Big Thompson River – 10/10/2023

Time: 11:30AM – 3:30PM

Location: Canyon below Lake Estes

Big Thompson River 10/10/2023 Photo Album

Last week on a trip with Amy and Jane to a relatively remote area in Colorado, I relapsed into my gastrointestinal illness. I was in a difficult situation, as there was only a couple outdoor hotspots, where I was able to obtain cell phone reception, and the closest pharmacy was thirty miles away. Fortunately I was able to connect with the office of my primary care physician, and we used scheduled call back times to generate a prescription at the closest town. Jane and Amy made the 1.5 hour roundtrip on Thursday, October 5, and this enabled me to initiate my dosage that same day. Although I missed two days of highly anticipated hiking with my wife and daughter, the medicine kicked in and alleviated my concern over the four hour return drive on Saturday.

By Monday I was feeling close to normal, and with another very fine autumn day forecast for Tuesday, I made plans for another fly fishing adventure. My initial thoughts revolved around South Boulder Creek, but when I checked the flows, I noted that they elevated from 5.6 CFS to 80 CFS in one single twist of the valve on Monday, so I was concerned that the dramatic change would impact the willingness of the trout to feed. I am convinced that large changes in stream levels require a period of adjustment for the cold water inhabitants. I moved on to look at other Front Range possibilities. I settled on the Big Thompson River, as the flows were 60 CFS, the high temperatures in Estes Park were in the 65 degree range, and fly shop reports were favorable. Based on past experience, I knew that 60 CFS represented nearly ideal flow rates.

Deep Run

I arrived at the highway pullout by 11AM, and the air temperature was 57 degrees. I wore a long sleeved undershirt, but that was the extent of my layering, as I was convinced that the temperature would quickly warm to comfortable levels. For my casting tool I chose my old Sage four weight, and after I hiked down the road a decent distance, I waded into the river (more like a creek) and began fly fishing at 11:30AM. To start my advance on the local trout population I armed my line with a size 8 tan pool toy hopper, a salvation nymph and a beadhead RS2. Quite a few flying grasshoppers flushed from the roadside vegetation, as I strolled along the shoulder of the road, and this prompted my choice of the pool toy hopper. Fall baetis hatches are prevalent on Colorado streams; and, thus, the RS2 nymph assumed a position on the end of my line.

In the first thirty minutes I progressed a short distance upstream, and I managed to fool one small six inch brown trout on the salvation nymph, before I adjourned for my lunch break on a wide flat rock in full sunshine. I also momentarily hooked a better fish on the hopper and temporarily connected with a smaller finned resident on one of the nymphs. Three refusals to the hopper were also part of the morning experience.

Nice Pastel Colors

After lunch I decided to downsize, and I replaced the hopper with a peacock hippie stomper while allowing the other nymphs to remain in place. In a short amount of time a small rainbow trout grabbed the hippie stomper, but then I suffered through an extended period with only stomper refusals to show for my efforts. I paused to reevaluate, and I concluded that the nymphs were not a desired food source, as nearly all the interactions with trout were on the surface. I nipped off the nymphs and replaced them with a size 14 light gray deer hair caddis on a twelve inch dropper. The stomper/caddis combination yielded a small brown trout that grabbed the caddis; however, most of the activity involved refusals to the hippie stomper.

Looks Promising

Respectable Brown Trout

Edge Water Produced

I removed the distracting hippie stomper and settled on a solitary deer hair caddis as my offering. I focused my casts to the small slow pools along the edge of the river, and I was rewarded with four very nice brown trout. This portion of my day elapsed between 1:00PM and 2:15PM. Eventually the caddis began to generate refusals as well, but I observed fairly frequent rises to surface foods that were too small to detect. I suspected a mid-afternoon blue winged olive hatch, so I clipped off the caddis and replaced it with a CDC BWO.


Rising Fish in This Area

The transition to the CDC BWO occurred, as I approached a long smooth pool that spanned the entire riverbed, and sporadic rises appeared throughout the pool For the next hour I cast the CDC BWO to rising fish, and I managed to boost the fish count from seven to ten. Two of the landed fish were medium sized browns; however, one was a very respectable chunky twelve inch rainbow. I made a significant number of casts throughout this time period, and the fish were by no means competing for my fly. Quite a few regular risers absolutely ignored my fly, and quite a few more looked at and refused the small CDC puffs. I swapped the CDC BWO for a soft hackle emerger fished with floatant on the body, but this ploy was ineffective. Near the end of my time on the water I converted to a size 22 CDC BWO with a small medium dun hackle, and this duped the rainbow trout, but it was also refused and ignored as frequently as the CDC BWO without hackle.

Flipped Around

By 3:30PM I progressed to the top of the run and pool, so I retreated along the south bank and crossed at the shallow water near the tail. The shadows lengthened across the river, and the absence of the sun’s rays sent chills through my back. I could have added my raincoat for an extra layer of warmth, but I attained double digits, and it was 3:30 and time to make the drive home.

Tuesday was a fun bonus day of fly fishing after another bout of illness, and I appreciated it. The action was not fast and furious; however, I managed to reach double digits, and at least four of the trout measured in the eleven inch range. Fishing dries in October is always appreciated, and I managed to formulate tactics to net a few nice fish with the caddis along the banks of the river. The weather is supposed to cool significantly over the next few days but then return to warmer temperatures Sunday through early next week. Perhaps I will post another fishing report before the cold weather moves in to stay.

Fish Landed: 10