STRATEGIC PRIORITY: Transportation & Infrastructure
AGENDA DATE: June 12, 2024
COUNCIL DISTRICT(S): 10
DEPARTMENT: Water Utilities Department
EXECUTIVE: Majed Al-Ghafry
______________________________________________________________________
SUBJECT
Title
Authorize an increase in the construction services contract with SYB Construction Co., Inc., for the emergency replacement of a 60-inch diameter sanitary sewer pipeline behind 11400 Central Expressway - Not to exceed $676,310.00, from $21,003,141.50 to $21,679,451.50 - Financing: Wastewater Construction Fund
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BACKGROUND
Dallas Water Utilities (DWU) owns and operates a 60-inch diameter concrete sewer pipeline near the Cottonwood Trail behind 11400 Central Expressway. The existing pipeline was built in 1972 and has structurally failed, forming a sink hole at this location. There are two 48-inch diameter sanitary sewer pipelines discharging into this interceptor.
DWU investigated the 60-inch interceptor from manhole to manhole and found the pipe to be in very poor condition. The inspection report revealed that the top part of the pipeline has deteriorated (visible rebar and missing concrete pieces) and the bottom part was not visible due to high flows. The depth of the pipeline is 23 feet, and the peak flow is 55 million gallons per day. A 9-foot segment of pipe is missing where the sinkhole has surfaced and approximately 400 feet of the wastewater pipeline needs emergency replacement.
Due to the poor condition of the pipeline, its depth, the high volume of wastewater flow, and the adverse site conditions, the resources of a private construction company will be necessary. DWU received quotes from contractors with experience in completing similar repairs. SYB Construction Co., Inc. provided the best quote to complete the work and submitted a final cost proposal of $676,310.00 on May 16, 2024. The estimate was reviewed by DWU and found to be a reasonable cost for the significance and difficulty of the work to be performed. Given the failure of the existing pipeline and threat of a more extensive structural failure that would impact the Cottonwood Trail and cause a Sanitary Sewer Overflow, DWU recommends immediately moving forward with the work utilizing the services of SYB Construction Co., Inc.
This action will authorized Changer Oder No. 1 to the construction services contract with SYB Construction Co., Inc. for emergency replacement of a 60-inch diameter sanitary sewer pipeline behind 11400 Central Expressway, in an amount not to exceed $676,310.00, increasing the contract amount from $21,003,141.50 to $21,679,451.50.
ESTIMATED SCHEDULE OF PROJECT
Begin Construction June 2024
Complete Construction August 2024
PRIOR ACTION/REVIEW (COUNCIL, BOARDS, COMMISSIONS)
On November 9, 2022, the City Council authorized a construction services contract for the installation and rehabilitation of water and wastewater mains, the replacement of water transmission valves, and the extension of water and wastewater mains to unserved areas at 45 locations by Resolution No. 22-1699.
FISCAL INFORMATION
|
Fund |
FY 2024 |
FY 2025 |
Future Years |
|
Wastewater Construction Fund |
$676,310.00 |
$0.00 |
$0.00 |
Construction $21,003,141.50
Change Order No. 1 (this action) $ 676,310.00
Total Project Cost $21,679,451.50
OWNER
SYB Construction Co., Inc.
Brian Wood, Vice President
MAP
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