The "tailwater" section of Blue River through Silverthorne fishes fairly consistently year round. Water temps normally stay within the lower forties (fahrenheit), which doesn’t produce a large variety of hatches. For the most part, small midge larva, and Mysis Shrimp (small white shrimp inhabiting Dillon Reservoir), are staples of the trouts diet. Things start to get more interesting if Dillon Reservoir reaches capacity and “spills” through the top release of the dam, instead of the bottom. This causes a larger variety of aquatic insects that live in the Blue River to become active, and therefore more available to trout.
The best technique is usually nymphing under a small, inconspicuous indicator. Adjust your weight and indicator depth depending on the depth of the piece of water you are working, and to the depth at which the fish are holding. Seeing rising fish is a possibility, as is seeing some action on streamers.
Nymphs To Try: Solitude Mysis Shrimp size 18, Skinny Pheasant Tail size 20-22, RS2 olive or grey size 18-22, BTS Baetis black size 20-22, Thorax Emerger BWO size 20, Buckskin Caddis size 16-18, Pure Midges in black, cream, or olive size 20-22, size 18-22 UV Midge in brown or black, Grey bling Midge size 20-22
Dries To Try: KK’s Henneberry Hopper size 12-14, Hippy Stomper chartreuse size 14-16, Elk Hair Caddis yellow or olive size 16-18, Matthew's Sparkle Dun Baetis or PMD size 16-20, Thorax Emerger PMD size 16, Extended Body Blue Wing Olive size 16-20, Peacock Caddis size 18, Parachute Adams size 16-24, cream Brook Sprout Midge size 20-22, CDC Morgan's Midge size 20-22
Streamers To Try: Barely Legal in Rainbow Trout color, Baby Gongas (olive, black, and rainbow trout), Wooly Buggers (olive, black, white), Pine Squirrel Leeches (black, purple, red), Slump Busters in olive and natural
The Blue River in Silverthorne has steadily declined in flow to 200 CFS over the past week, and we will have to wait and see if it continues to drop or holds at this flow. Dillon Reservoir is still full and water is still spilling into the blue river from the surface of the reservoir. However air temperatures in summit county have been getting much cooler at night, and in conjunction water temps in the blue river have also dropped down near 54 degrees, compared to 58 degrees of last week. We are seeing some sporadic Baetis hatching on overcast days, and some strong midge hatches early morning through mid-day. Both dry fly, and nymph fishing have been effective methods of angling recently. Fish holding along banks or near the surface may be targeted with dry flies, while a nymph rig may be needed if more fish are seen holding near the bottom of the river.
The Blue River through Silverthorne has been holding in flow near 400 CFS for the past week. It is currently in a slow decline with the flow at about 370 CFS, and a water temp of about 58 degrees Fahrenheit. Blue Wing Olives, and Midges have been the main hatches recently, and they are getting the most eats from trout. Small terrestrial insects, and Mysis Shrimp are also getting some attention from trout as well.
At these flows there is soft holding water for trout anywhere from the middle of the river, to the banks. Visually reading water, and sighting trout will be important at this time. A nymph rig, dry flies, or a hopper-dropper set up can all be productive angling techniques at this point in time.
The Blue River through Silverthorne continued to slowly decline in flow throughout the week, and is currently in the mid 400 CFS zone. Water is still being released from both the top, and the bottom of the reservoir, resulting in water temperatures of about 58 degrees. Mysis Shrimp and small aquatic insects are still the main food sources for trout currently. Terrestrial insects and smaller fish, also make up a small percentage of the trouts diet here. Current hatches include Baetis, small PMDs, and midges.
The current flows are allowing trout to hold in more typical lies such as riffles, and deeper holes behind river structure. A nymph rig is a good option at the moment, featuring Mysis Shrimp, mayfly nymphs/emergers size 18-20, and midges size 20-22. Throwing small dry flies along the banks can also produce some hook ups with the warmer water temps, and increased hatches we are experiencing.
The most significant change in the Blue River through Silverthorne this week is the flow. We have seen a steady decrease from the mid 800 CFS range down to about 600 CFS. We cannot be 100 percent sure, but based on the graph of flows this past week it seems that CFS being released from the bottom of the dam is holding steady, while the amount of water draining from Dillon Reservoir’s surface is slowly declining. Water temps are still much warmer than normal, and are currently holding in the mid 50’s. These water temps are producing some decent hatches of BWOs (Blue Wing Olives), small PMDs (Pale Morning Dun), midges, and a few sporadic caddis (we haven’t seen a sizable caddis hatch in town yet).
The lower flows are allowing trout to hold in a variety of water, and they can can currently be found in pockets tight to the bank, as well as deeper seams and holes further off the bank. Use a nymph rig with heavy split shot to get to the bottom of the deeper seams and holes. A light weight nymph rig, dry-dropper, or dry fly set up will all be appropriate options for fishing shallower water along the banks.
The Blue River tailwater through Silverthorne is still holding in flow at about 800 CFS with some variation up and down through out the week. The variation in flow comes from increases in controlled release from the bottom of the Dillon Dam, and from natural fluctuations in flow of the rivers feeding Dillon. Denver Water is the organization controlling water releases from Dillon Reservoir. Several factors including reservoir capacity, and water needs in other locations influence how much water they release from Dillon. Another important factor to remember at the moment is that Dillon Res. is currently hovering near its capacity, so there is some water spilling into the Blue River from the surface of the reservoir. Fishing conditions generally improve during “fill and spill” periods due to slightly warmer temps in the river, which trigger more hatches of aquatic insects. Currently we are seeing hatches of midges, Baetis (Blue Wing Olive), and PMDs (Pale Morning Dun). These insects in combination with Mysis Shrimp, which enter the river system from the dam release, are the top food sources for trout in town t the moment. Terrestrial insects such as grasshoppers, beetles, ants, moths etc. are also more available as we move into mid summer.
A nymph rig with a strike indicator, and split shot is still the most productive rig in town. However, different techniques such as dry fly, dry-dropper fishing have increased trout hooking potential as we start to see more frequent hatches due to the warmer “fill and spill” water coming from Dillon Reservoir.
The Blue River in Silverthorne is currently flowing about 750 CFS. The most notable change in recent conditions is that Dillon Reservoir is in “fill and spill” mode , meaning that water is being released from the surface of the reservoir as well as the usual bottom release. The significance of “fill and spill” is that water temperatures in the river rise a few degrees, which normally triggers stronger hatches of aquatic insects. Currently river temps are about fifty degrees, up a bit from the usual low to mid forties, and we are already seeing the results in the form of Blue Wing Olive hatches. Caddis have started hatching North of Silverthorne where the water temps are slightly warmer than in town, and we should see some small caddis hatching in town soon once temps rise just another few degrees.
From a technique standpoint the Blue River is still high, so we are still targeting calmer pockets of water along banks, or any other “softer” water that is available. A nymph rig is currently the most consistent rig for catching trout, although dry fly, and dry-dropper fishing should become more productive as we see more frequent hatches. A lot of the water in the Blue is still coming from the bottom of the reservoir so don’t discount Mysis Shrimp, they should still be a staple in your nymph rig. Large, natural imitations of cranefly larva, and stonefly nymphs can still be effective at these flows, and they sometimes make a good lead nymph in your set up. Trailing nymphs should include imitations of Baetis (Blue Wing Olives), midges, and caddis larva.
Flows from Dillon Reservoir have dropped to 1080 CFS, down from 1800 CFS. The Blue river in SIlverthorne is still quite high at these flows, but more soft water can be found as these flows. Mysis shrimp will still be the top food source at the moment, but as flows drop aquatic insects will become more and more important. This is especially true if Dillon Reservoir fills all the way up, and warmer water is released from the surface of the lake. Currently the water level in Dillon is holding steady about 6 inches below the surface drain. We often see a strong caddis, PMD, and even Trico Hatch when we get “fill and spill” water flowing into the Blue River. We are currently seeing midges, and a size 16-ish grey colored mayfly dun hatching.
A nymph rig with split shot, an indicator, Mysis Shrimp patterns, and small aquatic insect imitations will still be your most productive set up here. Use a stealthy upstream approach and sight fish to trout in pockets along banks, or “blind nymph” larger areas of soft water. You will need to adjust the amount of split shot, and the depth you are fishing to match each individual piece of water.
We are also getting into terrestrial insect season (grasshoppers, beetles, ants etc.). So if your are inclined to throw some dry flies, try a small hopper, or beetle in tandem with a small mayfly or midge pattern. Target fish sitting in along banks, and especially under foliage as they often eat bugs falling into the water.
The Blue River in Silverthorne has been raised in flow to about 1800 CFS. This is considered high and fast, but it is still very fishable. Fishing tactics will be similar to our last update. Use a stealthy upstream approach and target trout that can be seen sitting in shallow pockets of still water along banks. Also look for smaller side channels, or other pieces of water that have a “softer” more gentle appearance. A nymph rig with an indicator and split shot is your most productive rig here.
Mysis Shrimp are the top food source for trout when river flows are high, because a larger number of shrimp are deposited in the river system from the reservoir where they live. Midges and small mayfly nymphs will be the other staple food sources for trout. Slightly larger food sources such as golden stoneflies, and cranefly larva are sometimes stirred up during higher flows as well.
The Blue is running about 1100 CFS which is very fast, but there is still soft water to found along the banks, and in wider areas of the river. Fishing is not quite as enjoyable from a "wading and casting" standpoint, but trout are easier to target as they can be seen sitting close to the bank. Use a stealthy approach and walk the banks upstream while looking for fish. An indicator rig with a short to medium depth, split shot, and a mysis shrimp/midge combo is a good choice in thees conditions. Some trout sitting under overhanging foliage can also be taken on small terrestrials, small mayfly duns and spinners, or dry midge patterns.
At 600 CFS the Blue River in the town of Silverthorne is considered a bit “high”. However we find that it fishes pretty well at these flows, you can count on fish being pushed to the banks in pockets of calmer water or, stacked in any softer water that is created by larger river structure. Mysis shrimp are an important food source when more water is released from the reservoir, because more shrimp are flushed out with the increased flow. Larger aquatic insects such as Cranefly Larva, and Golden Stoneflies, can also be stirred up by the higher flows. Other than that, the standard food sources of midges, and small mayfly nymphs are still available to trout.
The Blue River through Silverthorne is holding at about 400 CFS. This can be a prime flow to fish this piece of water. More water makes the trout less spooky, and provides them with ample food. Expect to find fish in shallow calm water along the banks, and in deeper pools and eddies that contain some soft water. Small mayfly nymphs, midges, and Mysis Shrimp are still the staple food sources. Sometimes at these higher flows a small to medium sized Golden Stonefly nymph, or Cranefly Larva can effective as well.
Rumor has it that the stocking truck was just sighted in town.....if you find large numbers of trout holding in the same piece of water these could be recently stocked rainbows which will be willing to eat eggs, worms, and beadhead nymphs untill they get caught enough times to "smarten up". Our report from 4/18, and patterns listed above will still be the recomended set up for targeting resident fish that have not been freshly stocked.
The Blue River in town is fishing consistently, and not much has changed in the typical aquatic food sources available to trout (Mysis Shrimp, Midge Larva, and small Mayfly nymphs are the typical staples). We have been seeing stronger hatches of midges (black/dark grey size 20/22), and a few Blue Wing Olive Mayflies emerging as well. The flow is currently holding near 100 CFS, but should start climbing as warmer spring weather eats away at our snowpack. When the flows do start to rise, expect Mysis Shrimp to be food source number 1 for the trout in town. Finally, we have not had any reports of recent stocking here in town, we will post an update when we do get the word.
Question: What's going on with the Gold Medal status of the Blue River?
Answer: The Blue River between Silverthorne and Green Mountain Reservoir has been delisted from Colorado's Gold Medal list. The Blue within the city limits of Silverthorne is still listed as Gold Medal water. There are still great fish to be caught from Silverthorne all the way to Green Mountain Reservoir (and below). If you check in with us regularly, you have seen hundreds of photos of fish that were caught in this stretch over the years, and many that were caught (and released) this year. It's true; you won't find the numbers of fish north of Silverthorne that you will see in Silverthorne. But you will find fewer anglers and less selective fish!