Nymphing Techinques – the reality is that 80% or more of Bow river fish are caught using some type of nymphing technique.
Hopper/Dropper – use a foam style fly that you can see as your “strike indicator” and add a bead head dropper fly (8” to 24”) below it. This technique is particularly effective when fish are feeding in two feet of water or less (primarily riffles) or along the banks.
Indicator Style – “standard nymphing” choose a style of strike indicator that works for you. Use weighted flies to match the water conditions. Faster, higher water = heavier fly. Lower water conditions = lighter flies. The most important thing is to be within inches of the bottom. If you don’t “snag up” every once in a while you are NOT deep enough. This does mean that you should be adjusting your indicator depending on the water depth you're fishing. A good rule of thumb is 2X the average water depth of the area you are fishing.
Multi Fly Rigs – most of the time we use two or three flies on a standard nymph rig. Casting is not pretty but it allows you to change flies to figure out what the fish are eating. Figure out a multi fly system that works for you (there are many ways to tie it up) and get good at setting it up and how it presents the flies.
Mending – This is important for all techniques but is critical to proper nymphing. Learn how to mend and manage your fly line to get the flies to where they need to be fished.
Use knowledgeable resources. Specialty fly shops have people with many, many years of experience. They are your best resource to help learn what to do. It is challenging, so shorten your learning curve by learning from those willing to share their knowledge.
Good luck on your next Bow River adventure.