The Pumphouse section of the Upper Colorado River is a renowned destination for fly fishing enthusiasts within a 2 hour drive of the Denver metropolitan area. Pumphouse offers over three miles of easily accessible wade fishing opportunities. This beautiful, remote stretch of river is home to rainbow trout, brown trout, Colorado whitefish, and the occasional cut-bow. With its long riffles, braided sections that allow for easy crossing, and deeper holes that may be holding the fish of a lifetime, Pumphouse provides a diverse and rewarding fishing experience.

As professional guides at Fish On Colorado, we’ve spent countless hours navigating these waters and have compiled our top five tips to enhance your fly fishing adventure in this remarkable area.

Understand the River’s Layout and Access Points

The Pumphouse section offers over three miles of easily accessible wade fishing. Familiarize yourself with the river’s layout, including its long riffles, braided sections, and deeper holes. These features not only provide diverse fishing opportunities but also allow for easy crossing and targeting specific sections of water. Additionally, for the more adventurous angler, hiking upstream into Gore Canyon can provide an incredible fishing experience in a more secluded setting. The canyon’s steep walls and rugged terrain make for a stunning backdrop, but be prepared for a more challenging hike and wade experience.

The upper Colorado is really a tailwater that acts as a freestone. There are over 6 different reservoirs the water has flowed through to get to this point with dozens of tributaries adding to the flow. The river clarity doesn’t need to be as good as one typically thinks. 2ft of visibility is all you need to have a successful day on the water. This means leave your 7x at home and tie on some 4x or 5x.

Select the Right Equipment and Flies

Equipping yourself with the appropriate gear is crucial for a successful outing. A 9-foot, 5-weight rod is versatile for this section, handling various fly sizes and the occasional larger fish. Streamer fishing can be very productive in this stretch so you may want to bring along a 7 or 7wt to cast those heavier bugs.

Given the diverse aquatic life, it’s wise to carry a selection of nymphs, dry flies, and streamers. Patterns such as Pheasant Tail Nymphs, Elk Hair Caddis, and Woolly Buggers often yield good results and don’t forget the worm and egg in the early Spring and late Fall. Adjust your fly choice based on the season and observed insect activity.

Master Seasonal Strategies and Best Times to Fish

The Pumphouse section’s fishing conditions vary with the seasons:

  • Spring (March-May): Ice-off typically occurs in late February to early March. As runoff begins, flows increase, making fishing more challenging. However, early spring offers excellent pre-runoff fishing with streamers and nymphs. The fish are hungry coming out of winter and the Rainbow spawn is happening.
  • Summer (June-August): This is the prime time for Hopper Dropper rigs, with prolific insect hatches including caddis, PMDs, and stoneflies. Flows begin to stabilize post-runoff, providing excellent conditions for wading and floating.
  • Fall (September-November): Arguably the best time of year to fish, with lower, clear water and aggressive brown trout preparing to spawn. Smaller nymphs and streamers are particularly effective.
  • Winter (December-February): While parts of the river remain fishable, heavy ice buildup can make access difficult. The Pumphouse section can freeze over during prolonged cold spells, but on milder winter days, midges and small nymphs can still be effective in slower water.

Safe Flows for Wading

Understanding river flows is crucial for safe wading along this stretch:

  • Ideal Wading Flows: 500-800 CFS (Cubic Feet per Second)
  • Challenging but Doable: 800-1,200 CFS
  • Not Recommended for Wading: Over 1,200 CFS

During peak runoff (May-June), flows can exceed 4,000 CFS, making wading extremely dangerous. Always check USGS flow gauges before heading out.

Float Fishing the Pumphouse Section

For those looking to cover more water and access hard-to-reach fishing spots, float fishing is an excellent option. The Pumphouse to Radium stretch is one of the most popular float trips on the Upper Colorado River, offering a mix of slow-moving water, riffles, and moderate rapids.

  • Best Flows for Floating: 800-3,500 CFS provides ideal conditions for rafts and drift boats. Below 800 CFS, navigating becomes a little more difficult due to exposed rocks and shallow areas.
  • Recommended Gear: A drift boat or raft rigged with a fishing frame allows for a productive day on the water. Bring a variety of fly patterns to adjust to changing conditions.
  • Fishing Techniques: Float fishing allows for extended drifts with nymph rigs and streamers. Dry-dropper setups are also effective along banks and seams.
  • Safety Considerations: Be aware of changing flows and rapids, particularly Eye Of The Needle and Yarmony rapids both of which can be tricky at higher flows. Always wear a life jacket and check flow conditions before launching.

Pumphouse is a very popular recreational area and preserving the pristine nature of the Pumphouse section is essential for future generations of anglers. Practice catch and release to maintain healthy fish populations. Be aware of and adhere to local fishing regulations, including any seasonal restrictions or gear limitations. Additionally, be mindful of the diverse wildlife that calls this area home, including mule deer, elk bears, bald eagles, and bighorn sheep. Respecting the environment ensures a sustainable and enjoyable experience for all.

Hopefully these expert tips, will help you be prepared to enjoy a successful and fulfilling fly fishing adventure in the Pumphouse section of the Upper Colorado River. Whether you’re a novice or an experienced angler, the combination of strategic preparation and respect for the natural environment will enhance your experience in this remarkable setting.