HomeMy WebLinkAboutMemo - Mail Packet - 8/10/2021 - Memorandum From Eileen Dornfest Re: Halligan Water Supply Project: Quarterly Report And Dam Concepts
Utilities
electric · stormwater · wastewater · water
700 Wood Street
PO Box 580
Fort Collins, CO 80522
970.212.2900
V/TDD 711
utilities@fcgov.com
fcgov.com/utilities
M E M O R A N D U M
DATE: August 2, 2021
TO: Mayor Arndt and Councilmembers
FROM: Eileen Dornfest, Special Projects Manager
THROUGH: Darin Atteberry, City Manager
Kelly DiMartino, Deputy City Manager
Theresa Connor, Interim Utilities Executive Director
RE: Halligan Water Supply Project: Quarterly Report and Dam Concepts
The purpose of this memo and attachment is to provide the following information about the Halligan Water
Supply Project (Halligan Project or Project):
1. A quarterly update on the Project
2. An update on the design of the dam for the enlarged Halligan Reservoir
BOTTOM LINE
Staff continue to lead the Halligan Project through 30% design and several required state and federal
permitting processes. A quarterly Project update is attached. The permitting schedule continues to drive
the overall Project schedule.
Preliminary design activities have identified two potential dam concepts for the enlarged Halligan
Reservoir. Staff are evaluating the feasibility of the two concepts, and one concept will be progressed to
30% design by early 2022. An updated Project cost estimate will be developed and shared with City
Council in 2022.
HALLIGAN DAM CONCEPTS
The existing Halligan Dam is a concrete arch dam that was constructed in 1909. The current design
concept for the enlargement of Halligan Reservoir is to increase the height of the existing dam by 25 feet
to provide additional water storage needed for resiliency of future Fort Collins Utilities’20 water supply.
Preliminary design work began in 2020 and included several analyses in and around the existing dam.
Preliminary design efforts revealed that two viable dam concepts exist for enlarging Halligan
Reservoir:
Existing Dam Concept: The existing dam would need to be significantly modified to meet current
regulations and hold up to the increased scrutiny given to dam design following the 2017 Oroville
Dam spillway failure. Modifying the 112-year-old dam will present unique challenges during
design and construction.
Adjacent Dam Concept: An additional dam concept was identified which would entail building a
replacement dam immediately downstream of and adjacent to the current dam.
Cost: The two dam concepts are similar in cost given the information available at this early stage
of design.
Impacts: Environmental impacts of the two dam concepts are also similar.
DocuSign Envelope ID: B764EDF8-A8CB-4762-97F5-3FE9CA700F39
Preliminary analyses indicate that the Adjacent Dam Concept could provide several benefits over the
Existing Dam Concept, including:
Easier incorporation of modern construction techniques and materials.
Improved long-term functionality and increased efficiency for operations.
Improved maintenance access and possible reduction in long-term maintenance costs.
Reduced construction risk by:
o Allowing better management of water and sediment during construction.
o Reducing uncertainties and design/construction challenges related to enlarging a 112-
year-old-dam.
Reduced impacts to reservoir operations during construction.
To ensure we have the best project not only for Fort Collins Utilities customers but also for the
environment, staff are performing due diligence activities to evaluate the Adjacent Dam Concept for
feasibility, effectiveness, and environmental impacts. More information will be shared with City Council
as additional data are gathered and a dam concept is chosen.
NEXT STEPS
Design activities over the next six months will focus on evaluating the feasibility of the Adjacent Dam
Concept and advancing the selected dam concept to a 30% level of design. City Council will be notified
once a dam concept is selected.
After 30% design is complete, an updated Project cost estimate will be developed and shared with City
Council in 2022.
If there are any questions about this update or the Halligan Water Supply Project, please contact Eileen
Dornfest at 970-416-4296 or edornfest@fcgov.com.
Attachments:
Attachment 1: Q3 Quarterly Report
CC: Water Commission
Lance Smith, Utilities Finance Director
Donnie Dustin, Water Resources Manager
Liesel Hans, Interim Deputy Director - Water Resources & Treatment Operations
Mark Kempton Interim Deputy Director - Water Resources & Treatment Operations
DocuSign Envelope ID: B764EDF8-A8CB-4762-97F5-3FE9CA700F39
HALLIGAN WATER
SUPPLY PROJECTUPDATE
BACKGROUND
The Halligan Water Supply Project would enlarge
Halligan Reservoir, an existing reservoir on the North
Fork of the Poudre River, to meet the demand of
future Fort Collins Utilities’ water customers and
provide increased reliability for existing customers
in the event of emergencies, drought and climate-
change uncertainties. The project would expand the
reservoir by about 8,100 acre-feet. For context, an
average single-family home in Fort Collins uses just
over a quarter of an acre-foot of water each year
(about 85,000 gallons).
The project reached a milestone in November 2019
after many years of hard work, when the draft
EIS was released. The final Environmental Impact
Statement (EIS) will likely be released in 2022.
Permits are required from the U.S. Army Corps
of Engineers (Corps) and other federal, state and
county agencies to enlarge Halligan Reservoir. Staff
continue to support preparation of a final EIS by
the Corps. Additionally, staff are currently working
toward other permitting processes, including the
Fish and Wildlife Mitigation Plan, 401 Water Quality
Certification and Biological Assessment.
PROGRESS UPDATE
Permitting and Mitigation
• The Corps is preparing the final EIS, which will include
information learned during engineering design. The final
EIS is anticipated to be released in 2022.
• Staff are working closely with Colorado Parks and
Wildlife to develop concepts for the Fish and Wildlife
Mitigation and Enhancement Plan. This plan is
anticipated to be complete in 2022.
• Staff continue to work toward development of an
application for a 401 Water Quality Certification from the
Colorado Department of Public Health and Environment
– Water Quality Control Division.
Public Engagement & Communication
• The Fish and Wildlife Mitigation and Enhancement Plan
and the 401 Water Quality Certification both include a
public process. More information about those processes
will be forthcoming as that timeframe approaches.
• Metrics below represent touchpoints on the project since
the start of 2021.
Property Acquisition and Easements
• Staff continue to work toward acquiring easement
agreements for permitting and design access.
Preliminary Design
• Preliminary design activities are underway.
• Two dam alignment concepts are being evaluated for an
enlarged Halligan Reservoir:
1. A significant modification to the existing dam
2. A replacement dam adjacent and immediately
downstream of the existing dam.
• Additional site data is being collected this summer to
aid in development of 30% design. This phase of design
is anticipated to be complete in 2022 and will provide
essential information for development of a refined
project cost estimate.
August 2021
Ecological surveying along the North Fork of the Poudre River.
More background information is available in the
Briefing Book which was distributed to City Council
in June.
Web visits
Social media reach
Event attendees
Meetings/presentation attendees
Emails
2,600+
1,400+
950+
700+
145
DocuSign Envelope ID: B764EDF8-A8CB-4762-97F5-3FE9CA700F39
For more information, visit fcgov.com/halligan
Eileen Dornfest, Special Projects Manager • 970-416-4296 • halligan@fcgov.com
Auxiliary aids and services are available for persons with disabilities, V/TDD 711.Esta información puede ser traducida, sin costo para usted, 970-212-2900.Utilities
ANTICIPATED COSTS
In 2019, the total project cost was estimated to be
between $100M - $150M, based on concept-level
details. The cost estimate was presented as a
range to reflect uncertainties about the project
schedule, environmental mitigation requirements,
access needs, and conceptual nature of the
design. Costs are predominantly influenced by
factors outside of the City’s control, such as the
permitting schedule and permitting and
environmental mitigation requirements. Current
information indicates the costs will exceed the
upper end of this range, but detailed information
will not be available until after 30% design is
complete in 2022.
Cost Analysis
Costs will continue to be updated as new information is obtained throughout the permitting and design process. Updated
cost estimates and other dependent and independent metrics will be evaluated at future project milestones to verify that
the Halligan Project remains the most cost-effective water supply solution for Utilities’ customers. In the meantime, staff
continue to focus on those items the City can influence or control, such as identifying and mitigating risks, value
engineering, and disciplined spending practices.
HALLIGAN WATER SUPPLY PROJECT SCHEDULE
This schedule reflects current
understanding of project
timelines and is subject to
change based on permitting
requirements. The color
changes in the bars represent
uncertainty in the timeline.
‘06-’18 ‘19 ‘20 ‘21 ‘22 ‘23 ‘24 ‘25 ‘26 ‘27 ‘28 ‘29
Federal Permitting
Other Permitting
Preliminary Design
Final Design
Construction
— Record of Decision
— Draft EIS Release
— Draft EIS Comment Period
— Prepare & Release Final EIS
WE ARE HERE
— Purpose & Need, Environmental Studies, Draft EIS Development
Figure 1: Dollars Spent vs. Projected Costs*
Spent to date: $23.4M Projected future costs Appropriated funds remaining: $12.3MCost in Millions*Project costs shown in the charts are based on information available in 2019. These costs
will be updated again in 2022.
HOW THE PROJECT RELATES TO COUNCIL PRIORITIES
Provides the resiliency
needed to maintain the
level of service expected
by customers.
Protects and enhances
instream river flows.
Improves and
accelerates stream/
riparian restoration.
0
10
20
30
40
50
60
70
80
MITIGATIONDESIGN & CONSTRUCTIONPUBLIC OUTREACHPROPERTY ACQUISITION PERMITTING
DocuSign Envelope ID: B764EDF8-A8CB-4762-97F5-3FE9CA700F39