If you are in the area and looking for a quick whitewater fix this is a great little run easily accessible off I-5. For the put-in most use a long-ish fishermen's trail down to the river from a roadside pullout. This trail system accesses the river below Lower Kalama Falls. The first couple rapids rate class III to IV depending on flows. There is a short warmup stretch, then the river bends left and drops into the biggest rapids on the run, so far called 'First Rapid'. It is a long, steep boulder garden best scouted from the fisherman's trail on river right. Second rapid is also steep but shorter. It comes up quickly and is likewise scoutable, this time from river left. After that things taper off with a few more fun rapids until the canyon walls start to peel away. The last steep drop is called WTFalls and it is easily scouted using the rock shelf on river left. The top drop in this rapid can easily be lapped to practice boofing. Once the road comes into view on river right you are soon at the first take-out option which is Red Barn (a big red barn located near the confluence with Indian Creek). The short run that takes out here (~4 miles) is commonly called 'the Red Barn section', though drift boaters call the section downstream to Modrow bridge from it the same.
You can take-out here if you're just doing a short trip or want to run another lap. Most whitewater paddlers take out at the Red Barn. Alternatively you can continue downstream as far as Modrow Road. This section is mostly class I/II with a few riffles and headwalls near the start that soon taper off. Marietta Falls is a scenic waterfall that cascades in from river left and you get a great view from the river
The gauge on the Kalama is
located here. 500 cfs and up is best, but can be run lower. 400 cfs is still enjoyable, the min is not yet known to AW.