Local resorts use millions of gallons of water to lay down a good skiing base for the holidays, and while snowmaking efficiency has increased, some environmental concerns remain
By Bob Berwyn
SUMMIT COUNTY — Mother Nature hasn’t been overly generous with snowfall yet, but the four ski areas in Summit County have all been able to open good chunks of terrain largely with the help of snowmaking.
Covering runs with enough snow for skiing and building features in terrain parks requires significant amounts of water. The latest figures compiled by state water officials show that Arapahoe Basin, Copper Mountain, Breckenridge and Keystone have diverted about 1,477 acre feet (481 million gallons) of water from local streams and reservoirs for seasonal snowmaking operations.
With better snowmaking technology, the ski areas have been able to do more with less, especially if temperatures and humidity combine for optimal snowmaking conditions.
This season, all the resorts still have water rights available in their portfolio, even as the end of the snowmaking season nears.
Here’s the breakdown:
– Breckenridge: 670 AF (out of about 800 AF available
– Keystone: 451 AF (out of 1,151 AF available)
– Copper Mountain: 309 AF (out of 517 AF available)
– Arapahoe Basin: 47 AF (out of 299 AF available)
The figures for Keystone, Copper and A-Basin are based on last week’s reports.
For the sake of comparison:
– Frisco well water use, 2005: 792 AF
– Keystone Ranch golf course irrigation: 500 AF
Some ranches in the Lower Blue also use about 500 acre feet of water during the summer irrigation season to water pastures and hay fields.
An acre foot equals about 326,000 gallons of water, generally considered enough to supply an average family for a year.
About 80 percent of the water used for snowmaking returns to the rivers in the spring.
“We’re creating a big white reservoir up on the mountain,” said Blue River water commissioner Scott Hummer, describing how the water used for snowmaking helps sustain spring flows in high country streams.
Each spring, water officials monitor a trail at each of the areas to measure the snowmelt and test the return rate.
The increased snowpack can be a big plus in dry years, preventing some streams from drying up early. But higher runoff volume in some smaller tributaries high on the mountains can also lead to water quality challenges.
Some of the runoff goes through areas that have been heavily graded, where native vegetation has been impacted by ski area operations. Some of the smaller streams simply can’t handle the added volume of runoff, leading to streambank erosion and sediment loading.
None of the areas are required to end snowmaking this time of year, said Joe Foreman, the winter sports administrator for the U.S. Forest Service. In many cases, the scheduling is determined by several factors, including the need to try and open as much terrain as possible for the busy holidays.
Cost is also a factor, said Foreman, who also worked for the private side of the ski industry at Steamboat. Staffing and energy use for snowmaking are both expensive, so the resorts try to stick within their budgets and operating plans, Foreman said.
In past years, the end of December has generally marked the end of snowmaking for many resorts, but Keystone, for example, has continued some limited operations beyond then to help maintain high-traffic areas, Foreman added.
Copper officials said Dec. 24 will be the last day of the season, and Town of Breckenridge officials reported that snowmaking operations and diversions are also winding down at the ski area. The snowguns may be fired up again for a short time in a few weeks to make snow blocks for the annual snow sculpting competition.
All the resorts are required to maintain minimum stream flows downstream of their diversion points. To help meet that requirement, Keystone pumps water out of the Roberts Tunnel, which delivers Dillon Reservoir water to the Front Range.
Breckenridge stores water in Goose Pasture Tarn, and also has a deal with Colorado Springs to tap into water from high in the Blue River Basin. The resort combines those sources to try and maintain minimum stream flows in the Blue River north of town.
Copper diverts water directly out of the Tenmile Creek drainage and is obligated to maintain a 7 cubic foot per second flow at Officers Gulch. Earlier this week, the flow at the gauge was about 26 cfs.
Arapahoe Basin developed its snowmaking system later than the other resorts and committed itself to a higher level of stream protection for the pristine North Fork when it agreed to its permit conditions with the U.S. Forest Service.
In addition to maintaining minimum stream flows, A-Basin is also required to bypass a certain amount of water to protect a brook trout fishery downstream.
State officials toured the ski areas earlier this year to look at the diversions and get a sense of how well the resorts are living up to their requirements. The inspection showed a high level of commitment to good record keeping and to maintaining the minimum flows, Hummer said.
Despite the minimum stream flows, there are still concerns about the overall impacts of massive water diversions in the fall, when rivers are already at their lowest levels. Since there has never been a comprehensive analysis looking at the cumulative impacts, it’s hard to know to what degree snowmaking diversions are affecting aquatic life in the streams.