The North Fork of the South Platte River begins its journey high atop Kenosha Pass, meandering east along the scenic Highway 285 corridor as a modest mountain brook. As it travels downstream, this iconic Colorado river transforms into a premier trout fishery thanks to the influence of two major tributaries.
One of the most significant contributors is the Roberts Tunnel, a remarkable 23-mile underground diversion that channels pristine water from the bottom of Lake Dillon in Silverthorne, beneath the Continental Divide, and directly into the North Fork. This cold, clear water not only supplies drinking water to millions of Denver-area residents but also creates ideal conditions for thriving trout populations. While the Roberts Tunnel’s flow varies based on Denver’s water demands, it typically operates throughout the spring, summer, and fall, ensuring excellent fishing conditions during prime seasons.
Just downstream in the historic town of Grant, the North Fork is further enhanced by the confluence of Geneva Creek, adding additional volume and nutrients to the river. Depending on the time of year, these combined tributaries contribute between 20 and over 600+ cubic feet per second (CFS) of streamflow, creating dynamic and diverse fishing conditions.
Downstream of Grant, the North Fork of the South Platte becomes a fast-flowing, high-gradient river known for its challenging and rewarding fly fishing. Riffles and runs dominate this stretch, and slower, prime holding water for trout is carefully managed and maintained through extensive stream restoration efforts.
Many of the finest fishing stretches are located on private ranch properties, including North Fork Ranch, Shawnee Meadows, and Rawhide Fly Fishers. These ranches have invested heavily in habitat improvements, creating ideal conditions for trout to thrive despite the increased flows from the Roberts Tunnel. This combination of expertly managed water and breathtaking Rocky Mountain scenery makes the North Fork one of Colorado’s top destinations for fly fishing enthusiasts.
Downstream of Grant, the North Fork of the South Platte becomes a fast-flowing, high-gradient river known for its challenging and rewarding fly fishing. Riffles and runs dominate this stretch, and slower, prime holding water for trout is carefully managed and maintained through extensive stream restoration efforts.
Many of the finest fishing stretches are located on private ranch properties, including North Fork Ranch, Shawnee Meadows, and Rawhide Fly Fishers. These ranches have invested heavily in habitat improvements, creating ideal conditions for trout to thrive despite the increased flows from the Roberts Tunnel. This combination of expertly managed water and breathtaking Rocky Mountain scenery makes the North Fork one of Colorado’s top destinations for fly fishing enthusiasts.
This section of river offers a mix of features — from pocket water and cutbanks to deep pools and slow glides — making it suitable for dry flies, nymphing, and streamers alike. The fish here are healthy, active, and responsive to seasonal hatches. Whether you’re refining your cast or hunting for a personal best, this stretch of water provides opportunity and variety.
