocks (1200 CFS).
Easily scoutable from pool on river left. Also a good place for lunch.
Always look for wood on this section.
Fiddler (aka b***ches brew)
Straight forward Class III (third of three named rapids).
Enter far right move to center.
Easily scoutable from pool on river left.
Wood is always a risk on this section.
Take Out
Take out on river left just before Neal Bridge on Black's Creek Road.
Trip Reports
Log in to add a reportKudos to the previous report of the log on Raspberry. I would almost describe the tenuous pin of the log as 'shaky shaky.' Thanks to their report, we also lined the boat down the first quarter of the rapid and over the wood. The water was fierce, but my boat-mate was a haus, and he held onto my 16-footer as it swung down the steep first drop. Great call, solid trip, better crew.
Strainer blocking river-left/center entry to Raspberry. Be sure to scout. You can line a boat over the top of the strainer at 1600 cfs, may be difficult at lower water.
No wood hazards on July 10, 2021 at 1200 CFS.
River wide log jam approx 2 miles above Neal bridge. Unrunnable with poor options for portage. Extreme danger at this time.
river wide log jam taken out July 06. only far left channel opened, still use caution. pink ribbon on river left indicates approach
Have done this run at 4700. Very nice run. Starts as flat water, then picks up and soon becomes continuous wave train. Isolated and water moves fast. The stand-out rapid is Devil's Hole; look for a creek on the left exiting a rocky amphitheater followed by tree covered bar on left. Easy scout on left.
DANGER: RIVER-WIDE LOG JAM 3/4 mile below Smith Creek, close to the take out. You should definitely scout this one BEFORE putting on the river. The scout is easily done by walking to cliff edge where the road closely approaches the canyon on the way to Neal Bridge. It is 3/4 mile after you see Smith Creek entering the canyon. The portage is class V and only possible on the left. Do not take this one lightly.
Riverwide strainer. Mandatory portage, very difficult - on river left. Scout from canyon rim before launch.