ASPEN CITY COUNCIL WORK SESSION
MEMORANDUM
TO:

Mayor and City Council

FROM:

Margaret Medellin, Utilities Portfolio Manager

THRU:

Scott Miller, Director of Public Works;
Dave Hornbacher, Director, Utilities and Environmental Initiatives;

DATE OF MEMO: June 30, 2017
MEETING DATE: July 10, 2017
RE:

Resolution 102, Series of 2017: Amendment to contract to analyze the
potential use of In-Situ Reservoirs as a component of Aspen's Integrated
Water System

REQUEST OF COUNCIL: Staff requests Council amend its contract with Deere and Ault
Consultants, Inc. in the amount of $116,000 for professional services to analyze the potential use
of in-situ reservoirs as a component of Aspen’s Integrated Water System.
PREVIOUS COUNCIL ACTION: On October 10, 2016, Council passed Resolution #141,
Series of 2016 directing staff to implement certain water management measures to improve
resiliency against future climate change impacts and other system changes. Included in this
Resolution was the direction to:
Enhance and increase the City’s efforts to investigate alternative locations and sizing
requirements of the Maroon Creek Reservoir and/or Castle Creek Reservoir, and to report
findings back to City Council for further consideration and action as appropriate.
On May 27, 2017 Council passed Resolution #60, Series of 2017 approving a contract with
Deere and Ault Consultants to investigate the potential use of in-situ reservoirs as a component
of Aspen’s Integrated Water System.
BACKGROUND: The City Utilities and Environmental Initiatives Department is responsible
for assuring Aspen has a safe, legal and reliable water supply, now and into the future. To this
end, the City operates an integrated water system, which leverages many supply, storage,
operational and management techniques to optimize the City’s resources.
DISCUSSION: Water storage is a component of an integrated water system which allows
efficient operation of resources and reliable delivery of water even during times of emergency or
shortage. Aspen has minimal storage in its system, with less than a day of water supply available
as storage during peak times. To address this vulnerability, the City has maintained its
conditional water storage rights on Maroon and Castle Creeks, and in addition continues to seek

 alternatives to these surface reservoirs. In-situ reservoirs have been identified as a promising
alternative to augment, and potentially reduce, the need for surface storage.
In-situ reservoirs create sub-surface water storage through the installation of slurry walls
extending from the surface to bedrock. With suitable geology, these slurry walls can create an inplace, subsurface storage vessel. As needed, water would be withdrawn from the in-situ reservoir
via wells and pumped to a treatment facility. This amendment will also consider the use of open
water storage in alternative locations.
FINANCIAL IMPACTS: The execution of the attached contract with Deere and Ault will
require additional 2017 budget authority in the amount of $116,000. Water Fund has a sufficient
balance and reserves to cover this additional budget request.
ENVIRONMENTAL IMPACTS: The City is committed to reducing its footprint (carbon and
water) and fighting climate change, but even with this effort and action the City recognizes that it
is best practice to plan for a future that looks very different than today. The City’s efforts to
develop its integrated water system are necessary to ensure the City’s resiliency.
RECOMMENDED ACTION: Council is requested to approve the amendment to its contract
with Deere and Ault Consultants, Inc., through adoption of Resolution 102, Series of 2017.

CITY MANAGER COMMENTS:

ATTACHMENTS:
Attachment A – Resolution 102, Series of 2017
Attachment B – Amendment to Contract with Deere and Ault Consultants, Inc.