I can help give you directions to Blue Creek, Barrier Dam and Misson Bar on the Cow.
You'll take I-5 North to Hwy 12 east. Turn Right on Hwy 12 and head east 6.5 miles to Ethel.
In Ethel turn right on Tucker rd, You'll see Big brown sign.
(Cowlitz river trout hatchery, Blue creek boat launch)
Heading south on Tucker rd. for about a mile it curves off to the right, go straight on Classe rd. Keep following the brown signs. Take Classe Rd. a couple miles to the stop sign and a tee in the road. This is Spencer Rd.
Spencer rd. can get you to all 3 access areas.
If you go right on Spencer Rd. about 6 miles you'll come to Buckley rd. to the right, this will take you to the Mission Bar launch, with bank access above and below the launch.
From the Classe rd. stop sign, you can go left on Spencer Rd.(keep following the brown signs)after a mile you'll see the sign for the Blue creek launch and drive way to the hatchery and launch to the right. Hollow the Drive wayto the boat launch parking lot and pull all the way to the back, under the tall trees to the right and the trail head to Blue Creek bank access. It's about a mile hike in on a sometimes very muddy trail, expect lot's of people, but fishing can be hot.
Keep going east on Spencer rd. past the Blue Creek driveway about 7 more miles (keep following brown signs "Barrier Dam launch") and you'll come to the Barrier Dam launch and lot's of bank access from the dead line below the dam to Mill creek below the launch.
Hope this is some help.