“Be careful of rattlesnakes,” Brian Werner says as we walk near what will, a few years out, become the south end of Chimney Hollow Reservoir. I try to imagine what will happen to the snakes—and the bears and birds and burrowing animals—when these 1,600 acres become a lakebed. I’d been conducting an animated interview with Werner for more than an hour as we toured the region’s waterworks–reservoirs, pipelines, diversion ditches, pumps—but now, standing here, I’m speechless. Perhaps sensing my mood, Werner tries to be upbeat. He gestures to the west, where, as part of the reservoir land-acquisition deal, another 1,800 acres will be permanently protected. But it’s hard to stand beneath those ponderosas and not feel a kind of heartbreak.
Werner works for Northern Water, a public utility that delivers water to parts of eight northeastern Colorado counties and about 880,000 people. In conjunction with the U.S. Bureau of Reclamation, Northern Water administers the Colorado-Big Thompson Project, a sprawling collection of reservoirs and pipes built to send Colorado River water from the western part of the state across the Rockies (through a tunnel beneath Rocky Mountain National Park) the more populous—and growing—northeastern towns. Werner’s job title is public information officer, but after 34 years with the utility, he’s also its de facto historian, with an insider’s deep knowledge of the entire state’s water past and present, including the intricacies of water rights. (Western water law is an unfathomably complex beast predicated on a first-come-first-served system, which is why newer cities, late to the game, are struggling for rights to water that often flows right past them.)
Up and down Colorado’s Front Range—the string of cities perched along the Rocky Mountains’ eastern flanks—it’s a boom time. Fort Collins, the northernmost city, has doubled its population since the 1980s, with no sign of stopping. Farther to the east, in former rural communities like Frederick, Dacono, and Evans, pavement is spreading like weeds, subdivisions are sprouting in place of corn. The reservoir soon to drown the spectacular landscape under my feet that afternoon would deliver water to these bustling communities.
Nearby, another proposed reservoir would submerge a highway to store water from the Poudre River, which flows through downtown Fort Collins; this project will serve those same growing towns. “Some people think if we don’t build those projects, people just won’t come,” Werner says. “I wish that were the case. But it’s not gonna happen. People are going to keep moving here, because it’s a great place to live.”
Across much of the West, the story is similar. As cities and states grapple with urban growth alongside the impacts of global warming—crippling drought, a shifted timeline of snowmelt and stream flows, uncertainty about future water supplies—nothing is off the table when it comes to securing access to water. These days, the stories that make national news are more likely to be about old dams coming down than about new ones rising. That’s partly because dams coming down are still a rarity. But across the West, the local news is far more likely to be about smaller dams going up. The era of water mega-projects may be behind us, but engineers are still transforming landscapes to deliver water—an increasingly elusive and valuable commodity…
“The Reclamation era”—roughly the 1930s to the 1970s—“was big monster projects, massive dams that totally reshaped the watershed, rivers, and ecology,” says Reagan Waskom, director of the Colorado Water Institute at Colorado State University in Fort Collins. Today’s projects, Waskom says, are a series of “expansions and enlargements,” smaller-scale efforts meant to complement or shore up existing systems…
A subsidiary of Northern Water, called the Municipal Subdistrict, runs the Windy Gap project, which was built in the early 1980s to provide water for Boulder, Fort Collins, and four other Front Range cities. The system pulls water from the Colorado River and stores it in the Windy Gap reservoir on the west side of the Rockies then delivers it to Lake Granby, where it is pumped through the Big Thompson system to the eastern side. But in wet years, Lake Granby, the main reservoir for that Big Thompson system, is already full—leaving no room to store the Windy Gap water. That means in dry years, when the customers really need it, the water isn’t there.
Chimney Hollow is the solution, a way to stabilize the Windy Gap water supply. Water managers call it “firming.” Imagine that you are technically entitled to ten units of water out of a reservoir that stores 100 units. But in a dry year, the reservoir might only contain 30 units, and there are other customers besides you. In such a system, you couldn’t really depend on the reservoir for your water. That worst-case scenario is what water people call “firm yield.”
On the Windy Gap system, the firm yield is currently zero. “In the dry years, there’s no water available,” explains Werner, “and in the wet years, there’s nowhere to put it. You can’t rely on a project with zero firm yield.” Chimney Hollow, the utility contends, will give customers—the city of Erie, say— guaranteed annual delivery of their legally allotted water.
“Even with climate change, we know that there will be high flow years,” Waskom says. “When those come along, you’ve either got a place to store that water or you don’t.”[…]
There’s also the issue of whether there will continue to be enough water in the rivers to make these efforts worthwhile. “Whether you have a big reservoir or just a straw where you’re sucking water out of the river and sending it somewhere else, the question is, will the water be there?” says Jeff Lukas, a researcher with the Western Water Assessment, a think tank based at the University of Colorado. “Just because you’ve done the modeling and your scheme would’ve worked under the hydrology of last 50 years doesn’t mean it’ll work in the next 50 years.”[…]
The new world is nothing if not complex. It’s a world of tradeoffs, a world without easy answers. Still, standing on the hillside at Chimney Hollow, I’m sure of one thing: I wish there was some way to spare this spectacular place.