SpongeBob.
I am an officer here at Fort Lewis. The Range Control area access number is 253-967-6277. You can get a vehicle access pass for the Nisqually. The areas you will be parking in are Training Areas 16 & 18 for the upper river (Tank Bridge Crossing) and Training Area 3 if you plan to fish the Mounts Road Bridge Area. Access through the Dupont & Main Gate is a little more problematic. The Range Pass is SUPPOSED to give you access through the gate, however, the soldiers at the gate are spring loaded to deny any vehicle / person that either does not have a Military ID or does not have an escort with an ID. Unfortunately, since the soldiers at the gate frequently rotate the tasking, they are not updated on the range pass (and hunting pass) policy. The success rates of my civilian buddies (who I don't have time to escort) is about 50% getting through the gates. The Main Gate is usually your best bet, because their is more long term MP leadership there who understanding the pass proceudres. The soldiers at the Dupont Gate are usually Combat Arms soldiers who are just tasked for the mission of guarding the walls. However, Once you get a Range Pass from Range Control, you can access the Nisqually without having to go through a gate if you enter the Reservation from the East Gate road. Go south on Hwy 507 from the Roy Y and turn right onto East Gate Road. Head West for about 6 miles and turn left at the C-5 Mock-up (Can't miss it). Follow that hardball until you hit the Nasty and the Tank Bridge. Get a Training Area Map from Range Control and you should not have any problems. And yes, the chums are in....but the river is...well...Nasty right now