To: Board of Supervisors
Department or Agency Name(s): Sonoma County Public Infrastructure
Staff Name and Phone Number: Johannes J. Hoevertsz, 707-565-2550
Vote Requirement: 4/5th
Supervisorial District(s): Fifth
Title:
Title
Sixth Amendment to the Professional Services Agreement with Dewberry Engineers, Inc. for design of the Wohler Road Bridge over Russian River Seismic Retrofit (County Project No. C01136)
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Recommended Action:
Recommended action
Approve and authorize the Director of Sonoma County Public Infrastructure to execute a no-cost Sixth Amendment to the Professional Services Agreement with Dewberry Engineers, Inc. for the Wohler Road Bridge over Russian River Seismic Retrofit Project.
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Executive Summary:
Sonoma County Public Infrastructure (SPI) is requesting that the Board approve the Sixth Amendment to the Professional Services Agreement with Dewberry Engineers, Inc. (formerly Drake Haglan and Associates, Inc.) to extend the term of the Agreement for two years through December 31, 2028, at no additional cost. The proposed Amendment will allow Dewberry to continue providing construction support services for the Wohler Road Bridge at Russian River Seismic Retrofit Project.
Discussion:
The Big Wohler Road Bridge Retrofit Project (County Project Number C01136) is the largest and most complex bridge project ever undertaken by the County of Sonoma. The bridge is located in rural, western Sonoma County approximately 10 miles northwest of the city of Santa Rosa. The project will retrofit the existing historical but seismically deficient one-lane Wohler Road Bridge (Bridge Number 20C-0155), with a new lightweight concrete deck, seismic isolation bearings and joints, steel truss reinforcement and foundation reinforcement. These improvements are designed to meet current California Department of Transportation (Caltrans) and American Association of State Highway and Transportation Officials (AASHTO) seismic design criteria and reduce the risk of bridge collapse during an earthquake. Due to the age, historic character, location, and complexity of the structure, development and implementation of the seismic retrofit has required extensive environmental, geotechnical, hydraulic and hydrologic studies, utility coordination, architectural evaluation, and engineering and design services.
Following a competitive Request for Proposals process, on September 24, 2013, the Board awarded a contract to Drake Haglan and Associates, Inc., (now Dewberry Engineers, Inc.,) to provide engineering and design services for the Project for a not-to-exceed amount of $653,454 and a term ending December 31, 2016. Since awarding the contract the Board has approved the following:
• On May 24, 2016, the Board approved the First Amendment, increasing the not-to-exceed amount to $824,344 and extending the contract term to December 31, 2019.
• On July 10, 2018, the Board approved the Second Amendment for further seismic, design and engineering work, increasing the not-to-exceed amount to $969,877 and extending the term of the Agreement to December 31, 2021.
• On August 24, 2021, the Board adopted a Mitigated Negative Declaration and Mitigation Monitoring Program and approved the Project.
• On December 7, 2021, the Board approved the Third Amendment for a no-cost time extension, extending the term of the Agreement until December 31, 2025.
• On February 6, 2024, the Board awarded a construction contract to Ghilotti Construction Company.
• On April 30, 2024, the Board approved the Fourth Amendment for services during construction, increasing the not-to-exceed amount to $1,405,771.60 and extending the term of the Agreement to December 31, 2026, and
• On August 13, 2024, the Board approved a Fifth Amendment, increasing the total not-to-exceed amount to $1,550,935.67, with no change in the term of the Agreement.
SPI is requesting Board approval of a Sixth Amendment to the Professional Services Agreement with Dewberry Engineers, Inc. to extend the term of the Agreement for two years, through December 31, 2028, at no additional cost. Construction was originally anticipated to occur over two construction seasons and is now anticipated to continue through late 2026 or early 2027. The proposed Amendment will provide sufficient time for Dewberry to continue providing construction support services through completion of construction.
Strategic Plan:
This item directly supports the County’s Five-year Strategic Plan and is aligned with the following pillar, goal, and objective.
Pillar: Resilient Infrastructure
Goal: Goal 3: Continue to invest in critical road, bridge, bicycle, and pedestrian infrastructure.
Objective: Objective 4: Identify and retrofit bridges in County that are at high risk for damage during earthquakes.
Racial Equity:
Was this item identified as an opportunity to apply the Racial Equity Toolkit?
No
Prior Board Actions:
8/13/2024: Board approves Fifth Amendment to the Agreement with Dewberry (formerly Drake Haglan and Associates, Inc.).
4/30/2024: Board approves Fourth Amendment to the agreement with Dewberry (formerly Drake Haglan and Associates, Inc.).
2/06/2024: Board awards construction contract to Ghilotti Construction Company, Inc.
12/07/2021: Board approves Third Amendment to the agreement with Dewberry (formerly Drake Haglan and Associates, Inc.).
7/10/2018: Board approved Second Amendment to the agreement with Drake Haglan and Associates, Inc.
5/24/2016: Board approved First Amendment to the agreement with Drake Haglan and Associates, Inc.
9/24/2013: Board approved agreement with Drake Haglan and Associates, Inc. for engineering design work.
Fiscal Summary
Narrative Explanation of Fiscal Impacts:
There is no fiscal impact associated with this Board action. The proposed Sixth Amendment is a time-only extension and does not increase the not-to-exceed amount of the Agreement.
Narrative Explanation of Staffing Impacts (If Required):
None.
Attachments:
Sixth Amendment with Dewberry Engineers Inc.
Related Items “On File” with the Clerk of the Board:
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