April 05, 2019
By Cal Kellogg
When many anglers think about trout fishing, they visualize mountain streams, lakes and reservoirs — the types of waters most often associated with trout fishing and most often fished by trout anglers.
But some of the most productive trout waters an angler could be missing are tailwaters where clear, cold water pours year ‘round from beneath typically large dams. The scenario is often perfect for growing big numbers of big trout.
But not all tailwaters are created equally. The size/depth of the reservoir dictates its ability (how much) to store cold water. Larger and deeper usually means greater reserves of cold water for long periods of the year (if not year ‘round), and the temperature of water released from lakes like these varies little throughout the year. Certainly, it is colder than nearby freestone streams in summer, and it is commonly warmer than freestone streams in winter. In both cases, local trout fishermen find many tailwater temperatures render these fisheries fishable year ‘round.
But the cold-water storage behind the dams of smaller and less deep reservoirs, in some instances, might not be great enough to sustain year-round releases of water cold enough to support a healthy tailwater trout fishery 12 months of the year. These fisheries are often supported during the cold-water months with stocked trout, and holdover trout — oftentimes, the largest trout in tailwater fisheries — may be few and far between.
The “soup” of nutrients that suspend in the reservoir’s water column behind the dam also dictates the quality of a tailwater fishery that varies with the soil type, vegetation and land-use practices in the lake’s watershed.
This fertility factor directly impacts the quality of life for trout forage — aquatic insects, invertebrates and small fish — in a tailwater that rely upon suspended algae and planktons for growth and survival. Typically, it’s all good, but some tailwaters are inherently more fertile than others.
Finally, the process of releasing water (in some instances, pushing the water) through a dam’s hydro-electric facility commonly hyper-oxygenates the water, a boon for both forage and trout in a tailwater.
It stands to reason, really, that where fertile, cold and well-oxygenated water flows through a trout population, the fish are healthy and strong. In fact, tailwater anglers may find the local trout fishing to be some of the best trout fishing in the region for both numbers of trout and trophy trout, like the California state-record rainbow trout caught in 2005 by Frank Palmer. His 27-pound ‘bow was caught in the tailwater of Folsom Dam/Folsom Lake (the American River), a short drive from the state-capital building in Sacramento.
At many dams it isn’t just cold water that flows into its tailwater. Baitfish, such as pond smelt and shad, can be pulled through dams. Some of these baitfish are killed and chopped up in the turbines of the local hydro-electric facility, while others emerge below the dams alive but stunned and confused. These baitfish provide a buffet for tailwater trout, but large and often strong-flowing tailwaters might only be accessible by boat. Put a boat on a tailwater, and you’ve opened the door to back-trolling for trout.
Boat styles are many — from flat-bottomed prams with small outboards, motorized McKenzie-styled drift boats, deep-V motorboats and jet boats — and consideration must be given to match boat/motor performance and boating safety requirements with the condition and character of the tailwater.
You’ll likely be dealing with strong currents, and your boat must feature a reliable motor that has the power to deal with the current. It’s goes without saying, too, that the heavy flows of a tailwater call for the wearing of a proper PFD the entire time you’re on the water.
Traditionally, back-trolling is done from powered boats, but a small, pedal-powered kayak can give the modern kayak angler an opportunity to put back-trolling to work on tailwaters too small for a powered boat. With tailwater characteristics similar to larger rivers, many of these spots can hold trophy-sized trout that have never seen a lure or bait.
In its basic form, traditional trolling is dragging a lure through the still waters of a lake or reservoir behind a slow-moving boat. The pressure of the still water against the slow-moving lure creates the lure’s action.
Back-trolling relies on a river’s current to give the lure its action. When back-trolling, the motor of the boat is used to keep the boat stationary or slowly moving backward downstream at a rate slower than the flow of the water. Lures are trailed some distance behind the boat, and the pressure of the flowing water pushing past the slower moving lure creates the lure’s action. With a skilled hand on the motor, back-trolling precisely steers lures and other offerings into trout hotspots for extended periods of time. When trolling traditionally, the lure or offering passes the fish that either strikes or does not.
Picture yourself on the bank of a trout stream. You’ve got a spinning rod rigged with a spinner. You toss it across the current, close the reel and allow it to swing across the current on a tight line. This is a standard presentation for any stream angler. And when faced with deep water, spin-tackle trout anglers often add split shot to the line to help get the rig down to the trout.
The same is true for the back-troller who works a tailwater trout fishery. When the water isn’t too deep, crankbaits or inline spinners can be worked behind the boat with no additional weight. But when the water is deep, many back-trollers turn to a three-way swivel, the heart of the three-way rig. To set it up, attach the mainline to one eye of the swivel. On a second eye, tie a short 3- to 10-inch dropper of strong monofilament tipped with a snap swivel for attaching the weight. On the third eye, tie 36 to 48 inches of fluorocarbon leader and tip it with the offering of your choice.
Rods can easily be positioned in rod holders when back-trolling at shallow depths, but anglers should hold a back-trolling rod when weighted for gaining depth in the river.
Use a controlled free-spool to get the sinker to the bottom. Close the spool; then, constantly lift and lower the sinker, allowing the weight to “walk” downstream along the bottom in the strike zone, while minimizing snagging the rig on a rocky river bottom.
TACKLE THE TAILWATER
In terms of rods and reels, choose a fast-action rod capable of handling the weight of a rig. Consider, too, the river current but keep in mind a good boat operator will minimize the drag placed on any lure or bait. Traditional bait-casting reels, preferably with an integrated line counter, match nicely with back-trolling rods. Some anglers still use monofilament lines for this work, but many have transitioned to 20- or 30-pound braided line for the main line.
Lure selection for back-trolling is simple. Traditional inline spinners work well, as do spinners snelled onto a length of monofilament. Small to medium-sized crankbaits and minnow-imitating plugs are the most popular offerings, and most any diving crankbait can work down to about 8 feet without tying it to a weighted three-way rig. Streamer fly patterns and soft-plastic grubs in 2- to 3-inch models can produce big numbers of trout and are often overlooked by the back-trolling community.
Back-trollers who prefer baits commonly choose cured roe, live and dead minnows and night crawlers on a three-way rig. Others remove the hooks from a crankbait, attach a short 12- to 18-inch leader to the back hook ring, and finish it with a bait hook armed with a small hunk of cured roe or a threaded night crawler. Rigged this way, the diving ability of the crankbait gets the bait down, and the action of the lure catches the attention of the trout. The next thing you know, a trout has gobbled down that succulent natural bait, and it’s … fish on!