Fly Fishing South Boulder Creek - Below Gross

Overview

South Boulder Creek below Gross Reservoir flows through a rocky canyon of pools, riffles and pocket runs. Reservoir releases influence its depth and current, with brown and rainbow trout in the drainage. Clear-water seams and steep canyon banks give this small tailwater a distinctive, close-range fishing character.

Flies for the Canyon Water

Small mayfly and midge nymphs offer choices for deeper seams. Set weight and leader length for the chosen pocket, using a controlled drift to keep the fly in its slower holding water. A dry-dropper provides another way to cover a riffle edge and the current below it.

Blue-winged olive, caddis, stonefly, pale morning dun and Yellow Sally imitations broaden the fly box. Choose among them from visible insects and the fish’s feeding behavior. Hoppers, ants and beetles offer terrestrial options along vegetated banks during warmer weather.

The creek’s compact channel rewards short, accurate casts and patient line control. Read each run before choosing a position; releases can alter both its depth and the seams available beside shore. The canyon walls, rock structure and quieter pockets provide the interest of working this tailwater.

Access

Park at Walker Ranch Loop Trailhead off Flagstaff Road and follow the loop trail downhill toward South Boulder Creek. The county map marks fishing locations at the creek; use those trail approaches and remain within the recreation area. See the county’s trailhead and fishing information and marked trail map.