The Monster section of the South Santiam is an interesting and scenic class IV stretch that flows through a roadside gorge in the Willamette National Forest. The South Santiam riverbed is one of the oldest geologically in the Cascades, so there are a few unseen hazards boaters should be aware of. In several spots (especially around the Monster and Tomco Falls) there are large potholes, undercuts, and other dangerous underwater rock formations. You don't even want to think about swimming once you enter the gorge! We usually put in on about a mile above the US 20 bridge so we can run class III Longbow Falls as a warm up.
Mike Haley crashes through Longbow Falls at 1700 cfs.
Once you pass under the US 20 bridge the pace picks up and there are many fun rapids, all of which are pretty easy to boat scout. The only spot that currently contains dangerous wood is a ledge about 5 drops down from the bridge. Here a log extends from the right bank into the foam beneath the ledge. This drop has a nice pool above it so you can spot the log from your boat and run left pretty easily.
Pete Giordano in the first part of the gorge on a very cold, icy day.
Paddlers must stay alert as they approach the monster, a sliding twenty foot falls that would be a really nice drop if it weren't for the undercut filled runout. There is a small ledge about 100 feet upstream of the monster, so once you run this drop immediately eddy out to portage this class six drop.
Pete runs the ledge above the Monster. Brrr.. this was a very cold trip!
(Note the road at the top of the photo. It is possible to scout this drop
beforehand, or hike out at any point during the run..)
Pete contemplates the Monster on a very cold, icy day. Below the first
drop pictured here is a
long slide that slams into the wall underneath where Pete is standing. The river then makes a sharp left and slams into another severely undercut wall. This drop has been run by a few Corvallis boaters, but it is not recommended.
Nope, still really scary... The author contemplates the hideous undercuts
on the Monster after a run down nearby Canyon Creek. The small ledge
leading into this drop is
Just downstream of the monster is Crawdad, a twisty drop with a violent eddy against the wall river left. This drop looks relatively easy but in the words of the guidebook it has "munched lots of boaters." Case in point: A friend of ours got caught in the violent eddy up against the river left wall, flipped and was forcefully wedged between the walls of the outlet slot. He swam and was flushed very, very deep (he said he opened his eyes and everything was dark) He was underwater for a total of about twenty seconds, then he popped up in the pool about sixty feet downriver.
If you decide not to run Crawdad, a fun way to cut the portage short is to toss your boat in and jump after it below the Crawdad- above 2000 cfs this becomes less of an option because the current picks up, but below that the river is mellow all the way around the corner, making for a fun swim between the rock walls even in the dead of winter!
Pete gets ready to leap in after his boat below Crawdad.
The last major drop is Tomco Falls, which is really more of a chute than a true waterfall. This rapid is often run but beware- the underlying rock contains huge potholes, undercuts, and a really nasty crack that much of the water pours into. This one is safer with more water in my opinion, though many good boaters end up running it upside down! Portage on the left or run one of the right slots if you don't like the main chute.
Pete with Tomco in the background at a low flow of 700 cfs- note the potholes!
Below Tomco is the most picturesque part of the gorge, with small rapids but nice scenery. The gorge gets very narrow in a few places, but the rapids are small so wood is not really much of a concern for alert boaters.
Just above the take out at Cascadia is an excellent side surfing hole which gets very sticky at some flows- you can end your trip with a great surf or a quick swim depending on how your day is going...