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): First, Fourth and Fifth
Title:
Title
Public Construction Contract Change Orders
End
Recommended Action:
Recommended action
Make findings and authorize the Director of Sonoma Public Infrastructure to execute construction contract change orders and amend the respective contract amounts necessary to address differing site conditions and accelerated work schedules to meet environmental permit deadlines, maintain emergency access, and minimize impacts to nearby businesses during construction for Wohler Bridge Seismic Retrofit Project (Project number C01136) and Westside Road and Cavedale Road Emergency Slide Repair Projects (Project numbers C42431, C12432, & C42430).
end
Executive Summary:
The Department of Public Infrastructure (SPI) seeks Board approval for the following construction contract change orders:
-Wohler Road Bridge over the Russian River Seismic Retrofit Project: Approve and authorize the Director to execute a change order of up to $700,537.89, for a total amount of contract changes of up to $2,300,000. These are for changes in work scope due to previously unforeseen conditions encountered below the river and for an accelerated work schedules.
- Westside Road Emergency Slide Repair Project: Approve and authorize the Director to execute change orders in a cumulative amount of up to $750,000. These changes are due to differing conditions and accelerated work schedules utilized to reopen the roads as quickly as possible.
- Cavedale Road Project: Approve and authorize the Director to execute a change orders in a cumulative amount of up to $919,256 also due to differing conditions and the need to reopen the roads by accelerating work schedules.
Discussion:
This item includes the Wohler Bridge Seismic Retrofit Project, which is the Department’s largest construction project to date, as well as multiple storm damage projects caused by the February 2025 storms, which resulted in extensive road damage and required road closures.
SPI is requesting authority to execute construction contract change orders, which are needed due to differing site conditions and accelerated work schedules, which required compressing and intensifying the construction sequence to ensure timely completion and required contractors to add additional crews and work extensive overtime. In some cases, such as the Wohler Bridge Project, the contractor operated 24 hours a day for nearly a month to meet critical deadlines.
Wohler Bridge
The Wohler Road Bridge over Russian River Seismic Retrofit Project is a large and complex bridge project, involving retrofitting the existing historical, seismically deficient one-lane Wohler Road Bridge (Bridge Number 20C-0155), with a new lightweight concrete deck, seismic isolation bearings, steel truss reinforcement, and foundation reinforcement.
On February 6, 2024, the Board awarded a construction contract for the Project to Ghilotti Construction Company, Inc. in the amount of $17,994,621.11.
Planned foundation work within the river included construction of an enlarged pier footing secured by 10 cast-in-drilled-hole piles. On the first day of drilling an unknown concrete slab covering a layer of large boulders was discovered. Standard drilling equipment could not penetrate the concrete layer, and alternate construction methods, including larger equipment, were employed. The coffer dam surrounding the work area was enlarged to avoid the obstruction, resulting in increased water disposal to keep the work area dry. After significant delays due to the obstruction, the schedule was accelerated by extending shift hours, weekend work, and overnight shifts to complete in-water construction prior to the permitted work end date of October 15, 2025.
Costs to support the changed work are estimated at $2,300,000. Compensation for the additional work is required by the contract specifications for buried, man-made objects and differing site conditions. Without acceleration efforts, the in-water work would have extended into a second season of work occurring in the water. A second season would have significantly escalated costs by triggering new permitting, removal and reconstruction of the in-water work pad, and potential damage to partially completed work that was not designed for winter river flows.
Funding for the construction project is 88.7% Federal Highways Administration (FHWA) funds administered by Caltrans. SPI has conferred with Caltrans during the project, received assurance the costs are reimbursable and has submitted a request for reimbursement for this contract change order.
Westside Road Slide Repair
Westside Road is located in the west county, and generally runs west to east, linking the Hacienda area on the west side of Russian River. Westside Road is classified as a Major Collector. The Westside Road Emergency Repair Project resulted from severe road damage during the February 4, 2025, storm. A portion of the road slid down the adjacent hillside towards the Russian River. SPI responded by immediately closing the road and began working on plans and funding for emergency repairs.
On April 15, 2025, the Board adopted a resolution authorizing Road Commissioner Authority under Public Contract Code Section 20395 for Specified Flood Disaster Projects, which included this segment of Westside Road as well as the Cavedale Road repairs. The requested authorization enabled SPI to award the contract after the bid process was complete rather than returning to the Board for contract award.
The combination of closures on Wohler Road Bridge at the Russian River, Westside Road, and the restricted Wohler Road at Mark West Creek significantly impacted emergency services’ ability to respond efficiently. Time was of the essence for this project, since the subject roadways are critical roads for ingress and egress to large areas of the County, including for evacuation and emergency response purposes. In particular, repairs to Westside Road required urgency since those roads are the most viable and efficient detour routes in light of the periodic closures of Wohler Road for the Big Wohler Bridge for seismic repairs.
On May 5, 2025, the SPI Director awarded an emergency construction agreement for Westside Road to Ghilotti Construction Company, Inc. in the amount of $1,878,065.50, which included a 10% contingency.
During construction, SPI accelerated the work schedule by extending shift hours and added weekend work to complete construction and re-open the road as quickly as possible to minimize impacts to the community.
Costs to support the changed work are estimated at $750,000. Compensation for the additional work is required by the contract specifications for acceleration of work. Without acceleration efforts, the work would have extended the road closure and detour. Extending the work schedule would have significantly escalated costs by triggering new permitting, potential damage to partially completed work that was not designed for winter, and extended the time of road closure and detour. While the construction work is complete on Westside Road, SPI staff continues to review the construction invoices to verify the costs and confirm accurate payment to our contractors. The estimated cost of the change order before the Board today will allow SPI to pay the contractor as soon as possible.
Funding for the construction project was allocated from the Tobacco Securitization fund, which is available for use on capital projects, from the April 15, 2025 Board Item for an approved estimated amount of $1,500,000. The estimated total project cost now is $3,052,967. $1,552,967 of additional funding will need to be identified to cover the costs of this project as the project is financed with 100% of local funds. SPI in coordination with the County Executive Office will return to the Board with recommendations for a funding plan.
|
Westside Road Project Expenses |
|
Project Service |
Contractor / Supplier |
Award Amount |
Spent |
Additional Expenses |
Total Project Cost |
|
Construction Contract |
Ghilotti |
$1,878,066 |
$1,878,066 |
$750,000 |
$2,628,066 |
|
Design Contract |
Geo-Logics |
$224,850 |
$223,497 |
$0 |
$223,497 |
|
Force Account |
N/A |
$0 |
$151,405 |
$50,000 |
$201,405 |
|
TOTAL |
|
$2,102,916 |
$2,252,967 |
$800,000 |
$3,052,967 |
|
|
|
Tobacco Securitized Funding from 4/15/25 Board Item |
$1,500,000 |
|
Additional Funding Needed |
$1,552,967 |
Cavedale Road Slide Repair
Cavedale Road is located in the east county. Cavedale Road is classified as a Local Road and functions as a connection from State Route 12 in the Sonoma Valley to Napa County. The Cavedale Road Emergency Repair Project also resulted from severe road damage during the February 4, 2025, storm. A portion of the road slid down the adjacent hillside at two separate locations. SPI responded by immediately closing the road and began working on plans and funding for emergency repairs.
The closure of Cavedale Road impacted emergency services’ ability to respond efficiently. The roadways were critical roads for ingress and egress to large areas of the County, including for evacuation and emergency response purposes, contributing to the urgency.
Emergency repair plans were developed and a bid opening for the Cavedale Slide Repair Project was held on May 15, 2025. The contract was awarded to low bidder was Gordon N. Ball, Inc. in the amount of $2,308,365, which included a 10% contingency.
During construction, SPI determined that required contract changes were necessary to complete the work, which included accelerated work schedules and field changes, resulting in the total change orders estimated at $919,256. This project is still under construction.
Funding for the original construction project was allocated Tobacco Securitization fund, which is available for use on capital projects. On April 15, 2025, the Board approved an estimated $1,500,000 for Cavedale Road Slide Repair. The estimated total project cost now is $3,545,567. $2,045,567 of additional funding will need to be identified to cover the costs of this project as the project is financed with 100% of local funds. SPI in coordination with the County Executive Office will return to the Board with recommendations for a funding plan.
|
Cavedale Road Project Expenses |
|
Project Service |
Contractor / Supplier |
Award Amount |
Spent |
Additional Expenses |
Total Project Cost |
|
Construction Contract |
Gordon Ball |
$2,308,365 |
$2,158,030 |
$541,970 |
$2,700,000 |
|
Design Contract |
Geo-Logics |
$220,500 |
$202,084 |
$18,416 |
$220,500 |
|
Construction Management Contract |
MNS |
$398,893 |
$65,023 |
$358,870 |
$423,893 |
|
Force Account |
|
$0 |
$176,173 |
$25,000 |
$201,173 |
|
TOTAL |
|
$2,927,758 |
$2,601,310 |
$944,256 |
$3,545,567 |
|
|
|
Tobacco Securitized Funding from 4/15/25 Board Item |
$1,500,000 |
|
Additional Funding Needed |
$2,045,567 |
In summary, in April 2025 the Board approved five storm damage projects for $5,500,000. The total cost to date for these projects is $6,005,729 with additional projected expenses of $1,744,256. Wohler Road and Giovanetti Road Projects have yet to be bid. Additional expenses might be realized for these projects but are not estimated at this stage. Total project costs are estimated at $7,478,331 for the fives storm damaged projects with Westside Road, Cavedale Road Site 2 & 3, and West Soda Rock Road repaired. This leaves a gap in funding of $2,249,985 currently, that will increase when the Wohler Road and Giovanetti Road Projects are put out to bid. SPI will return to the Board in the Spring of 2026 with recommendations for a funding plan to address the funding gap and the two remaining projects: Wohler Road Slide Repair and Giovanetti Road Culvert Improvement.
|
Storm Damaged Projects |
|
Project |
Engineer's Estimate |
Cost to Date |
Additional Expenses |
Total Project Cost |
Funding (Gap) /Surplus |
|
Westside Road |
$1,500,000 |
$2,252,967 |
$800,000 |
$3,052,967 |
($1,552,967) |
|
Cavedale Road Site 2 & 3 |
$1,500,000 |
$2,601,310 |
$944,256 |
$3,545,567 |
($2,045,567) |
|
West Soda Rock Road |
$1,000,000 |
$879,797 |
$0 |
$879,797 |
$120,203 |
|
Wohler Road |
$1,000,000 |
$206,803 |
TBD |
TBD |
$793,197 |
|
Giovanetti Road |
$500,000 |
$64,851 |
TBD |
TBD |
$435,149 |
|
TOTAL |
$5,500,000 |
$6,005,729 |
$1,744,256 |
$7,478,331 |
($2,249,985) |
All Projects
The additional cost for the scope of certain change orders will exceed the delegated authority for Department Head award, triggering approval by the Board. The additional cost of other change orders (Wohler Bridge) will exceed the 10% statutory limit for individual change orders. Changes exceeding the statutory limit ordinarily require competitive bidding, unless competitive bidding would be unavailing and impractical, would not produce any public advantage, and it is in the County’s and public’s best interest to work with the existing contractor on the project rather than competitively bid the project changes. See Graydon v. Pasadena, 104 Cal. App. 3d 631 (1980).
1. The Wohler Bridge change order included new structural work, including modified construction methods in connection with the drilling and pier work, that modifies and is integrated into the original scope that the existing contractor was already mobilized and contracted to perform. The change order includes modifications to what the existing contractor was already constructing, such that it could not be bifurcated and independently performed in conjunction with what that contractor would still be performing. If the change order scope were to be awarded to a separate contractor, then two contractors would be performing essentially the same work at the same time. Having multiple contractors working on the same project gives rise to coordination and management difficulties that are likely to increase the ultimate cost of the project and delay its completion, along with complicating the lines of responsibility for construction delivery and quality.
2. The existing contractor was familiar with the challenges posed by the differing site conditions. Awareness of these site conditions and involvement with the redesigned solutions means that the negotiated price can be relied on to account for all the work needed, with low risk of future change orders due to claims such as unknown conditions or contractor lack of due diligence.
3. Because the Project involves work in the river, there are significant mobilization costs for delivering equipment, materials, and other needed items to the job site. The existing contractor has already incurred these mobilization costs to be in position to perform the change order work, so those are costs that for most part would not have to be re-incurred and again paid by the County. Because any new contractor would have their own new mobilization costs, those costs would likely be included in any new bid, which makes it very unlikely that a new bid amount would be less than the negotiated change order amount.
4. In general, bids for work to be performed during the standard construction season are more competitive (i.e., better priced) when issued during the winter. SPI’s experience and general procurement understanding is that bids issued during the construction season typically have lower participation and higher prices, since most contractors are already underway with existing bids and projects. Any bid for the change order scope would have been unlikely to come in at an amount less expensive than the existing contractor’s quote.
5. If the change order work were competitively bid, the Department would not have been able to accelerate the work to complete the work in the water in a single season. Extending the in-water work to a second season would have significantly escalated costs by triggering new permitting, removal and reconstruction of the in-water work pad, and potential damage to partially completed work that was not designed for winter river flows. As such, having the existing contractor complete the change order work was the most economical way to address the differing site conditions.
By taking the proposed action, the Board is asked to make the following findings, based on the facts set forth above: (1) All of the above statements are true and correct; (2) Competitive bidding of the change order work would not produce an advantage to the County, but would instead increase the cost of the Project, cause delays, and cause avoidable risks to Project management, delivery, quality, and responsibility; and (3) Competitive bidding of the change order work would be undesirable and impractical, and a waiver of competitive bidding is appropriate in this case.
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 1: Continue to maintain road segments, including designated turnouts where feasible, increase efforts on vegetation removal and drainage features, and improve pavement conditions in neighborhoods.
Racial Equity:
Was this item identified as an opportunity to apply the Racial Equity Toolkit?
No
Prior Board Actions:
Wohler Bridge:
2/6/24: Board awarded project construction contract to Ghilotti Construction Company, Inc.
12/07/2021: Board approved Third Amendment to the design contract with Dewberry Engineers, Inc.
5/15/2020: Board adopted an Addendum to the Mitigated Negative Declaration
7/10/2018: Board approved Second Amendment to the design contract with Drake Haglan and Associates, Inc.
5/24/2016: Board approved First Amendment to the design contract with Drake Haglan and Associates, Inc.
11/24/2014: Board adopted a Mitigated Negative Declaration and Mitigation Monitoring Program and approved the Project
9/24/2013: Board approved design contract with Drake Haglan and Associates, Inc.
Westside and Cavedale:
April 15, 2025; Item#19A Authorization to Utilize Road Commissioner Authority for Specified Flood Disaster Projects
Fiscal Summary
|
Expenditures |
FY25-26 Adopted |
FY26-27 Projected |
FY27-28 Projected |
|
Budgeted Expenses |
$3,969,256 |
|
|
|
Additional Appropriation Requested |
|
|
|
|
Total Expenditures |
$3,969,256 |
|
|
|
Funding Sources |
|
|
|
|
General Fund/WA GF |
$1,669,256 |
|
|
|
State/Federal (Wohler Bridge Grant) |
$2,040,100 |
|
|
|
Fees/Other |
|
|
|
|
Use of Fund Balance (Wohler Bridge Local Match) |
$259,900 |
|
|
|
General Fund Contingencies |
|
|
|
|
Total Sources |
$3,969,256 |
|
|
Narrative Explanation of Fiscal Impacts:
Wohler Bridge:
Appropriations for the proposed contract amendment are available in the FY 25-26 Roads Capital (11051--34010103) budget. The project is eligible for 88.7% reimbursement through the Federal Highways Administration (FHWA). SPI has applied for reimbursements of these expenditures but the application has not been approved yet. In the event the application is denied, the Department would use annual allocations from traditional Road funding sources such as Highway User Tax Account (HUTA) or Road Maintenance and Rehabilitation Account (SB1) to pay for the additional contract costs.
Westside and Cavedale:
On April 15, 2025, the Board approved the use of $5,500,000 of Tobacco Securitization (11144-16020700) funds for repair of Westside Avenue, Cavedale Road, West Soda Rock Lane, Wohler Road, and Giovanetti Road. There are sufficient appropriations in the 2025-26 Roads Capital Improvement budget to process payments for these change orders. This Board Item only requests approval of the change order and staff will return to the Board with a recommendation of a funding plan for the gap and projects yet to begin.
Narrative Explanation of Staffing Impacts (If Required):
None.
Attachments:
None.
Related Items “On File” with the Clerk of the Board:
Westside Road Slide Repair Project: Plans, Emergency Construction Agreement
Cavedale Road Slide Repair Project: Plans, Contract
Wohler Bridge Seismic Retrofit Project: Plans, Specifications, Bid Book, Contract Agreement and Amendments with Drake Haglan