CITY COUNCIL AGENDA ITEM
ACTION REQUESTED:
title
Approve the award of Change Order #1 to Contract 25-074, Field Services for Tollway Substation Transformers, to Transfluid Services, Inc. for an amount not to exceed $14,500 and a total award of $312,269
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DEPARTMENT: Electric Utility
SUBMITTED BY: Raheel Arshed, Deputy Director
BOARD/COMMISSION REVIEW:
N/A
BACKGROUND:
The Electric Utility (Utility) is responsible for maintaining electric service to approximately 63,000 residential and commercial customers. A key component of the 16 electrical substations is transformers that step the 138kV transmission voltage down to lower voltages. At the Tollway Substation (Tollway), the Utility owned a transformer referred to as 30XA, which failed in September of 2024. This transformer was built in 1971 and was responsible for stepping down voltage from 138kV to 34.5kV and 12.47kV, respectively.
In June 2025, the City Council awarded Contract 25-074, Field Services for Tollway Substation Transformers, to return the system to normal configuration. This project included moving an underutilized “sister” transformer known as 10XA, also built in 1971, from the Westside Substation (Westside) to Tollway. Moving 10XA from Westside to Tollway was essentially a like-for-like replacement, restoring Tollway to pre-failure conditions.
The Westside transformer vacancy was filled with a spare transformer stored at the Route 59 Substation. The spare transformer placement at Westside restored the 12kV system to normal, while abandoning the rarely used 34kV source at Westside. While not a like-for-like replacement, commissioning the spare transformer at Westside restores normal functionality to the substation. The spare transformer will be replaced with the one that was procured in June of 2025, and will take approximately 30 months to build.
DISCUSSION:
Change Order #1 is requested to address unforeseen field conditions that could not have been reasonably identified before the project began. The process of relocating a substation transformer of this size involves removing approximately 14,000 gallons of insulation oil from the unit. The oil is moved separately in a tanker. After the transformer is reset at the new location, a vacuum is applied to the tank of the transformer to both remove any moisture that may have gotten into the unit and also to test all gaskets for potential leaks.
During the vacuum drying process, a pinhole leak was discovered within one of the transformer’s oil pumps, specifically at an internal interface that is not visible or detectable through standard pre-move inspections. As such, this condition was not included in the original bid specifications.
Resolution of this issue was necessary to ensure the safe and reliable operation of the transformer upon the return to service, and to avoid a future oil leak that would have resulted in having to drain all the oil back out of the unit.
Due to project schedule constraints, repairing or rebuilding the pump was not feasible. Instead, the pump was removed, and the associated opening were securely plated.
The corrective work required an additional two days of labor. The costs associated with this Change Order are directly attributable to the unforeseen condition and reflect reasonable compensation for the added scope of work.
City staff have reviewed the proposed Change Order and recommend approval.
Contract Award
|
Original Contract Value |
$297,763.00 |
|
Prior Cumulative Approved Change Orders |
$0 |
|
Subtotal |
$297,763.00 |
|
(+/-) This Change Order |
$14,500.00 |
|
Total Contract Value |
$312,269.00 |
FISCAL IMPACT:
CIP #: EU022
Field services for substation transformers are expensed to the Infrastructure account listed below. These services are being performed under EU022, the Substation Emergency Repairs and Replacements program. The Electric Utility included $1,224,000 for expenses related to EU022 in 2026. The change order requested is within the amount budgeted for this expense.
|
Account Number |
Fund Description |
Total Budget Amount |
|
40251300-551502 |
Electric Utility Fund |
$25,151,000 |