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• Board Meeting Date: 5/21/2008
• Description: ISF Section - Injury with Mitigation - Case No. 5-07CW210; Application of Vail Associates, Inc. and the U.S. Forest Service
• Board Meetings - Doc Type: Memo

Linda J. Bassi
April 29, 2008
Page 10
VA, in consultation with the U.S. Forest Service, investigated a variety of alternative to
providing a viable water supply for the proposed snowmaking activities near the base
areas of Chairs 36 and 37. These additional alternatives included the following:
0 VA investigated the feasibility of extending a pipeline from the existing
snowmaking water distribution system, which utilizes water diverted from Gore
Creek above the confluence of Red Sandstone Creek and from the Eagle River
at the mouth of Gore Creek. The existing snowmaking system only covers areas
on the front north facing) side of Vail Mountain. This option would require the
installation of about 14,000 linearfeet of air and water pipelines running up
Ramshorn trail from a location near Eagle's Nest to the first ridge and down to
the base of Chair Lifts 36 and 37 via Sleepytime and Tea Cup Bowl. An
additional pump station would also be required. The estimated cost of this
alternative was $2.6 million, not including the costs associated with
environmental permitting. Water supply pipelines on Vail Mountain must be
buried to a depth of 7 feet to prevent freezing, which, for 14,000 feet of pipeline,
would result in the disturbance of about 10 acres of land on relatively steep
slopes. Due to the high cost and issues associated with permitting and
environmental concerns, this alternative was found not feasible.
~ VA investigated the feasibility of installing a surface water diversion on Two Elk
Creek with (orwithout) a water storage tank. Under this option, water would be
diverted from the creek directly to the snowmaking system or pumped into a
storage tank, which would serve to buffer the impact of the snowmaking
diversions on Two Elk Creek. Construction of a diversion structure on Two Elk
Creek at the base of the Tea Cup Bowl would result in impacts to undisturbed
wetlands and riparian areas that provide important aquatic and wildlife habitat. In
addition, a surface water diversion would be difficult to operate and maintain due
to the extreme weather conditions that occur in this area. Due to concerns about
reliability, operational and maintenance requirements, and potential
environmental impacts, this alternative was found not feasible.
It is also important to note that VA investigated the availability of high efficiency
snowmaking guns and selected equipment that can produce snow effectively with a 15
gpm flow. Based upon this evaluation of alternative water sources for snowmaking
around the base areas for Chairs 36 and 37, it was determined that an alluvial well,
tributary to Two Elk Creek ,would be the most reliable and environmentally sound option.
The use of an alluvial well, operated with alternative pumping and recovery periods,
would effectively bufferthe impactof well pumping on streamflows, reducing streamflow
depletions to no more than about 57% of the actual pumping rate.
AMEC Earth and Environmental, Inc.