To: Honorable Mayor and Members of Town Council
From: Mark Marlowe, P.E., Utilities Director
David Van Dellen, P.E., Stormwater Manager
Title
Resolution: Approving a Construction Contract with Sabell’s Enterprises LLLP for the Heckendorf Pond Rundown Improvement Project
Body
________________________________________________________________________________
Executive Summary
The Utilities Department is seeking Town Council approval of a resolution (Attachment A) awarding a Construction Contract (Exhibit 1) to Sabell’s Enterprises LLLP (Sabell’s) for the Heckendorf Pond Rundown Improvement Project in the amount of $253,021plus a 15% staff-managed contingency in the amount of $37,953, for a total project authorization of $290,974. This project will be funded through the Stormwater Enterprise Fund. Staff plans to complete the project this fall.
History of Past Town Council, Board & Commissions, or Other Discussion
The Heckendorf Regional Detention Pond is located within Heckendorf Ranch Filing 1, near the intersection of Crystal Valley Parkway and Plum Creek Boulevard, east of the Union Pacific Railroad. Construction of the pond improvements were completed by a private land developer and accepted by the Town in 2007. In July 2014, the Town became aware of a failure at the channel rundown at the southeast corner of the pond. This failure has led to the unraveling of over 50 feet of Town owned dual 42" RCP storm sewer above the pond. Although the specific cause of failure is unknown, it appears that surface water intrusion on the underside of the rundown structure created a void that eventually collapsed the system over time.
Since 2007, the Town has made tremendous enhancements in our design standards and construction oversight programs that help prevent premature infrastructure failure such as this.
Utilities staff presented this construction agreement to the Utilities Commission at their regularly scheduled meeting held on August 26, 2015.
Discussion
The Town underwent a thorough review of alternatives to ensure that the replacement system is sustainable for the life cycle of the utility installation. Three alternatives were analyzed for reconstructing the outfall and rundown. Staff has selected a fully piped option that includes a single 54” RCP storm sewer constructed to the bottom of the pond as the most suitable and cost effective alternative. Also included are storm inlets at the top of the pond to capture and convey overland sheet flow to minimize future erosion on the pond embankment. The proposed improvements will minimize the risk of future failure.
The Town solicited construction bids based on preliminary design quantities for two of the three alternatives. An increased contingency of 15% is included to account for uncertainties in the preliminary design. This design-build approach allows the Town to complete the necessary repairs on an accelerated schedule, and minimize construction costs as much as possible.
Bids were solicited from three qualified contractors and are summarized below:
Contractor Bid Price
53 Corporation $269,412
Hudick Excavating No bid
Sabell’s Enterprises $253,021
We recommend this project be awarded to Sabell’s as the confirmed lowest responsible and qualified bidder. Sabell’s has completed similar work for the Town over the past several years. Construction is anticipated to begin in October and will be substantially complete in December 2015, weather permitting.
Budget Impact
Utilities budgeted $80,000 in 2015 in the Stormwater Fund Capital Projects Account 212-4475-444.78-13 Crystal Valley Pkwy Stm Rpr. Additionally, funds will be transferred from Stormwater Fund Capital Projects Account 212-4475-444.77-13 Douglas Lane Tributary Stabilization in the amount of $236,000 to cover the remaining cost of the project. There will be no net increase to the Stormwater Fund 2015 capital budget with the implementation of this project. This will delay the implementation of a portion of the Douglas Lane Tributary Stabilization Project by a year as funds that would have been used for this project will be used for this emergency repair
Staff Recommendation
Staff recommends Town Council approval of the resolution awarding a Construction Contract to Sabell’s Enterprises LLLP for the Heckendorf Pond Rundown Improvement Project in the amount of $253,021plus a 15% staff-managed contingency in the amount of $37,953, for a total project authorization of $290,974.
Proposed Motion
I move to approve a Resolution approving a Construction Contract with Sabell’s Enterprises LLLP for the Heckendorf Pond Rundown Improvement Project.
Attachments
Attachment A: Resolution
Exhibit 1: Construction Contract