Battles concerning the harmful results, benefits and economic impacts of these dams have been waged in the media and in the courts. Regardless of the outcome, however, one thing is for sure: many of the tailwaters below the dams that have wriggled through the red-tape wars usually provide the ingredients for year-round, trophy fisheries.

Most of the top tailwaters in the Rocky Mountain states exist on rivers at lower elevations. Before the construction of the concrete plugs, they ran warm and dirty and contained few fish. Frequently, the species consisted of suckers and carp, or perhaps a native, non-sporting fish such as the Colorado River's squawfish or humpback chub. The construction of a dam, though, normally imparts notable changes.

Acting like a catch basin of sorts, the reservoir above a dam traps the majority of silt. With the controlled outflow below the dam coming from the colder depths of the reservoir, the by-product is a cold and clear, moderately flowing tailwater, filled with prime habitat and a good food supply. The trout grow fast, fat and sassy throughout much of the year. and the odds for hooking a big fish are excellent.

A while back, fellow outdoor writer Joe Reynolds and I fished two of the West's prime tailwaters on our way to Salt Lake City. We had only five days to spare, so we knew having someone provide their expert knowledge would be best.

The first stop was Lee's Ferry on the Colorado River in northern Arizona, about 260 miles from Phoenix. David Foster, who basically grew up on the river, served as our guide. His family has lived in the area for years and also owns Marble Canyon Lodge, located only a few miles from the launch ramp.

Created by Lake Powell's Glen Canyon Dam, the tailwater known as Lee's Ferry is essentially 15 miles of big, flowing water with an average temperature between 45 and 50 degrees. Towering sandstone cliffs along the shoreline supply a spectacular setting as the Colorado winds from the dam to the launch ramp. Here, a break in the canyon walls marks the location where John D. Lee once ferried pioneers across the river in the 1870s. A few miles farther downstream, the Colorado river enters the Grand Canyon.

Lee's Ferry has garnered an up-and-down reputation of sorts. The Arizona Game and Fish Department (AGFD) and U.S. Fish and Wildlife Service began stocking rainbow, brook and cutthroat trout in 1964. To supplement the trout's diet, the agencies also added freshwater shrimp

The trout grew rapidly; from 1971 to 1976 the average size doubled to about 3 1/2 pounds. By the late '70s and early '80s, a 10-fish limit frequently weighed 50 pounds, with lunkers over 10 pounds appearing regularly.

Subsequent regional and national publicity attracted fishermen from across the country. Abuses and inadequate enforcement of the regulations eventually took their toll. In 1978, the AGFD reduced the limit from 10 to four. The effect was minimal, though; too many fishermen culled their catches by saving smaller fish until they caught larger replacements. Many of the released trout died.

To stem the decline further, the AGFD put an immediate kill or release rule into effect in 1980, banned the use of bait in 1986, and installed a slot limit of 16 to 22 inches in 1990. The daily creel limit was cut again -- this time from four to two fish. The new rules resulted in less fishing pressure, lower mortality and a noticeable size increases. From 1985 to 1987, the average fish size jumped from 1 1/2 pounds to 2 1/2 pounds.

With flyrods in hand, we began our day by wading a sandbar only a few hundred yards from the dam. Later, we fished a few of the more popular holes along the river. Each one gave up at least a half-dozen fish chunky rainbows. Our top catch came at Nine-Mile (distance from the launch ramp), where we landed more than a dozen fat 'bows. A variety of flies seduced fish, but freshwater shrimp imitations (scuds), Wooly worms and San Juan Worms, a fly made popular on another tailwater fishery in New Mexico, excelled.

I spoke with a couple of fishermen in a bassboat who were using spinning gear about a mile downstream from dam. They, too, caught lots of fish, mostly on silver Z-Rays, Panther Martin spinners and small Dardevles.

Foster claims fishing success depends largely on reading the river. The trout begin spawning around October and sometimes continue through March. They favor places where the water flows gently over a gravel bar, the prime locations for their redds (nests). As the spawn dwindles and the weather warms, the fish move to feeding lies along the main current where they can ambush tasty tidbits as they move downstream. Large boulders, slow-moving riffles and deep holes or back eddies all typify the trout's preferred hangouts.

Two days later, Reynolds and I arrived at the Green River in northeast Utah.

Like Lee's Ferry, the Green took a while to gain a reputation as a notable fishery. At first the stocked trout thrived poorly and showed little growth. Fish biologists finally concluded the water coming from the base of the 700-foot-high dam was much to cold for the trout's well-being. To alleviate the problem they installed a system of baffles. These allowed water releases at a specific temperature from any level of Flaming Gorge Reservoir, resulting in a constant flow of 52 to 53 degrees, the ideal temperature for the rainbows, cutthroats and browns prowling the water. By most estimates, the first seven miles of the Green, between the dam and the first take-out ramp at Little Hole, harbors an astounding 20,000 fish per mile.

Reynolds and I visited the local tackle shop the first night, and found the clear boxes on the shelf crammed with thousands of flies, representing dozens of patterns.

The young lady standing next to the cash register quickly pointed to a tray filled with large, ungainly looking flies when Reynolds asked what the fish were hitting, though. "It's June. Everybody's using cicadas."

We bought two or three styles the girl recommended, went to our room and rigged our fly rods. The next morning, before daylight, we met Brian Barber. Barber works for the U.S. Forest Service and lives in Dutch John, only a few miles from Flaming Gorge Dam. Although he does not guide professionally, he spends many hours floating the Green in his beautiful all-wood Mckenzie drift boat.

The chaos at the launch ramp made it seem like someone was giving away $100 bills. People were everywhere, and a potpourri of floating things from individual float tubes to 10-man inflatable rafts were everywhere in sight. Although most folks were fishermen, quite a few, with no fishing tackle evident, seemed to be embarking on nothing more than a leisurely float down the scenic waterway. A few dozen more wader-clad anglers already had started along the maintained path that hugs the river.

"Typical weekend," Barber quipped with a frown.

Shaking his head from side to side, Reynolds seemed overwhelmed by the number of people on what is supposed to be one of America's premier trout waters. "You mean we can actually catch fish. This is a floating madhouse?"

Barber's scowl turned to a smile. "Yup. And lots of them."

He was indeed right. We hooked our first fish, a fat 16-inch rainbow, about 100 yards downriver from the ramp. The scenario repeated for the rest of the day, all the way our take-out place at Little Hole where Barber's wife met us.

The girl's advice in the tackle shop proved fruitful, too. Live cicadas were evident along our entire float. When one landed on the surface, a hungry trout slurped down the struggling and unfortunate insect within seconds. Our imitation bugs floating high on the surface brought nearly the same reaction. By mid-afternoon we had exhausted our supply of cicada flies. Although we still managed to catch fish on other patterns, the pace slowed considerably. Luckily, a few friends floated by and replenished our supply -- for a fee, naturally.

To say fishing the Green River was unusual would be a glaring understatement. Few places exist where a dry fly garners an immediate strike only seconds after a boat passes over a spot filled with a few dozen feeding trout. It happened to us repeatedly, though. The fish seemingly ignore everything but edible-looking goodies.

Conservatively guessing, I would say the three of us totaled more than 300 strikes each day, with about one-third ending in hookups. We frequently beached the boat, waded a promising-looking area and caught as many or more trout as we did from the boat. One stop produced a rainbow, brown and cutthroat, each over two pounds, within the first 10 few minutes.

Colorado is also home to several popular tailwaters. The South Platte River begins its life in the mountains south of Denver and furnishes good fishing for browns, rainbows and cutthroats along its 70-mile length. Two tailwaters, the Middle Fork below Spinney Mountain Reservoir and the Chessman Canyon section below Chessman Dam, are noteworthy, though.

The Middle Fork's principle residents are wary rainbow trout, while the Chessman tailwater grows jumbo browns and rainbows to 20 inches long. The Colorado Division of Fish and Wildlife has designated the first 20 miles of the South Platte below Chessman Dam as a Gold Medal fishery opened to lure and flies only. Located just a few miles from downtown Denver, this portion of the river is relatively small compared to others in the West. Consequently, the fishing pressure is heavy, especially during the summer months.

The Frying Pan River, flowing from Reudi Reservoir east of Basalt, has retained it reputation as a prime fishin' hole for many years. The dominant species is the rainbow trout, browns and brookies are common and a cutthroat occasionally shows up. Like the lower South Platte, the section immediately below Reudi Dam to its confluence with the Roaring Fork River is Gold Medal water, with catch-and-release in effect for the first two miles. Farther downstream, the creel limit is one fish of each species.

Without question, the "new kid on the block" title as the latest to attract attention as a top tailwater goes to the Dolores River, below McPhee Reservoir in the Cortez area. The dam was completed in the early 1980s. The 12 miles meandering through the wide canyon downstream have quickly earned a reputation as a superb place for catching browns, rainbows and a surprising and unexpected number of cutthroats with dry flies or nymphs. Some of the latter weigh between four and fives pounds.

Both the Colorado Division of Fish and Wildlife and the U.S. Forest Service have managed the Dolores well. The 12-mile stretch from the dam to the Bradfield Bridge is strictly enforced as catch-and-release, lure or fly-only angling. A gravel road runs alongside the stream, so access is easy. Past the bridge, another 21 miles of river, with normal creel limits and the use of bait allowed, also yields good fishing.

The best angling on the Dolores begins after the snowmelt, usually in mid to late June and continues well into the winter months. In fact, if you're into self-punishment, you can experience good fishing in December, January, February and March, when temperatures dip WELL below freezing and snow commonly covers the area around the river.

No wrap-up of tail-race waters would be complete without mentioning two other legendary fisheries. Most prominent in my mind because I have fished it a time or two is New Mexico's San Juan River, 30 miles east of Farmington. The river, flowing from Navajo Lake, remains clear and cold as it winds its through desert-like country.

Access to the best fishing sections is surprisingly easy. A short walk will put you within easy casting distance of dozens of finning trout. Because the water rarely gets deeper than your thighs, wading is a snap.

Strict rules keep the fishing on the San Juan excellent. The first quarter-mile below Navajo Dam is catch-and-release and only artificials or flies with barbless hooks are legal. The next 3 1/2 miles have the same tackle restrictions, but anglers may keep one trout that must be at least 20 inches and killed immediately. Once you kill a legal fish, you must quit fishing.

The San Juan Worm, Wooly Buggers, streamers and any number of drys or nymphs are productive, depending on the hatch and time of the year.

In Montana, the Bighorn has been and still is one of the better tailwaters. This big water comes into its own in April with good nymph fishing. The dry-fly fishing starts getting hot, as midge hatches occur in April, and mayfly hatches pick up in May.

Bighorn trout, mostly rainbows and browns, average 15 to 18 inches, and fish up to six pounds, though not common, do show up occasionally.

Although the rivers goes for 32 miles, the first 13 miles below Afterbay Dam yield the better fishing. Access to this section is available at Afterbay, Lind and BigHorn, and a boat is the ideal means to get to the best fishing.

The Rocky Mountain states have many other good tailwater fisheries. Because many of them fall within trophy fishery designation, they often have restrictive regulations. They might include a reduced limit, slotted size rule or total catch-and-release. In many cases anglers may use only artificial lures and/or flies. So before you visit any of the fisheries, contact the game and fish agency in the appropriate state.

If you have never fished a specific tailwater, you also should check out the more popular ways to fish them. Although wading works for some, a boat, raft or float tube might serve better on others. In either case, first-timers should consider hiring a local guide. Being familiar with the river, a guide will know what type of lure or fly entices fish at a particular time of year, where the fishing is best and any dangers presented by the river.