As Colorado struggles to figure out how to fill its drought-stricken reservoirs, the once-popular saying "rain follows the plow" may be morphing into "water follows the chain saw." Top state officials have touted increased logging as a way to create more runoff from the high alpine forests that straddle the headwaters of four of the region's major rivers.
Last month, Kent Holsinger, the Colorado Department of Natural Resources assistant director for water, told members of a drought task force that cutting more trees on state and national forests could create up to 500,000 acre-feet of new water. "He proposed it quite seriously," says Peter Binney, director of utilities for the city of Aurora, who also attended the task force meeting.
When the news of Holsinger's proposal - with photos showing the type of logging it would require - hit the front page of the Denver Post, it got people across the West talking. The aerial photos showed demonstration projects in Colorado and Wyoming, where patchwork clear-cuts had been sawed from the forest to boost runoff.
Jeff Kessler of the Laramie, Wyo.-based Biodiversity Conservation Alliance describes the Wyoming demonstration project as "a disaster, a total sacrifice zone."
But as Western water officials and politicians try to wring out every last drop of water for growing cities and parched irrigators, logging for water doesn't sound like such a bad idea to some. "Based on this year's drought, we need to look at all the options," says Blair Jones, press secretary for Rep. Scott McInnis, R-Colo.
There's even some research backing the claim that logging can make forests more water-productive. Chuck Troendle, a retired Forest Service hydrologist who lives in Fort Collins, Colo., studied a 714-acre clear-cut project on a Colorado state forest and a 4,100-acre project in south-central Wyoming's Medicine Bow National Forest.
According to Troendle, falling snow collects on tree branches in dense forests, turns to ice and evaporates into the air. If trees are removed, snow falls to the ground, melts and becomes runoff. But to create any measurable change in the amount of water flowing into streams, he says, you need to cut at least 25 percent of the trees in a watershed. And the extra runoff only happens in the wettest years during the spring, when many reservoirs are already full. As a result, that water would have to be stored behind new or bigger dams to make a difference during dry years.
Researchers also studied clear-cut and thinning projects on over 20 watersheds in Arizona's Coconino National Forest from the late 1950s through the early '80s, says Dan Neary, a Forest Service hydrologist in Flagstaff. Known as the Arizona Watershed Program, the project's goal was to generate more water for the state's growing population. Neary says the studies showed that clear-cuts of just the right size produce more runoff, but that there is only a "finite amount of water you can milk out."
Based on the science, millions of acres of forestland would have to be clear-cut and thinned to produce a half-million acre-feet of extra water, as Colorado's top water official has suggested. "You have to do it over an enormous landscape," says Andy Stahl of Forest Service Employees for Environmental Ethics.
Following the Denver Post expose, Holsinger is no longer talking and the state has backpedaled. "We don't have any plan to clear-cut forests for water yield," says Greg Walcher of the Department of Natural Resources. "Producing water in rivers is not a goal."
But there are other signs that state officials think cutting trees for water has merit. In September, the state appealed the White River National Forest Plan, urging the Forest Service to, among other things, boost commercial logging and manage the forest with an eye toward "restoring water yields." And the Department of Natural Resources Web site features highlights from a legislative tour the agency hosted this fall, touting "the benefits of more active forest management on water yields in Colorado."
Environmentalists say any plan to log for water faces a fight. "No one clear-cuts anymore," says Stahl. "The prospect of increasing more runoff in the spring when nobody needs it isn't going to induce Forest Service managers to take on the public wrath over starting clear-cutting again."
The author is special projects editor for High Country News.
You can contact ...
- Colorado Department of Natural Resources, 303/866-3311;
- Andy Stahl, Forest Service Employees for Environmental Ethics, 541/484-2692;
- Jeff Kessler, Biodiversity Conservation Alliance, 307/742-7978.