COMMITTEE AGENDA MEMORANDUM
Capital Improvement Program Committee
Government Code § 84308 Applies: Yes ☒ No ☐
(If “YES” Complete Attachment A - Gov. Code § 84308)
SUBJECT: title
Receive Information on Change Orders to Anderson Dam Tunnel Project Construction Contract.
End
RECOMMENDATION: Recommendation
Receive information on change orders to Anderson Dam Tunnel Project Construction Contract.
Body
SUMMARY:
During the May 17, 2021, Capital Improvement Program (CIP) Committee meeting, staff provided an update on the Anderson Dam Tunnel Project (ADTP) No. 91864006. The Committee requested staff provide monthly change order status updates after construction of the ADTP commences on July 7, 2021.
Project Background
Santa Clara Valley Water District (Valley Water) is undertaking the Anderson Dam Federal Energy Regulatory Commission Order Compliance Project (FOCP) as a result of the February 20, 2020, directive from the Federal Energy Regulatory Commission (FERC) to implement interim risk reduction measures at Anderson Dam. One of those measures is the ADTP.
On April 27, 2021, Valley Water’s Board of Directors awarded the construction contract for the ADTP to the top-ranked, best-value proposer, Flatiron Dragados West, Inc. (FDW), in the sum of $161,140,321 and approved a contingency amount of $40,000,000 (25% of the contract price). The Board directed staff to discuss delegating authority for contingency expenditures with the CIP Committee. On January 28, 2025, the Board of Directors approved an increase of $40,000,000 to the construction contract contingency sum, bringing the total construction contract contingency to $80,000,000.
By unanimous roll call vote at its May 17, 2021, meeting, the Committee approved recommending to the full Board that it consider delegating authority to staff to approve change orders for the ADTP at the amounts stated below and that the CIP Committee receive regular monthly reports with information regarding approved change orders, pending change orders, and the cumulative amounts. Valley Water’s Board of Directors accepted the CIP Committee recommendations at its regular meeting on May 25, 2021.
Delegated Approval Authority
Unit Manager: Up to $100,000
Assistant Operating Officer: Up to $250,000
Deputy Operating Officer: Up to $500,000
Assistant Chief Executive Officer: Up to $2.5 million
Chief Executive Officer: Up to $5 million
Board of Directors: $5 million and above
Construction Contract Change Orders Status
There is one new Contract Change Order (CCO No. 60) to present to the CIP Committee. The amount of CCO No. 60 is estimated at $1,700,000.00. Two attachments, providing information on construction contract change orders (Attachment 1) and construction contract financials (Attachment 2), are included for reference.
Contract Change Order No. 60
1. Transition Zone Pipe Extension and Contraction Zone. Valley Water issued Contract Document Clarification (CDC) 048 to replace parts of the final reinforced concrete lining in the tunnel with steel pipes and Lightweight Cellular Concrete (LCC) backfill to mitigate schedule risk and cost impacts for the future Anderson Dam Seismic Retrofit Project (ADSRP). During ADRSP, a portion of the diversion tunnel lining being constructed as part of ADTP will be removed and replaced to accommodate the final outlet works configuration. Therefore, this change will eliminate the need to demolish heavily reinforced concrete lining and articulated joint segments during the construction of ADSRP which will reduce the critical construction sequence schedule to convert the diversion tunnel to the final outlet works.
Implementing these changes is expected to save both time and cost by simplifying the current diversion system construction and future lining removal in the transition zone. The transition zone is the section of the tunnel that becomes reconfigured to convert the diversion tunnel into the final low-level outlet works. Specifically, this design change replaces 74 linear feet of reinforce concrete tunnel final lining with 74 feet of 156-inch diameter steel pipe encased in low-density cellular concrete (LCC).
Previous Contract Change Order 038 was executed to cover the material cost for fabrication and delivery of the 156-inch diameter steel pipe. Given the long lead time required for manufacturing steel pipe of this size, CCO 038 was processed early to ensure the material would be procured and delivered on schedule, avoiding potential delays to the project timeline.
This Contract Change Order addresses the installation portion for the 156-inch diameter pipe extension within the transition zone. The installation work includes the use of rolling frames for moving pipe sections through the tunnel and into their final position, constructing and placing temporary pipe supports and tie-downs, welding 1-inch thick steel pipes, encasing the steel pipes with over 1,300 cubic yards of LCC over multiple shifts to allow for curing before placing subsequent lifts, and constructing a shotcrete contraction zone to provide a transition between the pipe and the tunnel lining. This portion of the change is estimated at $1,700,000.00.
Other Changes from Previous Month Contract Change Order Status
1. No other changes to report from previous month Contract Change Order status.
ENVIRONMENTAL JUSTICE IMPACT:
There are no environmental justice impacts associated with this item.
ATTACHMENTS:
Attachment A - Gov. Code § 84308: Flatiron Dragados West
Attachment 1: Construction Contract Change Orders Status
Attachment 2: Construction Contract Financial Status
UNCLASSIFIED MANAGER:
Manager
Ryan McCarter, 408-630-2983