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