To: Members of the Castle Rock Water Commission
From: Mark Marlowe, P.E., Director of Castle Rock Water
David Van Dellen, P.E., Assistant Director
Roy Gallea, P.E., Engineering Manager
Josh Hansen, P.E., CIP Project Manager
Title
Resolution Approving a Variance Pursuant to Chapter 9.16.070E of the Castle Rock Municipal Code for the Cobblestone Ranch Water Storage Tank 18 Project [Pleasant View Drive and Antelope Place]
Town Council Agenda Date: October 1, 2024
Body
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Executive Summary
Construction of Cobblestone Ranch Water Storage Tank 18 began in July 2022 and is nearing completion. Castle Rock Water is seeking Town Council approval of a variance to allow overnight construction work for the Cobblestone Ranch Water Storage Tank 18 Project. DN Tanks was retained by the Town to construct the project in 2022. In order to complete the project, DN Tanks needs to install an interior tank liner overnight. Night installation is necessary as the liner requires declining ambient temperatures during application to allow the coating to cure correctly.
DN Tanks will complete the construction work from 4pm to 3am over two weeks in October. Local residents have been notified in advance of the work. Noise and light mitigation measures will be installed during construction activities.
History of Past Town Council, Boards & Commissions, or Other Discussions
On March 15, 2022 Castle Rock Town Council voted unanimously to approve a construction contract in the amount of $4,386,765 with DN Tanks along with authorization of $438,700 in staff-managed contingency to complete construction of Cobblestone Ranch 2 MG Water Storage Tank 18.
On April 4, 2022 Douglas County Planning Commission voted unanimously to approve the Location and Extent application for the Tank 18 Blue Zone Transmission Project.
On August 16, 2022 Castle Rock Town Council voted unanimously to approve a construction contract in the amount of $4,081,473 with Reynolds along with authorization of $408,147 in staff-managed contingency to complete the construction of Tank 18 Blue Zone Transmission Project.
On March 21, 2023 Town Council voted unanimously to approve a Variance Pursuant to Chapter 9.16.070.E of the Castle Rock Municipal Code for Nighttime Construction Activities Related to the Tank 18 Blue Zone Main Project.
Notification and Outreach Efforts
Local outreach and notification of this project has been ongoing including mailed project information letters, phone calls and emails.
Local residents surrounding Tank 18 have been contacted recently to inform them of the proposed night work to install the CIM topcoat.
Discussion
In March 2022 the Town contracted with DN Tanks to construct a new 2 million-gallon potable water storage tank, Tank 18, to support the Cobblestone Ranch development. Construction of the water tank began in July and the concrete structure was generally complete by November 2022. In 2022 the Town contracted with Reynolds Construction to install 8,000 feet of water pipeline to connect the blue zone pipeline in Castle Oaks Drive to Tank 18. Pipeline construction was complete in July 2023. Prior to putting the tank in service backfilling, testing and tank site work and installation of the interior tank liner are required to be completed.
Equipment that will be used at night over two weeks in October by DN Tanks includes a forklift, generator, fans and exterior and interior lighting. Noise and light mitigation measures will be used throughout construction activities. Staging will be near the tank to minimize vehicle movement up and down the access road at night, forklifts will be operated in the afternoon, sound dampening material will be erected around generators, and lighting will be minimal to allow for safety of individuals walking around the base of the tank at night to access stockpiled materials.
Budget Impact
There is currently no anticipated project budget impact related to the night construction work.
Staff Recommendation
Staff requests approval of a Resolution approving a variance pursuant to Chapter 9.16.070E of the Castle Rock Municipal Code for the Cobblestone Ranch Water Storage Tank 18 Project.
Proposed Motion
“I move to recommend to Town Council approval of ___________________ as presented”
Alternative Motions
“I move to approve the resolution as introduced by title, with the following conditions: (list conditions).
“I move to continue this item to the Town Council meeting on _____ date to allow additional time to (list information needed).”
Attachments
Staff Report
Attachment A: Resolution (Not Attached)
Attachment B: Map of Area Impacted by Night Work