How to Find a Trout Stream


To diehard trout addicts, an excellent blue line is better than a vein of gold. “Blue line” refers to the standard way a topographical map shows a stream. A thin blue line wandering down the mountainside provides the promise of wary brook or brown trout sheltered in the nooks and crannies of small plunge pools.

While anyone can grab a map, how do you know whether the steam will be significant and vibrant enough to be worth the drive and associated hike. Hike? Yes. Most wild streams do not run along the side of the road. Fishing wild water requires some level of physical fitness and the investment of sweat, the ultimate and handy filter to pressure. Randomly following any ribbon of water up the mountainside will undoubtedly give you a good workout, but no guarantee of anything more. Therefore, to increase the probability of success, apply some simple rules to identify the best blue lines.

Fishing wild water requires some level of physical fitness and the investment of sweat.

First, get a topographical map. You need a topographical map for two reasons: (1) To identify the boundaries of the public property; (2) To place the targeted stream in the context of the surrounding terrain. The US Geological Survey provides free PDF format topographical map sheets for instant download in 7.5, 15 and 30-minute sizes.  Chances are the downloaded map sheets will not be scanned in perfect alignment (north vertical) and, since nothing ends up being easy, the stream will invariably span two map sheets; requiring some tricky cut/paste to line everything up. 

Once you have your map, follow these rules to analyze the terrain.

Rule 1: Look for a waterfall.

Waterfalls are usually not marked on the map unless they are prominent. In the example, this stream has two waterfalls indicating robust flow and promising water. There is often a good, deep fishable pool at the base of every waterfall.

Rule 2: Avoid intermittent streams

An intermittent stream does not have full-time water. Trout need constant flow to survive year round. There may be a few trout surviving in random deep community pools, but a full-time stream is always a better choice.

Steep terrain creates pocket water. As water tumbles down a steep slope, it pools in dips and hollows, creating holding positions. The same amount of water on a gentle slope typically indicates a shallow creek. 

Rule 4: Look for multiple tributaries.

This rule is the opposite of avoiding intermittent streams. Find a blue line being fed by other blue lines. The larger the main stream, the better the possibility of year-round trout survival. Also, some tributaries may be fishable streams as well; allowing you to use one hike to fish a variety of water.

Rule 5: Look for a blue line without a nearby trail or a hard hike.

Once you find a good, steady stream, look for the places where the trail veers away or, even better, no trail at all. The harder the stream is to reach, the fewer people will visit. If there is a trail, assess the difficulty of the hike to reach the stream. Fishing pressure is directly proportional to the challenge. A hard hike always translates to low pressure.

Once you decide to visit a good looking blue line, be sure to let people know where you are going and when you will return. GPS-based satellite emergency beacons like the Spot Messenger are cheap and should standard equipment for anyone who ventures off the beaten track – especially trout hikers who will climb over dangerous, slippery rocks on steep hillsides.

With an understanding of how to find wild water, you are no longer hostage to the stocking truck and the crowds clustered on the banks of the well-known streams. Create a command center, identify and analyze water, slap on a day pack and head out into the woods!

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