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Four Mile Creek Fishing Information
Upper Section - near Boulder, CO
Four mile creek is a part of the Boulder Creek watershed and is a small, often overlooked creek. Â While the river struggles with consistent flows and difficult access, it maintains a healthy population of brown trout and brook trout.
Up by the Peak to Peak Highway, you can access the river via a few forest roads. Â This is a small creek up there and quarters are tight and fish are plentiful. Â You can get some solitude up on this creek if you make the hike and though the fish are small, the adventure is great and it’s close to town giving you more time on the river.
In the lower reaches up boulder creek canyon, there are eager browns when the flows are up enough. Â As the flows get low you need to bring your “A” game for fishing to spooky trout.
Fish: Some Small-Sized Fish
Popularity: Low
Difficulty: Medium
Accessibility: Medium
Best Techniques: Dries
Best Seasons: Spring - Fall
River Type: Small Freestone
Fish Types: Brown Trout, Brook Trout
Dog Friendly: Yes but Leashed
Located in the South Platte River Basin near Boulder, CO
Fishable Seasons & Current Weather
The best seasons to fish this river are Spring - Fall. See the current weather reports for the next 5-6 days listed below for the nearest city.
Knowing what flies to use is only have the battle. You have to know when the insects are active on the water and when it's likely the trout are feeding on them. Refer to our hatch charts below to understand when the insect categories and some of the possible hatches on the river.
Midge Hatches
Midges hatch year round, but their importance is from September through winter into April. During the warmer months, the trout often focus on larger insects as they are more active on the water like mayflies, caddis and stoneflies.
Aside from Blue wing olives, mayflies are active most commonly from May to August in Colorado. There are many different mayfly hatches found on most rivers and the most common are listed below.
Blue Wing Olive: September throut winter to April
Colors: Green/Olive
Sizes: #16-24
Pale Morning Dun: June to Mid September
Colors: White, Yellow
Sizes: #14 - #20
Caddis Hatches
Caddis hatch starting early in May and continue to the end of October.
Colors: Olive, Green, Yellow, Tan, Orange, Brown and Black.
Sizes: #10 - #20
Stonefly Hatches
We have some great stonefly hatches in Colorado and while not all rivers carry all species of salmonflies, you can often fish stonefly adult patterns with confidence from May to September. Start off in bigger sizes and get smaller till September hits (size 8 - 16)
Yellow Sally Stonefly: Mid June to August
Colors: Yellow, Tan
Sizes: #12 - #18
Terrestrial Activity
Terrestrials don't hatch since they are out of the water, but they can have importance starting in Mid April and ending in September.
These are the the top flies we sell for this river. Use the hatch chart above to know what flies you will want to have in your fly box during your adventure on the river and then select the flies here 30 days before your trip to get them at a great price. All of our flies are hand tied to each order to ensure quality and to keep our prices low for you.
Click on a fly below to select a size and color for purchase.
Our fly assortments make fly selection easy. We take our entomology knowledge and years of fly fishing experience on these rivers to bring you the right fly patterns, including the correct colors, sizes and quantities to set you up for success. A good selection of flies will prepare you properly for anything the trout may be eating on the river and our fly assortments are specifically curated to maximize your success. Take a look at the assortments we provide below and add one to your box today. Use coupon code AST50 for $50 off and free shipping on these as well, just to help make fly fishing a little more affordable!
Click on any of the pictures to see what flies, colors and sizes we recommend in each assortment.
View our access map for the Four Mile Creek and learn public and private access points as well as other notable features around fly fishing this river. We include headwater and confluence data and in an effort to not "hotspot" river access points that are better than others, we list every access point available. This serves two purposes. First, it keeps us from hotspotting, which is just showing the best spots and bringing unwanted and harmful attention to the specific access point. The second reason is while we want to help you catch fish and find great places to explore, we don't want to spell it all out for you. If you get it all spelled out, we're doing the exploring, not you. Missing out on the journey of exploring places to fly fish is one of the more enjoyable aspects of fly fishing. While not everyone has time to go explore everything in person, we provide some of the top level data to help you know if something is worth your time, then pass it off to you to explore and find your own adventure. Now enjoy the info, if you're on this page then this river is worth exploring! Go out and find some memories.
Four Mile Creek Tips & Resources
Use these epic resources to get ready for your adventure. Whether you're planning your trip, learning your insects, improving your fishing with expert tips or getting detailed resources from the USGS streamflows or DoW, we got you covered to help you find the river and find the success you want.
