To say the Potomac River is a big river, is an understatement worthy of a colonial tar and feathering. The Potomac - 405 miles in length, 4th largest river on the Atlantic Coast, and 21st overall largest river system in United States - differs incredibly depending on when and where you are fishing it.
In some places it is as pure and breathtaking a waterway you will ever find, in others - it'd be wise to wear a hazmat suit when netting your catch. But that's the beauty of urban fishing. You've got to fish where you are.
The North Branch and South Branches of the river are a renown trophy trout water - boasting great numbers and size within their rainbow, brown, cutthroat, brook, and golden trout populations - until it reaches the salt line near the Piedmont Plataea on it's drift down the Atlantic Coastal Plain. In laymen's terms, the river shifts from a trout water to a smallmouth fishery before ultimately becoming a truly tidal fishery with elements of both salt and freshwater fly fishing once it reaches our beloved District.
Because of the incoming salinity from the Chesapeake Bay, the Potomac plays host to prominent runs of anadromous fishes (fish that live in salt and spawn in freshwater) in the spring - i.e. White Perch, American Shad, Hickory Shad, and Striped Bass - while also harboring mostly freshwater tolerant species such as Large & Smallmouth bass, Gar, Blue Gill, Sunfish, Crappie, Catfish, Carp, and invasive species such as Northern Snakehead and common Gold Fish. Needless to say, you never know what is on the end of your line.
The Potomac's combination of size and mixed bag potential reinforces the importance of treating the river like a saltwater fishery. Similar to the legion of tournament bass fishermen who fish this tidal section of river who cover water by making long casts with spinner and crank baits, covering lots of water with streamers and clouser minnows to find actively feeding fish is the name of the game. Sure you can focus on smaller areas and specific fish (such as mudding carp or spawning largemouth bed), but to truly take advantage of this river's awesome fishery (large, urban game fish) - you got to strip for it.
Outside of flies and stripping speed, depth becomes an important factor as well. Using sinking or intermediate lines to get your flies down in the water column is especially key when fishing places such as Chain Bridge and the Upper Potomac, where turbulent flows keep flies up in the water column and subsequently - away from fish. Even at more urban fisheries such as Gravelly Point or the water discharge at Four Mile Run - getting your fly down in the current and to the fish is as important as fly selection itself. If you're in a rut, experiment with depth more than fly selection to find feeding fish. You've got to find them before you can catch them.
Last cast: The Potomac can be a frustrating fishery. Its muddy waters and urban fish often giving the fin to those in pursuits of its natural treasures. But by thinking outside of the box and combining fresh and saltwater tactics to find feeding fish, one can improve their hookups exponentially. By following these guidelines to A) throw bait fish imitations , B) cover more water, and C) experiment with depth over fly selection - you will find yourself making the necessary adjustments on the water that you need to BY YOURSELF and ultimately - catching more fish. There is something beautiful in that.
Dig our strange.