BOARD02010

• Board Meeting Date: 9/24/2001
• Description: Snowmass Water and Sanitation District 404 Permit
• Board Meetings - Doc Type: Memo

the Caucus and the County withdrew those objections after entering into formal agreements with a
the SWSD. These agreements specified how SWSD would work with the parties to minimize _
impacts on Snowmass Creek by using storage in the Brush Creek watershed and using Brush
Creek water. The County agreement included a 4 cfs by-pass flow that was termed a survival
flow for the trout population (the basis for this 4 cfs flow is unknown), The Corps record on this
project indicates that we issued the permit based on these agreements, and that these agreements
satisfied the concerns of the objectqrs, In 1994, the Corps worked with U.S. Forest Service and
the Aspen Skiing Company on the Snowmass Ski Area Expansion EIS that included a
snowmaking expansion using Snowmass Creek water provided by the SWSD diversion. As a
result ofthat work, the Corps developed a minimum by-pass flow for the diversion water for
snowmaking purposes and modified the SWSD permit to include a condition requiring a
cessation of snowmaking water withdrawals when the creek reached certain limits during a 1 in
10-year low flow event. Snowmaking diversions had to cease when those diversions would
cause stream flows to drop below 8 cfs, The Corps by-pass flow condition currently does not
affect municipal diversions.

During the EIS process, the Aspen Skiing Company petitioned the CWCB to lower the
in-stream flow right held for Snowmass Creek from 12 cfs to 7 cfs for the winter months to allow
for the snowmaking system they wished to employ, The CWCB eventually granted that request
after several hearings and over objections, The Aspen Wilderness Workshop (A WW), one of the
Petitioners, filed a lawsuit against the state for the lowering of the in-stream flow, and after
several appeals, the Colorado Supreme Court ruled in favor of A WW, The CWCB, the Caucus,
A WW, the Colorado Division of Wildlife, and the Aspen Skiing Company entered into
negotiations and with the help of the U.S. Forest Service developed a stair-step minimum flow e
for Snowmass Creek for snowmaking diversions that recognizes the different flow regimes that
occur and sets a varying minimum flow for each of the flow regimes, The CWCB set this stair-
step minimum flow as their in-stream flow water right. Again, the CWCB's in-stream flow only
protects the stream from snowmaking diversions, as the SWSD water right is senior under
Colorado water law, The SWSD can divert water from Snowmass Creek exercising their water
right to divert water until the creek reaches 4 cfs, Which is the unsubstantiated survival flow in
their 1979 Agreement with Pitkin County, .

3. Peti~ion: The petition requests that the Corps1modify the permit to include a condition
requiring the stair-step minimum flow developediby the CWCB, This minimum flow would be
enforced for all diversions of water with the exception of emergency conditions, The Petitioners
cite the appropriate regulations for modifications, 33 CFR 325,7, and provide several reasons
why the Corps should modify the permit to include the state's in-stream flow, The Petitioners
also request that we require the SWSD to install an accurate gage system at the diversion, The
current gage experiences icing problems and we often do not receive accurate readings during
the winter,

First, the Petitioners cite the history ofthe permit process and the fact that the Corps
favorable permit decision relied on the agreements signed between the SWSD and both the
Caucus and the County. The caucus withdrew objections to permit issuance in 1978 and
insistence on by-pass flow conditions in the permit specifically in reliance on the SWSD's a
representations that the fishery in Snowmass Creek would not be affected and that a satisfactory _

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