Opal Lake is one of the many small lakes that dot the Willamette National Forest.
Get a good Forest Service map to locate FR 2207 and get your bearings. The hike itself is short from the road down a rocky trail that is steep, but just a half mile to the lake itself.
When we were there it was August and the mosquitoes were in fine fettle. You have been warned. The lake is in a bowl and air movement is minimal.
You can camp, but will need to pack EVERYTHING in and out. There is no water other than the lake and the site is primitive. Filter or treat any water you take from the lake.
The lake is small, but allegedly stocked with fish, should you wish to catch your dinner.
The access to the trail and lake are sufficiently obscure and difficult that usage is very light. If you want a primitive weekend without neighbors, Opal Lake is a good choice.
Permits & Passes: Park at a wide spot at the edge of FR 3372. You're supposed to have a Wilderness Self-issue permit, but a Northwest Forest pass isn't requried.
Distance: The hike from the road to Opal Lake is short ... about a half mile. The trail runs from one end of the lake to the other but doesn't loop. You might want to bushwhack to the source of Opal Creek if you're feeling perky. This is not a kid-friendly hike.
Elevation gain: 400 ft.
Level of difficulty: Moderate. Because it's so short, it could be considered an easy hike.
Season: Late spring through fall.
From I-5 near Salem, drive east on Hwy 22 about 49.5 miles, then turn left on to French Creek Road (FS 2223); continue about five miles. When you run into gravel road, you will be on Forest Service road (FSR) 2209. Turn right on road 2207 and continue 9 miles to the Opal Lake trail head on the right. The trailhead is not distinctively marked so you'll need to pay attention or you'll drive by it.
For accurate, up-to-date information, visit the ranger station at Detroit Lake for Forest Service maps.