While spending a month in Tillamook, Oregon earlier this year we did a lot of day trips. One day we stopped to visit Wahkeena Falls on our way to visit Mulmutoth Falls again. The Wahkeena Falls is also on the Columbia River and is about 13 miles East of Troutdale, Oregon.
There is a 0.2-mile hike from the parking lot at the base, which leads to the stone bridge that crosses the main part of the falls. A 0.2-mile hike from the parking lot at the base leads to the 18 foot long stone bridge that crosses the main part of the 242 foot tall falls. It is definitely worth visiting while in the area.