ATTACHMENT A
Alternative Short Term and Long Term Water Supply Alternatives and Associated
Augmentation Requirements
The following is a description of various alternatives contained in the 1990 Water Management
Program (WMP) along with a description of how supplemental water supplies acquired form
Ruedi Reservoir could be utilized to make these projects operate with fewer water restrictions
including potential "calls" from downstream users which would otherwise limit the effectiveness
for these projects to increase physical water available for use in Aspen's water system. Funding
for short term projects is contained in the Asset Management Plan and some of these projects are
currently in development or construction. Longer term projects have no current funding and
generally would be necessary only to the extent that climate change contributes to a shift in
runoff patterns (earlier runoff) which would have the effect of decreasing the available supply
from existing water sources. The actual need for these long term projects is unknown and the
simpler, less costly alternatives would be employed first to avoid more capital intensive projects
such as raw water reservoir storage.
Short Term Alternatives
Cumulatively the estimated water requirement for short term water projects is approximately 40
acre feet per year (in addition to the water already acquired under a recent contract and described
below). A description of how this water would be used is provided below.
Completion of Reuse System for Aspen Golf Course and Highway 82 Irrigation
This project is currently under construction and development. Water from the Aspen
Consolidated Sanitation District will be pumped to the existing reuse pond (located at the Aspen
Golf Course) and used to irrigate the course along with landscape irrigation uses along Highway
82 (west of Maroon Creek to the airport) and for the Burlingame development and parkland in
this vicinity. Augmentation water form Ruedi is needed to allow this diversion to stay in priority
when downstream users in the Grand Valley have a higher priority than the junior right for the
reuse system. Approximately 30 acre feet per year is the estimated need and these rights have
already been secured for water from Ruedi under a contract with the Colorado River Water
Conservation District.
Completion of Miscellaneous Ponds on City Open Space and Parklands
The City is developing ponds for aesthetic and wetland restoration at a variety of different
locations on City parks and open space lands, as well as, at the Golf Course. Similarly ponds are
under construction to provide for treatment of storm water and through use of wetlands (Jenny
Adair and Rio Grande parks). The evaporation from these ponds requires augmentation from
supplemental sources when downstream rights experience water shortage conditions.
Long Term Water Supply Alternatives
Long term water supply alternatives are described in the existing WMP in priority of
implementation. According to that document, the lowest priority project is development of
surface water storage on Castle and Maroon Creeks. These projects would only be considered for
implementation if other projects and strategies (including conservation) are not sufficient to
secure a sufficient long term water supply. The extended timing of changes in runoff patterns

 resulting from Climate Change represent a significant challenge in planning for long term
supplies since it is not possible to predict with accuracy what future conditions will present. A
significant note in addition to the uncertainty that any of these projects would be needed is that
all of these alternatives will require substantial investigation to develop preliminary designs,
costs and to evaluate the impact on streams before proceeding. The cumulative amount of
supplemental water form Ruedi associated with long term projects is estimated at 360 acre feet
per year, resulting in a cumulative need of 400 acre feet per year from Ruedi under the current
USBR offering.
Salvation Ditch Pumpback and Roaring Fork Supply
The WMP considered an alternative to pump water from the Roaring Fork while providing an
exchange of water to the Salvation Ditch. Conceptually, this project would divert water (either
water from the Roaring Fork, or reclaimed water form ACSD, or a combination of both) from a
location near the ACSD plant and provide for an exchange of water with the Salvation Ditch.
This exchange would reduce the amount of water diverted from the Salvation Ditch headgate
(located near Stillwater Drive in East Aspen) and increase the available stream flow in the
Roaring Fork through Aspen. At the same time, this would potentially supply a new of potable
water available for treatment at the Hunter Creek treatment plant site. Since the diversion and
subsequent change would require a junior water right, this project would require augmentation
water to avoid damage to downstream water users.
New Groundwater and Roaring Fork Supplies
The WMP includes provision of a new treatment facility using Roaring Fork Supplies. A number
of alternative treatment sites are available on existing City owned property. This project could be
supplemented by additional groundwater sources from rights such as the Durant Mine Tunnel
(existing non-potable water source) or other new or existing groundwater sources. The additional
uses may require augmentation to avoid damage to senior downstream users.
New Reservoir Storage
Aspen relies on direct runoff from snowmelt and has no significant quantity of surface water
storage. Aspen holds conditional water rights for raw water storage on both Castle and Maroon
Creek totaling in excess of 15,000 acre feet. The existing WMP makes it clear that other less
costly and intrusive alternatives would be implemented prior to constructing reservoirs.
However, it would be unwise to eliminate these two projects as options until other options are
evaluated more fully and proven as a feasible means of addressing future potential changes in
climate and resulting runoff patterns. If constructed, these two reservoirs could benefit from
Ruedi water in two ways. A minimum pool could be established for aesthetic and recreational
purposes, which may be returned as a result of the permitting process. Second, future oil shale
development may, to the extent it occurs, develop a more or less permanent water shortage on
the Colorado River mainstream, limiting opportunities to store water form Castle and Maroon
Creek. As supplemental release of Ruedi water would alleviate this condition (in part) and
increase opportunities to store water from Castle and Maroon Creeks.