The waterfall featured above is Iron Creek Falls. It is located along Forest Road 25 east of Mount Saint Helens. The trail to the falls is several hundred feet long and drops right down to the creek bed, though you might have to scramble over a few downed trees to get to a good view. This time of year, when the creek flow is relatively low, you can get right out in the creek bed and shoot from directly in front of the falls. Though not particularly high (with a listed drop of 38 feet), I think this small waterfall is quite pretty with its colorful plunge pool.
Langfield Falls (below) is on Big Mosquito Creek northwest of the town of Trout Lake on Forest Road 88 just east of the Big Tire Junction. The trail to the falls is about 500 feet long, dropping to a viewpoint a short distance above the falls. As you can see from the photo below, at this time of year, when the creek flow is low, the waterfall is limited to one side of the cliff. When the creek flow is higher, the falls spread wide over the rock face, totally changing the character of these falls.