To: Sonoma County Board of Supervisors
Department or Agency Name(s): Public Infrastructure (SPI)
Staff Name and Phone Number: Johannes J. Hoevertsz, 707-565-2550
Vote Requirement: Majority
Supervisorial District(s): Second
Title:
Title
Structural Repairs to the Sonoma Mountain Communications Tower
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Recommended Action:
Recommended action
A) Approve plans and specifications for the Sonoma Mountain Communications Tower repair project.
B) Award a construction contract to AJM General Construction, in the amount of $198,000, for the subject Project; authorize a contingency up to 25% ($49,500) for the Project; and authorize the Director of Public Infrastructure to execute said construction contract and any other related, required documents, in form approved by County Counsel.
(Second District)
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Executive Summary:
A recent inspection report identified several structural deficiencies with the County owned Sonoma Mountain Communications Tower. The Sonoma Mountain Communications Tower is a fifty (50) year old tower which is a critical main hub in the County’s communications network and the inspection report documents several structural issues including:
1. Rust and corrosion of the structural steel cross-brace members and the climbing appurtenances.
2. The tower guy wires have reached end of useful life and are due for replacement.
3. Need to excavate and inspect guy wire anchor structures.
Sonoma County Public Infrastructure (SPI) staff recommends that the Board award a construction contract to AJM General Construction for necessary repairs to the facility. The proposed contract is for $198,000, and a 25% contingency ($49,500) is recommended.
Discussion:
The Sonoma County Sheriff’s Office maintains a network of communications sites throughout the County and each tower is inspected periodically to confirm the structural integrity of the towers is maintained. On January 24, 2023, the County completed a periodic inspection of the Sonoma Mountain tower.
The inspection, performed by a licensed professional engineer, resulted in a report that identified rust and corrosion on many structural cross-brace steel members on the tower. The rust conditions are affecting approximately 320 steel members on the 185’ high tower and have advanced to a degree that now necessitates corrective action. Remediation of the rust conditions range from simple wire-brushing and recoating of surfaces to complete removal and replacement of individual cross-brace steel members. The report also recommended replacement of the three-level guy wire support system because the cables have reached the end of their usable life, as well as excavation and inspection of the “dead men” anchors. Inspection of the anchors was not possible in January as they are located approximately ten (10) feet below grade.
The Sonoma Mountain Communications Site is a critical main hub in the County’s emergency communications network. All remaining twenty (20) communication towers depend on Sonoma Mountain for effective emergency readiness and continuity of operations. The project was released for bidding on June 26, 2023, and only one bid was subsequently received from AJM General Construction. The bid was evaluated by the County’s Evaluation Committee and determined to be compliant to the RFP and satisfied all evaluation criteria. The respondent bid was evaluated for experience with similar projects and refences provided were contacted. The respondent firm provided three (3) projects of a similar nature and references confirmed that AJM General Construction performed to a high level of satisfaction.
Based on the critical nature of this site, as well as the results of the inspection report, SPI staff is recommending approval of a construction contract to AJM General Construction in the amount of $198,000 plus a 25% contingency of $49,500. The contingency for the project is higher than usual due to the potentially unforeseen circumstances based on the height of the tower and the foundation for the guywires.
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 2: Invest in capital systems to ensure continuity of operations and disaster response.
Objective: Objective 1: Strengthen critical communications infrastructure, interoperability, and information technology tools relied upon during disasters.
Racial Equity:
Was this item identified as an opportunity to apply the Racial Equity Toolkit?
No
Prior Board Actions:
6/16/2023 - Adopted capital project budget for FY 23-24 to expend $717,000 to repair (and/or replace) Sonoma Mtn. 185’ radio tower.
Fiscal Summary
|
Expenditures |
FY 23-24 Adopted |
FY24-25 Projected |
FY 25-26 Projected |
|
Budgeted Expenses |
$247,500 |
|
|
|
Additional Appropriation Requested |
|
|
|
|
Total Expenditures |
$247,500 |
|
|
|
Funding Sources |
|
|
|
|
General Fund/WA GF |
$247,500 |
|
|
|
State/Federal |
|
|
|
|
Fees/Other |
|
|
|
|
Use of Fund Balance |
|
|
|
|
Contingencies |
|
|
|
|
Total Sources |
$247,500 |
|
|
Narrative Explanation of Fiscal Impacts:
Funding for the project in the amount of $717,000 was approved in the FY 2023-24 adopted Communications Towers capital project budget (40801900). $247,500 of those funds will be for proposed contract with the remainder for further repairs to the tower if needed.
Narrative Explanation of Staffing Impacts (If Required):
None.
Attachments:
1-Plans and specifications
2-Construction contract
Related Items “On File” with the Clerk of the Board:
None.