There aren’t many sights more beautiful to a trout angler than the blue-green flow of the San Juan River below Navajo Dam. Packed with big browns and rainbows, this tailwater is so productive that the regulars coined a term to describe the almost elbow-to-elbow casting that sometimes occurs on popular San Juan pools such as the Texas Hole: combat fishing. But that phrase does this river a disservice. There is plenty of room to spread out. If you explore the side channels and more remote runs, the only thing around your elbows will be a hatch of midges on which rainbow trout averaging 17 inches and reaching 5 pounds or more are feeding steadily. It’s catch-and-release near the dam and one fish-minimum 20 inches-for the next 31/2 miles. But almost nobody kills a trout here, and the result is a river full of selective bruisers. Skilled anglers commonly have 20-fish days. The San Juan’s fame began years ago when a local angler came up with a pattern to match the aquatic worms in the river. The San Juan Worm, now standard in fly boxes all over the country, still works on its namesake river. But the main entr¿¿e on the trout menu is midges (mostly larvae and pupae), corresponding to tiny hook sizes 22 to 26. Fish a two-nymph rig under a strike indicator. Sweet Spot: The first 4 miles below the dam What’s Hot: Black Beauty Midge Local Advice: “The mistake I see many folks making is using too much weight on the leader when nymphing,” says John Flick of the Duranglers fly shop. Prime Time: June through mid-July, September through October More Info: Duranglers, 505-632-5952