Administrative
Report
H.8., File # 23-6683 Meeting Date: 10/17/2023
To: MAYOR AND CITY COUNCIL
From: TED SEMAAN, PUBLIC WORKS DIRECTOR
TITLE
APPROVE AN AMENDMENT TO THE AGREEMENT WITH BKF ENGINEERS FOR ADDITIONAL
GEOTECHNICAL AND DESIGN SERVICES FOR THE KINGSDALE AVENUE RESURFACING PROJECT, FROM 182ND STREET TO GRANT AVE, JOB NO. 40880, FOR AN ADDITIONAL AMOUNT OF $67,362 AND TO EXTEND THE TERM TO DECEMBER 13, 2025
EXECUTIVE SUMMARY
Approval of this Amendment will authorize BKF Engineers to perform additional design services, which includes traffic engineering, geotechnical investigation, pavement analysis, and continuing development of the Plans, Specifications, and Estimate (PS&E) for the Kingsdale Avenue Resurfacing Project from 182nd Street to Grant Avenue Project, Job No.40880 (Project).
On December 14, 2021, the City Council awarded a consulting services contract to BKF Engineers for the Project. The design requirements included the evaluation of subsurface conditions. The geotechnical investigation per the original Agreement included collection and analysis of existing pavement and base soil samples at three boring locations. Data obtained from the three boring locations indicated additional investigation was necessary to appropriately design the Project.
The City negotiated the proposed contract amendment for the additional design and investigation services which will raise the not to exceed value of the contract by $67,362, to a new total amount not to exceed $140,976.37. The Project is funded by transportation restricted Prop C funds.
BACKGROUND
On August 11, 2021, City staff initiated an RFP process to solicit proposals from qualified engineering firms for design of the Project. On September 9, 2021, the City received six proposals. Out of the six proposals, BKF Engineers was found to have the best combination of experience on similar projects, price, and references.
On December 14, 2021, the City Council awarded a consulting services contract to BKF Engineers for the Project with a total not to exceed amount of $74,563.
The project’s objective is to rehabilitate Kingsdale Avenue between 182nd Street and Grant Avenue through both resurfacing (grind and overlay) and full depth reconstruction. Access ramps, curbs, gutters, and drainage facilities will also be repaired as necessary. Completion of Project design was anticipated in mid-2023 with advertisement for construction bids to follow thereafter. However, the initial geotechnical investigation did not provide a clear understanding of existing subsurface
H.8., File # 23-6683 Meeting Date: 10/17/2023
initial geotechnical investigation did not provide a clear understanding of existing subsurface conditions. This triggered the need for additional geotechnical investigation to properly scope the upcoming Project.
Specifically, the original geotechnical investigation scope of work included collection and analysis of existing pavement and base soil samples at three boring locations. Data obtained from the three boring locations provided a wide range of pavement and soil conditions and were non-conclusive for the base and pavement design of the Project. Additional geotechnical investigation is necessary and the consultant recommended to use the technology of 3D Ground Penetrating Radar (GPR) that scans the entire corridor of the street.
The process employs multi-frequency signals to scan the subsurface. Data obtained from the continuous 3D Scanning is used to compare with the frequency of known pavement types and plotted on a Google Earth Map. The variation of the frequency demonstrates change of layers of the existing pavement and base. It also provides information about underground utilities, if any are present.
It has been noted by the engineering team that the recently completed Transit Center Project required change orders to accommodate unforeseen subsurface conditions. The additional recommended 3D Scanning analysis along Kingsdale should help avoid similar construction issues.
The expenditure of additional funds will reduce uncertainty about the soil conditions, structures, and utilities that are in place under the existing roadway and will decrease the likelihood of project change orders over the life of the construction contract, once awarded.
The City negotiated with the consultant for additional geotechnical investigation, data analysis, and the preparation of the follow up report. The proposed amendment also includes refinement of the PS&E following the City’s review and acceptance of the 3D subsurface conditions. The proposed amendment adds $67,362 to the original Agreement, increasing the total contract amount to $140,976.37 and extends the contract period to December 13, 2025. The Project is funded by Prop C and does not impact the City’s General Fund.
COORDINATION
The scope of work identified in the contract has been coordinated by the Public Works Department.
The City Attorney’s Office approved the amendment as to form.
FISCAL IMPACT
FUNDING EXPENDITURES
Kingsdale Ave Resurfacing BKF Engineers
Project Acct (Prop C) $140,976.37 Original Agreement $73,614.37 Amendment No.1 $67,362.00
Total $140,976.37 Total $140,976.37
APPROVED BY:
Mike Witzansky, City Manager
ATTACHMENTS
H.8., File # 23-6683 Meeting Date: 10/17/2023
· Agmt - First Amendment to BKF Engineers Contract
· Agmt - BKF Engineers Consulting Services Original Contract, December 14, 2021