THE AUTHOR ARGUES THAT SINCE FISH GOTTA SWIM, THIS DAM CAN BE DAMNED

Early one morning last May, two friends and I drove an hour north and a bit west of Colorado Springs to the South Platte River, where it spills out of the front range of the Rockies. We parked the truck, hoisted packs on our backs and, using our aluminum fly rod cases as hiking staffs, climbed up and over the Gill Trail into Cheesman Canyon. There we strung the rods, pulled on boots and vests and started fishing. Two hours later, when we had to leave, we had caught and released 23 trout between us, not one of them less than a pound and several in excess of three.

Two memories of the morning remain fixed in my mind. One is of my friend Bob Condron, a U.S. Olympic Committee official, standing on a rock as he drifted a nymph down a deep tongue of blue-green, racing water and caught eight trout on eight successive casts. "I can't believe it," he yelled across the roar of the water.

The other is of a giant trout holding in about two feet of current just next to my feet. I dropped a tiny bright nymph called a brassie down to him. Three times he ignored it. As it approached on the fourth drift, he lit up and the red stripe down his side pulsed like neon. His body quivered, his tail pumped and he surged forward to meet the fly. And kept on going. I felt him on the line for maybe two heartbeats. Then he was gone.

"I'll bet he went four pounds," said Roger Hill, watching. "That's how it is here."

But it won't be for long. Not if the Denver Water Board has its way.

The board, in concert with more than 40 suburban and outlying communities, plans to build a high dam at a place called Two Forks, about 30 miles downstream from where we were fishing. The dam will impound 1.1 million acre-feet of water—enough, the board says, to supply the needs of the Denver area well into the next century.

Denver and Colorado Springs, which lie within an hour's drive of the South Platte's best trout water, underwent terrific growth in the past decade and a half. There are about two million people in the region, and the pro-dam argument supposes that the rate of growth will remain the same in the years to come. So the great trout fishery of the South Platte will have to go—drowned under a huge, dead lake that will lap nearly to the foot of Cheesman Dam, below which we were fishing.

"But that growth can't possibly continue," argues Hill, a Colorado Springs real estate broker who, despite his stake in Denver's future development, strongly opposes the dam. The recent population surge was due to the oil shortages of the 1970s and the consequent expansion of energy exploration in the surrounding country. "And even if we continue to expand at that pace, there are other, less destructive ways of increasing the water supply," he says. Some have suggested smaller dams or even a water pipeline down from the northern mountains of Colorado, which would still be cheaper than the estimated half-billion dollar cost of Two Forks.

No price tag can be placed on a resource as rich and conveniently located as the South Platte. Biologists have called it the most productive trout river in Colorado—even more fecund than the once-bounteous Frying Pan and Gunnison rivers, which now have dams that have submerged their best trout stretches. Indeed, the South Platte itself has four already-existing dams—Cheesman, Eleven-Mile, Antero and the recently built Spinney Mountain Dam, completed in 1981. But it seems they're not enough. After all, there are lawns to be watered, dishes to be washed, toilets to be flushed—and plenty of trout in other streams....

Not long after my visit to the South Platte, Curt Gowdy arrived on the scene and spoke out against the dam. "I know what dams do," he said. "They destroy rivers. With the exception of the Bow River through Calgary, this is the finest trout stream close to a major city on the entire continent. We had a slogan for the American League of Anglers which said, 'Fish don't vote, but fishermen do.' If we squawk enough, if we band together, we can get so much done."

The U.S. Army Corps of Engineers is presently completing a $36 million study of the environmental impact of the project and should make its preliminary report by year's end. That report will be followed by a 90-day period of public debate. It is time to stop fishing and start squawking.