Big Thompson River

Big Thompson River

Difficulty Beginner/Intermediate
Ideal Days To Fish 5/16, 5/21 & 5/22

Weekly Report

Report DateMay 12, 2022

Big Thompson flows have held steady at 100 cfs for the past week. At this level, flows are healthy and water clarity is high due to stable flows. This is a great time to fish the Big T as trout are spread out and feeding on a variety of bugs above and below the surface. When nymphing, cover a lot of water and pick apart deep pools, runs, slow riffles, pockets and transitions. Trout will favor the deeper water columns and soft water during the morning, but once water temps rise and bug activity picks up, targeting faster moving water is a lot of fun. Pat’s Rubber Legs, red Copper Johns, Frenchies, Guide’s Choice Hare’s Ears, Flashback PT’s, Rainbow Warriors and Perdigons are productive lead patterns. For your trailer, stick with midge pupa and baetis emergers. Mercury Black Beauties, Mercury Midges, Sparkle Wing RS2s, Darth Baetis and Blue Poison Tungs are good examples. We’re also seeing consistent surface activity feeding during midge and BWO hatches, so be prepared to ditch your nymph rig. While not as prominent, caddis are present and growing in numbers. Keep an eye out for caddis between 10 am and 1 pm. Parachute Adams, Sparkle Duns, Parachute BWOs and olive Elk Hair Caddis are getting plenty of attention on the surface. Small streamers are fun to fish in deeper pools and runs.

Recommended Flies

River Flow

Flow Region
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Detailed River Info


The Big Thompson, commonly referred to as the Big T, is a beautiful river that originates high in Rocky Mountain National Park. This small-medium sized river flows through Rocky Mountain National Park and the town of Estes Park before feeding into Lake Estes. Below Lake Estes, the river continues along Highway 34 through Drake, eventually making its way to the town of Loveland. The Big T flows through various types of terrain, offering anglers a variety of scenic and fishing opportunities. The stretch of river that flows through Rocky Mountain National Park is in an open meadow setting and contains brown trout, rainbow trout, brook trout and if you’re lucky, greenback cutthroat. Below Lake Estes, anglers will find themselves in a canyon setting dominated by pocket water with a select number of deep pools and runs. Brown and rainbow trout in the 10 – 12” range can be found in this stretch.


The Big Thompson is a diverse river that is friendly to anglers of all skill sets. The stretch that flows through Moraine Park in Rocky Mountain National Park is highly sought after during the summer months. During the summer, this stretch tends to see a lot of foot traffic, so stealthy fishing is required to not spook the trout. Fishing dry and dry dropper setups is the preferred method in Moraine Park. Below Lake Estes, pocket water is prevalent, which may test your ability to fish tight pockets. Nymphing is a productive method year-round, while dry and dry dropper setups are productive during the summer and fall. Overall, the ideal time to fish the Big Thompson is during the summer and fall months. However, if you’re looking to fish during the winter, the section directly below the Lake Estes/Olympus Dam is classified as a tailwater and usually remains ice-free.

River Access

The Big Thompson has many access points with varying levels of difficulty. In order to fish Moraine Park, anglers will need to purchase a $25 National Parks day pass. Moraine Park is located just under 3 miles from the Beaver Meadows Entrance Station on the south side of Estes Park. Below Lake Estes, anglers can access the tailwater section via a public park on Mall Rd. Downstream of the tailwater, there are a number of pull offs along Highway 34 that anglers can use to access the river.  Be conscious of private property when fishing along Highway 34. In general, the bank that borders the road is public and the property along the far bank tends to be private.