Keith, St. Louis ponds are located near Gervais, about 11 miles north of Keizer. You can get to it from Salem by just going north out river road, and when River splits and you have to take a left to stay on River itself, you continue on your path and the road will turn in to French Prairie road. About a half mile later, take a right on to St. Louis road. Take a right on Tesch road, which is immediately after the RR track crossing. This time of year there is a gate on the road and you can't drive in to the main parking areas, but you can walk in. Coming from Hwy 99, just take St. Louis road to the west out of Gervais. It's the only road in Gervais that crosses over I-5, and you would take a left on to Tesch road immediately before the tracks.
St. Louis is primarily managed for warmwater fisheries, and the ponds grow monster channel cats. I have personally seen a 22 pounder, and someone caught a 39 pounder a while back. The bass fishing is fair, but they can be hard to catch because of the high amount of angling pressure on them, and there is also a lot of catch-and-take pressure on the bass as well. Crappie fishing is pretty good if you put in the time and find the good spots (or I could tell you... lol). The bluegill are thick and are extremely easy to catch if you want to take kids out and catch lots of fish in the summer time. By the way, only ponds 3 and 6 are stocked with trout (including the brooders).
Google Earth coordinates:
45 06'46.57" N 122 55'54.10" W - Main parking lot
45 06'44.20" N 122 55'45.34" W - Pond 6
45 06'49.12" N 122 55'57.43" W - Pond 3