Time: 10:45AM – 3:00PM

Location: Below Gross Reservoir

South Boulder Creek 07/21/2026 Photo Album

My fly fishing adventure on Tuesday, July 21, 2026 contained some interesting developments. On Monday I experienced an average day on the South Platte River, and in spite of choosing a tailwater for my angling location, the water temperature registered 68 degrees, when I dipped my thermomenter in the river at 1:00PM. Flows of 108 CFS were not enough to buffer the bottom release water against air temperatures in the mid eighties, and it is not even August yet. What is an avid fly fisherman to do?

So Many Speckles

I regularly check the flows on South Boulder Creek, and when I reviewed the graph on Monday evening, I noted that the water was being released from the bottom of Gross Dam at 92 CFS. That was all I needed to see, as the narrow streambed and bottom releases would surely maintain temperatures conducive to coldwater fish. As I prepared to write this blog on Wednesday, I checked the DWR information again, and the flows actually dropped from 92 CFS to 77 CFS, while I was fishing in the tailwater creek.

Doing the Heavy Lifting on This Day

The temperature in the parking lot was in the upper seventies, so I was once again prepared for a hot day. On this stream my feet get numb, even when I wear my waders, so I decided to not wade wet, even though that option would have been advantageous for the inbound and outbound hikes. A little perspiration never hurt anyone. For my rod I chose my Loomis two piece five weight. I like the softer action of the Loomis for throwing dry/droppers and dry flies, and the shorter length also appeals to me among the tighter surroundings of a narrow creek.

Monster for SBC

I arrived along the stream by 10:35AM, and I was prepared to cast by 10:45AM. There were five cars in the parking lot, and as I hiked along the trail next to the creek, four or five anglers were spaced out throughout the section that I targeted. I selected that section because I was convinced that fishermen would avoid the relatively steep sided banks and opt for gentler terrain. I was wrong, so I hiked quite a bit beyond the initially chosen section.

Nice Brown Taken from Under Overhanging Branches

All aspects of fly fishing in Colorado in 2026 have been earlier than normal including stream levels, water temperatures and insect hatches. Based on this knowledge I decided to begin with a parachute western green drake. Normally green drakes hatch during the first week of August, but I was curious to see if they were present on July 21. My thought process was sound, but the green drake was totally ignored in my first fifteen minutes of fishing through some very attractive pockets and runs.

The Brown Trout Parade Continues

I decided to explore another pathway, and I substituted a size 14 yellow stimulator and size 16 light gray deer hair caddis. I prospected with this combination for an hour, before I broke for lunch at 11:45AM, and I pushed the fish count to three. One of the landed trout was a brown in the thirteen to fourteen inch range that clobbered the caddis beneath some low hanging branches. This was a highlight, as it was the longest fish of the day, and it required some pinpoint casting accuracy.

Lip of the Rock Contained a Decent Brown Trout

While eating lunch on a large boulder, I spotted two western green drakes, as they floated upward like helium balloons. Surely the trout would now tune into my green drake imitation.

Another Decent Rainbow

I removed the double dries and tied on the parachute green drake for a second trial run. Nothing developed from the move other than a couple refusals. Maybe the trout were looking for a bushy fly that better imitated a large mayfly attempting to become airborne? I swapped the parachute green drake for a user friendly green drake. Once again the trout ignored my offering.

Small Pool

As I was working upstream, another angler popped into my field of vision. He was hidden behind a small bend and some trees. I attempted to talk to me, but I was unable to hear him over the sound of the rushing water, so I waded to the right bank, and he met me half way. He left the section between me and where he first appeared untouched, and he was moving downstream fishing streamers. He also informed me that he encountered a bull moose not too distant upstream. He said it was along the right bank in the shade between the creek and the trail. I filed this away, but I expected the moose to have moved on by the time I reached the position that was described.

Chunky Rainbow

The green drake ploy was not effective, so I abandoned it, and returned to an olive body size 14 stimulator and the light gray deer hair caddis. While I moved upstream with this combination, I observed another four or five green drakes. No matter. I persisted with the stimulator and caddis and boosted the fish count from three to seventeen. A few of these trout smacked the stimulator, but the caddis was by far the main attractor. I was rather amazed at how aggressive the trout were for the small size 16 caddis, particularly in riffles over moderate depth. Another popular position for feeding trout was the cushion in front of a large rock or at the lip of a pool, where the current accelerated.

Looks So Good

By two o’clock the temperature was spiking, and the yellow stimulator began to induce refusals. I considered my options, and I guessed that perhaps a peacock body hippie stomper might be a more effective lead fly than the stimulator. I made the change, and sure enough, it worked. Of course, the move was accompanied by refusals, but the hippie stomper accounted for two nice trout, and the caddis registered another three to boost the fish count to twenty-two. I was rather satisfied with my day at this point, and I considered calling it quits. The heat was intense, and I suspected that the trout would turn off in response.

Mr. Moose

I was approaching a large bend in the creek, when suddenly the branches next to the stream parted, and a massive and very dark moose made an appearance. I froze. The moose was no more than ten yards away, and it towered above me. I always underestimate the height of a moose with its long legs and high antlers. The moose and I stared at each other for thirty seconds, and my heartrate skyrocketed. What was I to do? I was stuck in the middle of the small creek, with no easy exit path. I slowly grabbed my line and hooked the fly to the rod guide, and I turned my body to slowly wade to the opposite bank, where there was an opening in the bushes.

From Upstream. Keeping an Eye on Me.

When I reached the bank, I turned around to check on my fishing buddy, and the moose bent its long legs and collapsed in the shallow water of the creek. Apparently moose do not handle the heat any better than humans, although this male had the good sense to wade wet. I concluded that a moose wallowing in the cool creek was not about to charge me, so I removed my camera and snapped three photos and a video. My heart rate slowly crept downward, and once my photography duties were complete, I climbed a path to the top of the bank and circled around the relaxed moose. Now that it was over and my fear waned, I was euphoric with the sighting.

I stopped and fished for another ten minutes at another favorite section on my return hike, but after that I returned to the parking lot and called it a day. And what a day it was! I encountered green drakes, and although my flies did not produce, I consider it a positive sign that green drake action will elevate from here. I landed twenty-two wild trout, and this included a fourteen inch brown and a nice thirteen inch rainbow. I estimate that four of the landed fish were rainbows with the remainder browns. The deer hair caddis was a winning fly and accounted for most of my landed fish. If the water level remains in the 70 – 100 CFS range, South Boulder Creek will be a solid option, while the heat wave and drought take its toll. I’ll never forget the close encounter with a moose on the loose.

Fish Landed: 22

Time: 11:00AM – 3:30PM

Location: Below Gross Reservoir

South Boulder Creek 04/07/2026 Photo Album

Not all outings can be as rewarding as those that I experienced early in the 2026 season. Tuesday qualifies as a disappointment in my book. Flows on South Boulder Creek were held steady at 90 CFS, and I knew from previous visits that flows at that level were very conducive to fly fishing. The high temperature in Eldorado Springs was expected to reach 61 degrees, so I decided to make the trip.

Upstream

I arrived at the Walker Ranch Trailhead parking lot and quickly prepared to fish. The dashboard temperature was 51 degrees, and that was surprising since the reading was in the thirties as I passed through Boulder, CO. I pulled on my fleece hoodie and stuffed my raincoat and a long sleeve undershirt in my backpack along with my lunch. I selected my Loomis two piece five weight for my casting tool, and I departed on the one mile downhill trail. I knew I would pay for the downhill on the return, but that is part of the South Boulder Creek bargain.

First Fish of the Day

I began my day with a peacock hippie stomper and size fourteen deer hair caddis on the off chance that the fish would be looking up. No dice. After twenty minutes of inaction, I converted to a dry/dropper configuration that included an amber ice dub body chubby Chernobyl and a psycho prince. The combination was equally ineffective, so I swapped the psycho prince for a regular prince, and the pairing was ignored. I suspected that I was not drifting deep enough, so I added a second nymph in the form of a hares ear. Once again no response was forthcoming. Finally before lunch I swapped the hares ear for an olive perdigon to gain depth, but my morning ended with a fish count of zero. I did note a refusal to the chubby Chernobyl, and I temporarily hooked a fish on the chubby as well.

Another View of My Favorite Pool

The sun was out bright, so I removed my fleece hoodie and knotted it around my waist under my waders. It worked, but the fit was rather tight. It was obvious that the trout were not interested in nymphs, so I abandoned that approach and returned to a double dry fly gambit. I pulled a classic Chernobyl ant from my box and placed it in the first position, and then I added a deer hair caddis. Between 12:30PM and 2:00PM I cycled through a number of dry flies, but I could not unlock the code. There was the hippie stomper, a yellow stimulator, a size 14 olive-brown deer hair caddis, a size 14 gray stimulator, a black parachute ant, and a Jake’s gulp beetle. The stimulators and caddis provoked refusals, but my fish count remained mired on zero.

Handful

At this point I encountered a gorgeous pool; my favorite on the stream. The hippie stomper and beetle remained on my line, but the shutout continued. I swapped the beetle for a size 16 olive-brown deer hair caddis, and I nicked a small trout, but then the creek residents once again ignored my offerings. I waded to the tail of the pool below the right bank, where some side channels fed into the pool in some short runs. I could see quite a few trout in front of me, and they were rising and sipping something small on a very irregular basis. I tried an ant and a CDC BWO, and I was able to monitor the reactions of three very respectable trout to my right. They ignored my offerings. Finally I decided to try the new kid on the block, the mole fly. Guess what?Two trout charged to the surface and smacked the mole, and I was on the board with two landed fish.

Home to a Lot of Fish

I persisted with the mole fly for another fifteen minutes, but it was treated like inert flotsam. I cycled through a soft hackle emerger fished dry and a tiny CDC BWO, but those flies were ignored, so I moved above the pool. The next set of attractive pockets were much faster moving, and the tiny baetis imitations seemed futile without actually seeing rising fish, so I reverted to the size 14 olive-brown body deer hair caddis. Once again I only exercised my arm, so I exited and began my arduous return hike.

Take Two

When I reached a spot, where I was forced to wade along the edge to progress back to the car, I paused to make some casts, and much to my amazement, I landed a small rainbow and a small brown trout. This lifted the fish count to four, and I was very thankful for that meager tally. I returned to the fishermen path and hoofed back to the car. During the one mile uphill I paused every .3 miles to drink water, catch my breath and rest my muscles. I made it.

Wide Pocket Yielded

Tuesday was a very slow day. There were very few insects present, and that may explain the lack of action. I tried quite a few flies and methods, but none delivered consistent results. I will probably give South Boulder Creek a rest before I return.

Fish Landed: 4

Time: 11:00AM – 3:30PM

Location: Below Gross Reservoir

South Boulder Creek 10/22/2025 Photo Album

What a day! October 22 is kind of late in the season for this fair weather angler, but the high in Denver was projected to climb into the seventies, and when I checked the two locations close to my intended fishing destination, the weather indicated temperatures in the sixties. I decided to pay an autumn visit to South Boulder Creek.

Source of Early Trout

The flows were reduced at 17 CFS, but I knew from previous experience that I fished successfully at 10 CFS. Low clear flows would dictate stealthy approaches, longer casts and light flies. I was prepared.

So Pretty

I arrived at the Walker Ranch Loop Trailhead, and I quickly geared up with my Sage R8 four weight. For clothing I wore a short sleeve high tech undershirt and my fishing shirt, but I loaded my backpack with my raincoat and a long sleeve Under Armour shirt. If I perspired excessively, I planned to change undershirts, before I began to fish.

Another Early Rainbow Trout

There were three cars in the parking lot besides my Telluride, but none of them were obviously fishermen. In fact, I never saw another angler during my entire time on the creek, nor did I encounter any on my hike to and from the stream. I had the entire small tailwater to myself. Perhaps the low flows scared away other anglers.

Shelf Pool

As I descended the trail to the creek, I heard the sound of heavy equipment operating to the west. Almost instantly I went into panic mode, as I envisioned the 17 CFS as a muddy mess from excavation taking place at the dam expansion site. You can imagine my relief, when I caught my first glimpse of the creek, and it was crystal clear.

Stealth Required

When I finally arrived at my chosen starting point, I concluded that I was perspired but not to the degree that I required a shirt change. I began my quest for South Boulder Creek trout with a solo peacock size 14 hippie stomper, and the dependable fly yielded three fish including a nice eleven inch brown.

Fine Rainbow Trout

After the early success, the trout’s interest in the stomper seemed to change into observation, and refusals ruled the day. I paused at 11:45PM to enjoy my lunch, and then afterward I replaced the hippie stomper with a size 14 olive deer hair caddis. The caddis produced a few fish to boost the fish count to seven, but it was very difficult to track in the glare and shadows, and it also elicited some refusals.

Next to the Exposed Boulder Was a Target

My mind went into overdrive, and I considered the idea of a beetle. Hatches are rare late in the season, but the 2025 autumn has been unusually mild thus enabling the survival of terrestrials. I knotted a size 14 Jake’s gulp beetle to my line, and I added a sunk ant on an eighteen inch dropper. Large black ants are quite prevalent in the South Boulder Creek canyon.

Very Nice Brown for a Small Stream

The move paid handsome dividends, and I built the fish count to eighteen, before I once again stalled. Five of the eaters during this span of time gobbled the sunk ant, but the rest sipped in the beetle. In addition I experienced many temporary hook ups, where the trout nipped the beetle, and I set and connected, but the fish wriggled free in a short amount of time. Beetle takes are very subtle probably because the small foam fly rides low in the water, and the fish dart to the surface and execute a quick sip.

Another Brown Trout Run

When I got stuck at eighteen, I began to notice an increased number of airborne insects over the water. The naturals included small caddis, a couple mayflies and a stonefly. This observation prompted me to swap the sunk ant for a size 16 gray deer hair caddis. The beetle and caddis combination raised the fish count from eighteen to twenty-four; its final resting place before I quit and completed the exit hike.

Large Tail

Twenty-four trout landed on a fall day in October is very satisfactory, but of course, many of the fish were small and in the six to nine inch length slot. However, I also landed a fat thirteen inch rainbow and two fourteen inch brown trout that challenge for the largest browns that I ever landed in South Boulder Creek. The second brown smacked the caddis near the end of the day.

As predicted, the weather was gorgeous. I had the stream completely to myself and the beetle was a solid attractor. I took advantage of one of the remaining nice days of 2025, and I am pleased with the results.

Fish Landed: 24

Time: 10:30AM – 3:00PM

Location: Below Gross Reservoir

South Boulder Creek 08/27/2025 Photo Album

I was a bit under the weather on Tuesday after over exerting and not drinking enough fluids on Monday, but I made plans to fish South Boulder Creek with my young friend, Nate. It had been quite a while since Nate and I fished together, since his job and pursuit of a career dictated higher level priorities. However, with a short break in his education, we managed to meet up on Wednesday, August 27, 2025.

Because of my concern over my weakened condition from illness, I parked at the kayak lot, as this allowed a shorter albeit steep return hike at the end of the day. The sky was overcast, and the temperature was in the mid-sixties, as Nate and I prepared to fish. I selected my Loomis two piece five weight for my day on the creek. Flows were steady at 100 CFS.

Lunch View

We were positioned along the creek by 10:30AM ready to cast. I began with a solo parachute drake with the hope that the trout had a long memory for western green drakes. In the first decent pool I witnessed five refusals to the parachute green drake. Needless to say, I was very disappointed. I tested it in a few more promising spots, but fairly quickly I converted to a dry/dropper featuring a size 8 tan pool toy hopper, a prince nymph, and a salvation nymph. I never really got a read on this combination, as all three flies separated from my line for some unknown reason, probably a bad knot connecting to the eye of the hopper.

Amazing Color

When I rigged anew, I switched to a peacock hippie stomper and an olive perdigon. Nate was having quite a bit of success with his dry/dropper, and one of his nymphs was a perdigon similar to a rainbow warrior. I managed to land two small brown trout on the perdigon, but then I suffered through a lengthy time period with no action in spite of some very attractive creek structure. I finally ended the late morning frustration by wading to the bank to find a decent resting spot to eat my lunch.

Cannot Wait

Since Nate was faring quite well after lunch with his dry/dropper, I reverted to that approach. I knotted another tan pool toy hopper to my line and then followed it with an ultra zug bug and a size 18 pheasant tail nymph. The pool toy hopper suddenly worked some magic, and I landed two decent rainbow trout in the eleven to twelve in range on the foam terrestrial. Next, a fish grabbed the pheasant tail, and suddenly I was in the realm of respectability at five fish landed. Another trout grabbed the ultra zug bug, and then Nate and I spotted some natural green drakes floating above the creek.

Sleek Look

Nate quickly switched to a green drake, and he immediately netted a couple fish. This was the impetus I needed to make the same change, and I placed a size 14 parachute green drake on my line. For the remainder of my time on South Boulder Creek I fished green drake patterns including the paradrake, a user-friendly geen drake, and a comparadun green drake. The fish count climbed from six to eleven, and most of the takes were instigated by the parachute green drake.

Hit the Pocket

Although I enjoyed the two hours of green drake prospecting, the episode was nothing like my experience on my two previous visits to South Boulder Creek during the green drake hatch. The fish were very discerning, and I probably had one refusal and one temporary hook up for every fish that I landed. I rotated among the green drake styles, but none of them delivered the consistency that matched my earlier trips.

Backhand Casting Wizard

The highlight of the day occurred around 2:30PM. I was presenting a double dry with the user friendly in the forward position and the parachute green drake trailing. I made a reach cast across some currents and created a long drift over a relatively smooth slide of moderate depth, and suddenly I spotted a take just as the flies were set to drag before the lip of the run. I swiftly set the hook and immediately saw the side of a substantial brown trout flash. Eventually after a spirited battle, I slid my net beneath a fifteen inch brown; a giant by South Boulder Creek standards. Needless to say, this made my day.

Last and Best Fish

We both quit at 3:00PM, when we reached a narrow streambed that created fast whitewater. We were tired and not up for continuing, so we hooked our flies to our rod guides and made the return hike. Although Wednesday did not measure up to earlier South Boulder Creek green drake outings, it was a success nonetheless, and I valued my time with Nate. Nate’s fly fishing abilities have advanced measurably, and he accumulated fourteen fish on the day. I, in turn, landed eleven. All our fish were hard earned, and two double digit fish counts were worth a gorgeous day on South Boulder Creek.

Fish Landed: 11

Time: 10:30AM – 2:30PM

Location: Below Gross Reservoir

South Boulder Creek 08/12/2025 Photo Album

I recently spoke to my son and suggested that we should plan a day of fishing on South Boulder Creek, now that the flows were reduced to 104 CFS, and the trout were tuned into western green drakes. He checked his work schedule, and we agreed to follow through on a day of fly fishing on Tuesday, August 12, 2025. Dan lives in Louisville, CO and has two young boys, so the opportunity to fish with him is infrequent and highly valued by this dad.

Dramatic Colors

I met Dan at his home in Louisville, since it is on the route to the Walker Ranch Loop Trailhead. I switched my gear to his car, and he drove the winding and steep road through Flagstaff Mountain Park to the parking lot at the trailhead. The high temperature in Denver was forecast to hit the upper nineties, so we knew it was going to be a hot one, but I was reluctant to wet wade, as the cold flows from the bottom release dam make me feet cold, even when I wear thick socks and waders. We both wore our waders and suffered, especially on the one mile hike up the hill at the end of our day. I chose my Loomis two piece five weight, because it is less than nine feet and offers a slower action for casting dry flies.

Very Productive Pool

By 10:30PM we were perched next to the creek. Dan commanded the left side of the stream, and I advanced along the right bank. We both began with parachute green drakes, and we were not disappointed. We experienced some refusals, but for the most part the trout were where one would expect them to be, and they liked our green drake imitations.

Dan Focused

By noon we met on my side of the creek, and my fish count rested on ten, while Dan accumulated seven. After I devoured my peanut butter and jelly sandwich and a few other snacks, we resumed our progression. As is usually the case with green drakes, the fish became more selective after lunch, and refusals and looks became problematic. Dan switched to a user friendly, after I gave him one at lunch time, and he began enjoying some success.

Pretty Brown Trout

I, on the other hand, did not fare as well with the user friendly, so I progressed to a size 14 green drake comparadun. This fly enabled me to boost the fish count by five, but the olive and brown low riding fly was very difficult to track, especially in shadows and glare. Dan persisted with the user friendly with decent success, so I reverted to that fly. I observed three natural green drakes during the 1:00PM to 2:00PM time frame.

Chunky

The final switch to the user friendly proved somewhat successful, and I moved the fish count to twenty-one by the time we quit at 2:30PM. The foam green drake imitation was not perfect, as I experienced quite a few looks and refusals. The easy pickings of my previous trip to South Boulder Creek were clearly a thing of the past. Dan, however, continued to progress upstream along the south bank with quite a bit of success, and he ended his day with a fish count in the same ballpark as my twenty-one. Forty plus fish in 3.5 hours of fishing was certainly a fine day.

Long Pocket

At 2:30PM we began our return hike, and I endured the one mile unending climb to the parking lot with at least five rest stops and water breaks along the way. What a fun day! We both commented on the feeling of remoteness, even though we were only a half hour away from Boulder, CO. When we first arrived, Dan pointed out an eagle, as it glided across the creek below us. On the drive back we encountered a wild turkey, as it shuffled across Flagstaff Road. Standing in the cold creek on a hot day was very pleasant, even though we wore waders. The trout were hungry for green drakes, and we eagerly met their needs. Hopefully I can record a few more green drake outings during 2025. Spending a day with my son was a rare opportunity and highly treasured. That companionship was more valued than any of the trout landed on Monday.

Fish Landed: 21

Time: 10:00AM – 3:00PM

Location: Below Gross Reservoir

South Boulder Creek 08/04/2025 Photo Album

I always keep my eye on the DWR graphs for South Boulder Creek below Gross Reservoir, and I noted that the flows dropped to the 144 CFS range over the most recent seven days. This could only mean one thing; game on for fly fishing SBC. I reviewed my posts for South Boulder Creek for late July and early August, and I learned that I hit green drakes on August 3, 2022. Could 2025 also be an early western green drake year? Read on.

Spectacular Colors

By the time I made the drive, assembled my Loomis five weight and hiked to my chosen fly fishing spot it was 10:00AM. The temperature in the parking lot was 69 degrees, but the high in Eldorado Springs, the closest town, was projected to hit the upper 90’s. I knew it was going to be a hot one. Needless to say, by the time I was ready to fish, I was a bit damp. The flows were, in fact, 144 CFS, and the creek was clear. These flows were higher than I prefer, as they limited my mobility, but the presence of green drakes offset flow shortcomings.

Bankside Pool Was Productive

I began my day with a size 14 parachute green drake. This has become my favorite western green drake pattern, although I carry five different types. As it turned out, all the trout I landed on Monday grabbed a green drake pattern. I did have to test different patterns, however, throughout the day, when one fell out of favor.

Nice Small Stream Brown Trout

Between my start and 11:45AM, the parachute green drake fooled twenty trout. Yes, the fishing was torrid. In nearly every location that looked like it might hold fish, a trout emerged to crush the green drake. It was not always the first cast, but quite often that was the case. I quickly discovered that the fish avoided the pockets and slicks in the middle of the river, so I confined my casts to the likely holding lies along the banks. There were a few places, where I was able to maneuver enough to launch some casts to the opposite bank, but for the most part this gambit was not effective. Upstream casts along the right bank were the most productive. In addition, some places were wide, and this allowed the creek to spread-out and create moderate riffles and pockets, and I was able to wade to the middle to cover all the likely spots.

Parachute Green Drake Was Popular

I continued with the parachute green drake after lunch for fifteen minutes, but suddenly the trout consistently refused the previously hot fly.  This was a common occurrence during previous year outings, and my reaction was typically to switch to a green drake comparadun. I followed tradition, and the comparadun delivered and moved the fish count from twenty-five to thirty-one. However, the low riding fly with a large high wing was also refused, and it was very difficult to track because of its earthy colors.

Slender Look

I grew frustrated with the low visibility and the inability to follow, so I made another exchange. In this instance I substituted a user friendly green drake. This fly was designed by Andrew Grillos, and it is very similar to a hippie stomper. It possesses a different wing, and I modified it to display the green drake colors. I have had some previous success with the user friendly, but I consider it a third option behind the paradrake and comparadun. Well, guess what? It became a hot fly. I improved the fish count from thirty-one to sixty-two on the back of a user friendly. I tested it, because I suspected that the fish were looking for a wider and bushier profile, and the user friendly possesses those qualities. In addition, the foam strip makes the fly very buoyant, and the white wing enhances visibility. It worked better than I ever expected.

Wide Bank Pool to Explore

By 3:00PM I was weary, and I reached a point where significant rock scrambling was required to continue an upstream progression. I faced a one mile ascent to the parking lot, and I was depleting my energy supplies. I called it quits and hiked back to the car.

Face Down

What a day! Of course, many of the trout landed fell in the six to eight inch range. Nevertheless, there were enough brown trout and rainbow trout in the ten to twelve inch slot to keep me focused. I love prospecting with a single dry with the knowledge that the fish were tuned in, and I could expect a response in nearly all promising spots. In fact, quite a few marginal locations also generated takes. The rainbows were on average a bit larger than the browns, although I never landed a fish from either species longer than a foot.

User Friendly Green Drake

Hopefully I can return in the near future when the green drake hatch intensifies. I saw one natural green drake during my entire stay on the creek, but the trout were certainly aware of their presence. A modest drop in flows that offered better wading conditions would also be welcome. Stay tuned.

Fish Landed: 62

Time: 11:15AM – 3:00PM

Location: Below Gross Reservoir

South Boulder Creek 05/04/2025 Photo Album

I normally avoid fly fishing on weekends, but on Sunday, May 4, 2025 I made an exception. The weather forecast for Monday through Wednesday of the upcoming week portended adverse fishing conditions, so I made the trip to South Boulder Creek. I kept my eye on the flows below Gross Reservoir, and they remained steady at 45 CFS for more than a week. These flows are a bit low for my preference; however, I have enjoyed success at even lower levels. The high temperature in the canyon was forecast to reach the mid-sixties, so that also played into my decision.

By the time I made the relatively short drive and jumped into my gear and hiked to the creek, my watch displayed 11:15AM. My trip through Flagstaff Mountain Park was slowed by a caravan of cyclists climbing the steep and winding road. Kudos to all the riders who finished the ascent.

Covered in Spots

The parking lot at the Walker Ranch Loop Trailhead was nearly full, but I lucked out and found a recently vacated slot. I wore my fleece hoodie, but I avoided my long sleeve undershirt and stuffed my raincoat in my backpack. The temperature at the parking lot was 61 degrees. I have been using Pinecliffe, CO in Weather Underground as my proxy for weather at South Boulder Creek, but I concluded that the higher elevation mountain village probably understates the air temperatures in South Boulder Creek below Gross Reservoir.

Narrow Ribbon of Fishable Water

To begin my quest for trout I began with a peacock size 14 hippie stomper and then added an olive perdigon on a three foot dropper. Beneath the perdigon I knotted a size 20 salad spinner midge pupa imitation, and I began to probe the likely fish holding lies. In a short amount of time I landed a small brown trout barely longer than my six inch minimum, and it grabbed the perdigon.

Stripe Separate from Cheek

As I began my move to the next attractive spot, I noticed two anglers not more than thirty yards above me. I did not pass another fisherman during my entire inbound hike, yet two competitors showed up within a stones throw of my position! Needless to say I was disappointed, so I stripped in my line and secured it and circled around the invaders of my sacred space.

A Brown Joins the Fun

I hiked .25 mile to give them space, and then I angled back to the creek in a place where I enjoyed decent success in the past. I once again began to probe the pockets, runs and riffles; and I added three rainbows to bring my fish count to four by lunch time a bit before noon. During this time I abandoned the salad spinner and replaced it with a beadhead hares ear nymph and a bright green caddis pupa, but all the action came on the olive perdigon and hippie stomper.  I quickly munched my sandwich and carrots, and then I resumed my prospecting, but guess who I spotted thirty yards above me? It was my nemeses. I saw one of them look back, and they spotted me, so they quickly moved out of sight. I made a mental note of where they were first noticed, and then I fished to that spot and pondered my next move.

Nice Bankside Run

I suspected that they exited and left the next stretch undisturbed, but I could not be sure, so I once again cut over to the trail and worked my way up the path. I found them just downstream of my favorite pool, so I stealthily bypassed them and hoofed quite a distance before re-entering the creek. I estimate that I hiked at least half a mile to allow them space.

As I recall, the fish count was now at six, and during the remaining time on the water, I elevated it to seventeen. The hares ear and caddis pupa failed to generate any action, so I replaced them with a sparkle wing RS2, and I kept the hippie stomper, perdigon, RS2 combination in place for quite a while.

Scene of Rising Fish

At 2PM I approached a gorgeous long pool with a deep run flowing down the center. Just before arriving, I experienced quite a few refusals to the hippie stomper, so I decided to remove the nymphs and transition to a double dry with the hippie stomper and a size 16 olive-brown body deer hair caddis. The caddis fooled one fish, before it created some refusals, and I began to spot a few random rises. My hunch told me that blue wing olives were emerging, so I replaced the caddis with a CDC blue wing olive.

Brilliant

I persisted with the double dry for the next hour, and I added four more trout to bring the total to seventeen. For some reason the stream residents began to smack the hippie stomper, when it was combined with the tiny CDC BWO.

The Workhorse Fly on Sunday

By 3PM I once again bumped up against a trio of anglers, so I decided to call it a day, and I completed the arduous one mile steep ascent from the creek back to the parking lot. The weather was perfect, and I landed seventeen fish, so I cannot complain. Nevertheless, the size of the trout was lacking, with the largest perhaps in the eleven inch range. Oddly the ratio favored rainbows with probably seventy percent of the pink striped variety. The rainbows more than made up for their lack of size; however, with their brilliant colors and spot patterns. I must admit that the competing anglers were a pain, and I missed my normal solitude enjoyed during weekday stream visits.

Fish Landed: 17

Time: 11:00AM – 3:45PM

Location: Below Gross Reservoir

South Boulder Creek 10/22/2024 Photo Album

After a tough weekend battling a cold relapse, I found some solace in the fact that the weather wasn’t all that inviting for fishing either—cold and wet. But by the time Monday rolled around, unseasonably warm weather made its way into Colorado, presenting an opportunity I couldn’t pass up. With the sun shining again, I set out for a much-needed day on the water.

Typical Pocket in the Morning

Another Great Spot in the Morning

The first stream that I reviewed was South Boulder Creek below Gross Reservoir, and I was relieved to see flows at 82 CFS—a much-needed improvement after weeks of meager trickles around 6.7 CFS. However, a scare came early Tuesday morning, when I noticed a spike to 97 CFS. Thankfully, by the time I checked again, flows had returned to 82 CFS, holding steady as I prepared to head out. Oddly enough, when I returned home later that day, I found the flows had dropped to 65 CFS, while I was on the creek, which is nearly perfect for me. It turned out to be an ideal day to hit the water.

Right Area Next to the Bank Was Typical of Very Productive Water

Stunning Colors

I arrived at the trailhead around 10:00 AM, greeted by a brisk 56-degree temperature and a stiff breeze. For the hike in, I wore my usual fishing shirt layered over a short-sleeve undershirt, but packed an extra long-sleeve Under Armour layer just in case. The air was cool, but comfortable enough that I never felt the need for a clothing change. By 11:00 AM, I reached my starting point along the creek and rigged up with my favorite fall setup: a peacock Hippie Stomper trailing an ultra zug bug and salvation nymph.

Wide Productive Section

Feisty Rainbow

The morning session proved to be steady, although the wind and the shade made things feel colder than expected. The combination of light sweat and the breeze led me to put on my raincoat for some added warmth. Despite the chilly start, I landed four fish by the time I broke for lunch at noon—three small browns and one small rainbow trout. Although none of the fish were large, they were a good start to what would become a fruitful day.

After lunch, the fishing picked up. I continued upstream, sticking with the dry/dropper setup that had brought success earlier. By mid-afternoon, the fish count rose to sixteen. The catch was evenly distributed: eight fish smashed the Hippie Stomper, while the ultra zug bug and salvation nymph each accounted for four fish. Interestingly, the ultra zug bug started strong but seemed to lose effectiveness as the day wore on, with the salvation nymph picking up the slack.

Long by Tuesday Standards

Center Slick Looks Prime

Upon reaching sixteen, I decided to change tactics and switched to a double dry fly setup. I kept the Hippie Stomper as the lead, but added a size 14 light gray deer hair caddis on a twelve-inch dropper. The move paid off. The afternoon saw another seven fish come to hand, with half falling for the Stomper and the others grabbing the caddis. Toward the end of the day, I swapped out the size 14 caddis for a size 18, which proved just as effective.

Another Nice Spot Along the Bank

Throughout the day, I noticed an abundance of refusals on the Hippie Stomper—enough to prompt the shift to a double dry setup. Despite the occasional refusals, the overall catch rate using double dries remained steady, and I was pleased with the action.

Near the End of the Day Jewel

Most of the trout landed were on the smaller side, with the largest coming in around eleven inches. Brown trout outnumbered rainbow trout by a two-to-one margin, and the most productive water tended to be the tails of long pockets, riffles, and slower-moving pools near the bank. I was surprised several times by fish emerging from shallow lies, where I wouldn’t have expected to find them.

Probed Both Sides of the Pyramid Rock on Right

All told, I landed twenty-three trout—admittedly small, but each a vibrant testament to the beauty of fall fishing in the foothills of the Rockies. More than half of the trout came to the surface on dry flies, and dry fly action in late October is always a welcome treat. The relatively smaller size of the browns might be a result of their spawning activity, although I didn’t observe any active spawners. With cooler weather on the horizon, future outings will depend on Mother Nature, but I’ll be keeping my gear ready for the next window of opportunity.

Stay tuned for more fishing adventures as 2024 unfolds!

Fish Landed: 23

Time: 11:00AM – 4:00PM

Location: Below Gross Reservoir

South Boulder Creek 08/28/2024 Photo Album

With Labor Day weekend and a trip to Hilton Head Island in my near future, I was facing perhaps my last fly fishing outing until the second week of September. I checked the flows on my home waters, South Boulder Creek, and the water managers cranked down the valve to 100 CFS. It was 122 CFS during my last visit to the tailwater below Gross Reservoir, and that level dictated extreme caution when wading with only a few viable crossing points. The combination of lower flows and the prospect of the presence of green drakes clinched my decision. I made the trip to the Walker Ranch Loop trailhead for a day of fly fishing.

The temperature at the parking lot, when I arrived, was 74 degrees, and I suspect that the reading reached eighty degrees, by the time I hiked out of the canyon at 4PM. I chose my Loomis two piece five weight for my casting tool. Somehow I strained my neck while camping over the weekend, and I felt like the short rod would provide less strain to the neck area, when I lifted the line to make a cast. Also, I planned to toss a double dry fly, and the slow action Loomis is well suited to that task.

Corner Pocket Was Productive

By the time I hiked down the trail to my chosen fishing spot, it was 11:00AM. I selected a peacock hippie stomper from my MFC fly box, and then I added a parachute green drake on a twelve inch dropper. It was slow going initially, as I prospected some very attractive pools and pockets with nary a look, but I persisted with the double dries, and eventually I was rewarded for my patience. In the 1.5 hours before lunch, I landed ten trout, and this included a couple very respectable brown trout and rainbow trout. Initially my best results came from pockets and runs along the edge of the creek, but as time passed, the fish in the larger and more obvious locations began to respond as well.

Plump Rainbow

Early Brown Trout

There was very little strategy on Wednesday, August 28. I fished the double dry consisting of the stomper and paradrake for the entire time, until I stopped at my favorite pool, but more on that later. The parachute green drake was the more productive of the two flies, and I estimate that the catch ratio was 70% paradrake and 30% hippie stomper. The desirable pair of flies in the eyes of the trout accounted for forty fish on the afternoon. The flies were not perfect, as an abundant quantity of refusals and rejecting looks were a significant part of the story.

Photographed Purely for the Color

Along the Rock

Between 12:30PM and 2:30PM, however, the fish were definitely tuned into the green drake. I spotted a handful between 1PM and 2PM, but they were not available to trout in great abundance, I attributed much of my success to trout having long memories for western green drakes.

Long for These Waters

What sort of water was the most productive? Deep slots and potholes around exposed boulders produced some surprisingly nice fish. Also, the lip of pockets and runs, where the water began to accelerate and sluice over the lip was another favorite. On several occasions I gave up on the drift and made a lift just prior to the fly racing over the lip, and I found myself attached to a fish. This always amazes me.

Ooh La La Pool

Brown Trout Perfection

By 3:30PM I decided to call it a day, however, on my return hike I could not resist the temptation to make a few casts to my favorite pool. Upon my arrival I lobbed ten casts with the double dry, but these selective fish were having none of it. While I observed, a flurry of rises commenced, but their target was so small that I was unable to determine the preferred food item. I began to cycle through fly changes, and I replaced the parachute green drake with a size 18 deer hair caddis. It became apparent that caddis was not the answer. Next I knotted a Jake’s gulp beetle as the trailing fly, and it was equally ignored. Finally in frustration I stretched my net seine across the mouth, and I held it in the current for three minutes. When I examined the contents of the seine, I noticed some nymph casings and a crippled mayfly with a dark olive body. I concluded that the fish were responding to a blue wing olive hatch, and judging from their aggressive feeding, I guessed emergers. I replaced the beetle with a soft hackle emerger, and I dabbed the body with floatant to fish in the surface film. This generated a couple looks, but no action. Next I replaced the soft hackle emerger with a CDC blue wing olive, and once again the fish ate naturals in close proximity to my fly. I finally threw in the towel and moved on.

Tucked Under Branches

The prevalent size of trout on the day was eight to nine inches, but I was pleased to land five trout in the twelve to thirteen inch range. Two browns and one rainbow stretched to the upper limit of the size range. The weather was ideal, and the flows were reduced more to my liking, and green drakes were favored by the wild trout. I could not have asked for a more enjoyable fly fishing outing.

Fish Landed: 40