North Fork South Platte River

The North Fork is the small, brushy water most Front Range anglers drive past on the way to Cheesman or Deckers, and that's the appeal. It runs about 30 miles roughly west to east down US-285 from near Grant through Bailey, Pine Junction, and Buffalo Creek before joining the mainstem South Platte at the town of South Platte. What makes it fish more like a tailwater than its size suggests is the Roberts Tunnel: Denver Water's 23-mile trans-basin diversion from Dillon Reservoir surfaces into the river near Grant, and when it's running it props flows up and evens out the freestone's natural swings. The fish are mostly wild browns and rainbows with cutbows mixed in, running smaller than the tailwater trout downstream — a good day is 10- to 14-inch fish with the occasional better one, plus genuinely large trout on the private leases.

This is tight, technical, wade-only water: shallow riffles, quick seams, and pocket water broken up by occasional deep holes and undercut banks. The gin-clear flows and heavy streamside brush reward short-line nymphing over long drifts. Standard sight-nymphing works day to day, and 6X tippet on the dropper is normal with size 22-24 midges in winter. Midges carry the cold months, Baetis bracket spring and fall, caddis and stoneflies fill summer, and morning Tricos are a July-August staple. Feeding windows are more forgiving than on Cheesman, and midday is prime once the canyon warms and light reaches the water. Best flows run roughly 150-250 CFS, with 200 close to ideal; it gets pushy and off-color during spring runoff from late May into June, and skinny by late summer if the tunnel throttles back.

The catch is access. A lot of the best water — the three-mile Boxwood Gulch / Long Meadow stretch between Bailey and Grant, and Blue Quill's Shawnee Meadows and Rawhide leases — is private trophy water you pay to fish. Public water is limited but real: Pine Valley Ranch Park (Jefferson County Open Space) south of Pine Junction is the reliable free stretch, with more scattered public access toward the confluence. It's an hour from Denver, lightly pressured compared to the marquee South Platte canyons, and a solid cold-weather option when you want moving water without a crowd. The mining legacy upstream means bug life and fish size lag the mainstem — an honest trade-off for the quiet.