The unknown story of the Roaring Fork headwaters
August 26, 2012
ASPEN – Think about the Roaring Fork River in a typical spring, and it conjures images of a majestic, wild river that makes up for its narrowness with a vigorous flow fed by the high country’s melting snow.The Roaring Fork was considerably more tame this year because the snowpack was so sparse and the temperatures warmed so rapidly. But even in a normal year, the Roaring Fork River is a fraction of its natural self. For 77 years a considerable amount of the roar has been taken out of the river by a dam at the confluence with Lost Man Creek and water diversions from the river’s primary tributaries.An impressive-sized dam spans the entire river gorge at that point. The cement wall sends water from the river and Lost Man Creek barreling into a system that eventually empties into Grizzly Reservoir, the next valley to the south.The Basalt-based Roaring Fork Conservancy has educated people about the valley’s namesake watershed since 1996. Education director Tim O’Keefe said most people are shocked to learn the Roaring Fork River isn’t free-flowing.The conservancy estimates that 37 percent of the average flow of the headwaters – as measured just upstream of Aspen – is diverted annually by the Independence Pass Transmountain Diversion System.The conservancy has organized tours of parts of the fascinating water diversion system for the last decade. It’s not trying to fuel controversy that usually dominates debate over diverting Western Slope water to the Eastern Slope, O’Keefe said on a tour Aug. 18 with about 16 curious valley residents. The nonprofit organization is trying to promote understanding.”In Colorado, not all water flows downstream. It goes elsewhere,” O’Keefe said. “We drive up Independence Pass and don’t realize there’s a lot more going on water-wise.” The conservancy realizes the water is put to good use irrigating crops on the Colorado plains east of Pueblo and providing domestic water for Colorado Springs, Pueblo and other areas, O’Keefe said. But the organization is also concerned about maintaining water levels high enough to keep river and stream ecosystems healthy year-round.”The choices we have to make are tough,” O’Keefe said.
Regardless of philosophical leanings, observers tend to acknowledge the Independence Pass Transmountain Diversion System is a remarkable feat of plumbing.All told, the system collects water from 45 square miles in the Roaring Fork watershed, all above 10,600 feet in elevation. Water from 19.25 square miles is collected from Lost Man Creek and the Roaring Fork River above the confluence with Lost Man. That accounts for about 43 percent of the diversion system.Water is collected in Lost Man Reservoir, about one-quarter mile away from the lower Lost Man Trailhead, and channeled through a canal and culvert that runs beneath Highway 82 and spits the water out in the river just above the dam. The dam itself is about one-half mile from the highway. The cement wall diverts water to the south, into a two-mile long tunnel that empties into the Lincoln Creek Connection Canal. That cement lined canal, high above the road in majestic Lincoln Gulch, spills into Grizzly Reservoir.Across the gulch, on the steep north-facing mountainsides, is the underground New York Collection Canal, which diverts water from New York, Brooklyn and Tabor creeks. That diversion taps 10.5 square miles and accounts for 23 percent of the system.In addition to receiving water from the diversions north and south, Grizzly Reservoir collects water from upper Lincoln Creek and Grizzly Creek. Those two creeks tap 15.25 square miles of watershed and account for 34 percent of the diversion system.
The legal rights to the headwaters were apparently never claimed for silver mining or ranching back when Aspen boomed in the 1880s and ’90s, or the rights were abandoned.They were claimed instead by farmers east of Pueblo plotting since the 1890s how to properly irrigate 56,000 acres of prime farm land in southeastern Colorado. They acquired water from Twin Lakes Reservoir but it wasn’t enough to grow their crops. In 1930 they took steps to tap the Roaring Fork River’s headwaters. Construction of the system was completed in 1936.The marvel of the system – and the eye-popping highlight of the conservancy-sponsored tours – is the nearly 4-mile long tunnel from that starts at Grizzly Reservoir, burrows beneath the Continental Divide and releases on Lake Creek, 12 miles above Twin Lakes Reservoir. Once released, the water is delivered to the water rights holders via the creek, reservoir and Arkansas River.The Independence Pass Transmountain Water Diversion System is operated by the Twin Lakes Reservoir & Canal Co., whose primarily share holders are Colorado Springs, with 55 percent, and Pueblo utilities.The maximum volume the system can divert annually is 68,000 acre feet, said Scott Campbell, general manager Twin Lakes Reservoir & Canal Co. In any given 10-year period, the volumetric limitation is 570,000 acre feet, he said.Campbell said possibly the greatest legacy of the Independence Pass system is what was accomplished by the construction crews. Crews started on the east and west ends in November 1933 and completed the structure in 408 working days. It has 51 feet of fall from west to east.The tunnel entrance from Grizzly Reservoir is disguised as a garage from the outside and looks like an old silver mine entrance in the inside, with the cribbing still intact. After walking downhill about 30 yards into the cool shaft, the water diversion takes a straight shot to the East Slope. The tunnel is essentially a round cement culvert, about nine feet in diameter. While standing in it, viewers can see a pin prick of light – a real light at the end of the tunnel.The other wonder of the diversion system, Campbell said, is it delivers headwaters from the Roaring Fork to melon fields 220 miles away.”I would guess if we were building this today it would cost more than $1 billion,” he said.
The diversion system is dependent on snowpack. In 2011, when winter wouldn’t end and the snowpack kept building into April, the entire 68,000 acre feet was diverted, Campbell said.To put that in perspective, that amount is about 65 percent of what Ruedi Reservoir holds when full.In this drought year, just less than 25,000 acre feet has been diverted, according to Campbell. That is 37.5 percent below the average diverted during the 77-year life of the project, he said. The average is 40,000 acre feet.”What we’ve seen the last two years is the opposite end of the spectrum,” he said.In wet and wild 2011, Campbell’s office fielded calls from officials in the Aspen area asking if the system could divert more water and ease the flooding risk along the Roaring Fork River. The system had diverted its limit while runoff was still high and there was uncertainty about how it would affect the valley. Campbell said his outfit would have certainly be “neighborly” and take more water, if it could be done legally. Legalities prevented it from offering much help.On dry years like this, water diversions are considered unfortunate by conservationists and outright villainous by some observers. The Roaring Fork River ran dry below the dam at the Lost Man confluence on some days during diversions, O’Keefe said. Roaring Fork Conservancy and other organizations want minimum instream flows for the river and its tributaries. Twin Lakes Reservoir & Canal Co. is entitled to its water, up to the 68,000 acre feet limit, and doesn’t have to maintain instream flows. (It regularly works with other water managers on a “transfer” program, through which water is kept in the Roaring Fork and Twin Lakes Reservoir & Canal Co.’s right is fulfilled with substitute water from the Eastern Slope.)The system hasn’t diverted during the dry conditions of August. Even so, the Roaring Fork barely even purrs at the headwaters, let alone roars. Only about 14 cubic feet per second trickles down toward Aspen from behind the Lost Man dam.O’Keefe doesn’t see any villain in the story about the diversion system. “The take-home message from all of this is when there’s enough snow there’s enough water for all of us,” he firstname.lastname@example.org