TO:Andrew P. Powers, City Manager
FROM:Nader Heydari, Public Works Director
DATE:November 4, 2025
SUBJECT: Unit W Wastewater Interceptor Project – Habitat Mitigation Planting (CI 5445)
RECOMMENDATION:
1. Approve the project design, plans, specifications, and Addenda Nos. 1 and 2 for construction of the Hill Canyon Treatment Plant (HCTP) Unit W Wastewater Interceptor Project - Habitat Mitigation Planting (CI 5445).
2. Award construction contract for HCTP Unit W Wastewater Interceptor - Habitat Mitigation Planting (CI 5445) to Dudek, Inc. (Dudek) of Encinitas, CA, in the amount of $691,787.50, plus a contingency of $69,179.
3. Approve Tenth Amendment to Professional Services Agreement (Contract No. 12186-2019) with AECOM Technical Services, Inc. (AECOM) of Bakersfield, CA, for Construction Phase Engineering Support Services on the Unit W Wastewater Interceptor Habitat Mitigation Planting Project (CI 5445) in the amount of $93,664, for a revised not-to-exceed amount of $644,313.
4. Approve Fourth Amendment to Professional Services Agreement (Contract No. 13560-2024) with Padre Associates, Inc. (Padre) of Ventura, CA, for additional Environmental Support and Monitoring Services on the HCTP Unit W Wastewater Interceptor Habitat Mitigation Planting Project (CI 5445) in the amount of $95,240, for a revised not-to-exceed amount of $219,422.62 and extend the term of the agreement to June 30, 2031.
5. Authorize expense in the amount of $949,870.50 ($691,787.50 construction contract, $69,179 construction contract contingency, $93,664 for engineering construction support services, and $95,240 for construction environmental monitoring services) from A/C #624-8250-682-8300 (Wastewater Fund – Capital Improvements, CI 5445).
Unit W Wastewater Interceptor Project – Habitat Mitigation Planting (CI 5445) November 4, 2025
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6. Delegate authority to the City Engineer to approve changes in the design, plans, specifications, and working details of the project on work directives and change orders up to the project-approved contingency amount.
7. California Environmental Quality Act (CEQA): A Mitigated Negative Declaration (MND) was approved for this project by City Council on February 22, 2022.
LEVINE ACT ITEM: Yes
FINANCIAL IMPACT:
No Additional Funding Requested. $1,199,039 in available carryover budget is included in the FY 2025-26 Wastewater Capital Fund for CI 5445. Total project costs are estimated at $6,356,446.
BACKGROUND:
The City’s HCTP provides tertiary-level wastewater treatment for the community. As part of the overall wastewater collection and treatment system, large-diameter wastewater interceptor pipelines were installed to transport the wastewater from the community and deliver it to the HCTP. The Unit W Wastewater Interceptor is a gravity collection pipeline that originates near The Oaks Mall and transports a large volume of wastewater along the Arroyo Conejo Creek to the HCTP (Attachment #1).
The original Unit W pipeline was installed in the 1960s, and improvements have been made over the following decades. In the lower portion of the interceptor, the original 1960s Unit W pipeline consists of a 30-inch diameter pressurized pipeline with two major wastewater access structures (Structure W-1 and Structure W/F).
The structures enable staff to control and access the wastewater interceptors. This CI 5445 project involves important rehabilitation of Unit W, to help prolong the life of current assets and reduce overall risks and maintenance costs to these critical wastewater pipelines.
Environmental Support Services
As part of the regulatory permit process, the California Department of Fish and Wildlife (CDFW) required compensatory mitigation of the impacts associated with the project. These regulatory permits are required due to the environmentally sensitive area of the project and the necessary construction work within the creek channel crossings and banks. In the CDFW permit, compensatory mitigation was required to offset the impacts of the construction project. The habitat/landscape mitigation construction plan consists of planting native plant species in specific areas of the canyon and providing temporary irrigation for these plantings until they are established.
Unit W Wastewater Interceptor Project – Habitat Mitigation Planting (CI 5445) November 4, 2025
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On February 27, 2024, City Council approved a Single-Source Designation and Professional Services Agreement with Padre, in the not-to-exceed amount of $83,468, to prepare the required project regulatory permit applications, as well as perform the environmental analysis for the project impacts, and the CEQA compliant Initial Study/MND. The First Amendment to the agreement was approved by City Council on February 11, 2025, in the amount of $2,805, increasing the not-to-exceed amount to $86,273 for additional environmental and monitoring services and a time extension to December 31, 2025. The Second Amendment was executed using previously approved extra services funds under City Manager authority on July 1, 2025, in the amount of $4,030, increasing the contract amount to $90,303 for the preparation of an Arborist Report. The Third Amendment was approved by City Council on September 23, 2025, in the amount of $33,879.62, increasing the contract amount to $124,182.62, for additional environmental review and monitoring during the construction phase. Padre prepared the required project regulatory permit application packages for the Regional Water Quality Control Board, CDFW, and the U.S. Army Corps of Engineers.
Engineering and Landscape Architecture Services
On August 27, 2019, after a competitive Request for Proposals (RFP) process, City Council approved a Professional Services Agreement with AECOM, a professional engineering firm, for the preparation of an initial asset assessment of the Unit W Pipeline Project. The initial asset assessment was the first part of a larger overall scope of design and engineering work that was included in the RFP, which included a progressive design package release approach, and was thereafter followed by larger and more detailed design and engineering packages.
To date, a total of nine amendments have been processed for progressive releases of design and construction phases, as well as time extensions for a current revised not-to-exceed amount of $550,649, plus extra services of $51,060. In May 2020, the First Amendment was approved as a time extension by the City Manager. The Second Amendment was approved by City Council on January 26, 2021, to add $178,500 for the main design phase services. The Third Amendment was approved in October 2021 by the City Manager to extend the agreement to June 30, 2022. The Fourth Amendment was approved by the City Manager in June 2022 to add $13,249 for additional design services and extend the term of the agreement to June 30, 2023. The Fifth Amendment was approved in May 2023 by the City Manager to extend the agreement to December 31, 2024, due to the need to re-bid the project. The Sixth Amendment was approved by City Council on July 11, 2023, to add $31,000 for value engineering and design modifications for the re-bid. The Seventh Amendment was approved by City Council on February 27, 2024, to add construction phase services in the amount of $133,600 and Unit W Wastewater Interceptor Project – Habitat Mitigation Planting (CI 5445) November 4, 2025
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extend the term of the agreement to December 31, 2025. The Eighth Amendment was approved by City Council on February 11, 2025, to add additional construction phase services in the amount of $46,900. The Ninth Amendment was approved by City Council on April 8, 2025, to add Landscape Architecture Design Services in the amount of $72,400 and extend the term of the agreement to June 30, 2026.
Construction Contract
On February 11, 2025, City Council awarded the construction contract for the main condition assessment phase of the project to Toro Enterprises, Inc. in the amount of $3,440,000. The construction phase of the project began in April 2025, and is expected to be fully completed by December 2025, to be immediately followed by the habitat mitigation planting phase of the project.
The work to be performed for the habitat restoration phase of the project starting in early 2026 includes planting cuttings from native species and applying native seeds to the areas that were impacted by the project’s construction. There are 15 mitigation areas included in the restoration project, with a total planting area encompassing 1.18 acres. Temporary irrigation of the planted areas is also included in the plans and specifications. The project documents include the required five years of maintenance and monitoring of the planted areas (e.g., weeding, watering, replacing dead plant material, etc.) as required by the CDFW permit. The permit requires a specific successful plant survival/coverage rate at the end of the five-year period, which the contractor will be required to meet. Failure to achieve the success rate of the plants at the end of the five-year period will result in extending the mitigation monitoring period.
DISCUSSION/ANALYSIS:
City Council authorized bidding of the habitat restoration work on the project on August 9, 2025, and the Notice Inviting Bids was publicly advertised in the Thousand Oaks Acorn newspaper and posted on the City’s procurement website on September 12, 2025, per the Public Contract Code Section 22037 and Thousand Oaks Municipal Code 3-10.306. Three bids were received and publicly opened on October 8, 2025. The bid results are as follows:
Bidder Bid
1. Valor Construction, Inc. (Newbury Park, CA) $465,550.00
2. Dudek (Encinitas, CA) $691,787.50
3. FS Contractors, Inc. (Sylmar, CA) $695,050.00
The lowest bid received from Valor Construction, Inc. (Valor) was for $465,550; however, Valor’s bid did not include the required number of representative projects Unit W Wastewater Interceptor Project – Habitat Mitigation Planting (CI 5445) November 4, 2025
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(five required) that were of similar scope and complexity, where Bidder’s work on each project was $300,000 or more. As a result, Valor’s bid was determined to be non-responsive. Valor was notified on October 14, 2025, that their bid was deemed non-responsive and would not be considered for award.
The second bid package was submitted by Dudek and has been reviewed and found to be in order. The time for bid protests has expired and no bid protests have been received. There was a clerical error in the Dudek bid where the unit prices were not totaled correctly. When recalculated during the review process, this modified their written bid total from $714,288 to $691,787.50. The sum of the individual unit totals when properly calculated is $691,787.50, which is the corrected bid. Staff reviewed the representative projects that Dudek listed, and all projects meet the requirements of a similar scope and complexity. After reviewing the Dudek bid package, staff recommends the award of the construction contract to Dudek.
Design Support Services During Construction
AECOM is the project landscape architect of record and will provide construction support services required for the project during the habitat mitigation phase.
Construction support services will include responding to requests for information, reviewing material submittals, preparing the final project punch list, and preparing record drawings upon completion. The services will also include periodic attendance at weekly construction meetings throughout the construction period. City staff will be performing the daily observation efforts associated with the planting and seeding work as well as the 5-year monitoring (e.g., proper irrigation, weeding, etc.). Staff recommends approval of the Tenth Amendment to (Contract No. 12186-2019) AECOM for $93,664 (Attachment #2) for a revised not- to-exceed amount of $644,313.
Environmental Support Services During Construction
Padre is the environmental/biological consultant of record and will therefore also provide construction support services required for the project. Padre’s construction support services will include technical oversight to ensure the requirements of the environmental permits from the CDFW streambed alteration agreement and other required CEQA mitigation monitoring requirements for the project are met. Such mitigation and monitoring activities require services in connection with biological monitoring, breeding bird surveys, and permit compliance documentation during and after project construction.
Staff recommends approval of the Fourth Amendment to Contract No. 13560-2024 with Padre for $95,240 (Attachment #3) for a revised not-to-exceed amount of $219,422.62 and to extend the term of the agreement to June 30, 2031.
Unit W Wastewater Interceptor Project – Habitat Mitigation Planting (CI 5445) November 4, 2025
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The estimated overall project cost breakdown is as follows:
Design and Engineering Support w/AECOM (previously approved) $ 297,749 Design and Engineering Extra Services (previously approved) $ 39,170 Engineering & Project Management Support w/Phoenix (prev. approved) $ 125,000 Isolation Valves Equipment (prev. approved) $ 68,129 Unit W Construction Contract w/Toro (prev. approved) $ 3,440,000 Unit W Construction Contingency (prev. approved) $ 344,000 Construction Phase Support Services w/ AECOM (prev. approved) $ 180,500 Habitat Rest. Design Services w/AECOM (prev. approved) $ 72,400 Habitat Rest. Mitig. Design Services Extra Services (prev. approved) $ 7,200 Const. Phase Support Services Extra Services (prev. approved) $ 4,690 Const. Phase Environ. Monitoring w/Padre (prev. approved) $ 83,468 Const. Phase Environ. Monitoring- Amend. 1 w/Padre (prev. approved) $ 2,805 Const. Phase Environ. Monitoring- Amend. 2 w/Padre (prev. approved) $ 4,030 Const. Phase Environ. Monitoring- Amend. 3 w/Padre (prev. approved) $ 33,879.62 City Furnished Supplies and Materials (prev. approved) $ 5,000 Bank Letter of Credit for CDFW Permit Obligations (prev. approved) $ 550,000 Fee for Bank Letter of Credit for CDFW (prev. approved) $ 22,000 Plug Valves Equipment Purchase (prev. approved) $ 126,555 Total Estimated Costs (through Previous Actions) $ 5,406,575.62 Habitat Mitigation Construction Contract w/ Dudek (this action) $ 691,787.50 Habitat Mitigation Construction Contingency w/ Dudek (this action) $ 69,179 Habitat Mitigation Construction Phase Support Services Amend. 10 w/AECOM (this action) $ 93,664
Environmental Support During Const. Amend. 4 w/Padre (this action) $ 95,240 Total Estimated Costs (this action) $ 949,870.50
Total Estimated Project Costs $ 6,356,446.12
This construction phase is anticipated to start by January 2026 and is expected to be fully completed by May 2026. The project design plans, specifications, and Addenda Nos. 1 and 2 are available for review by request to the Public Works Department by e-mail at [email protected] or by phone at (805) 449-2400.
Environmental Review
As required under the provisions set forth in Section 15063 of the State of CEQA Unit W Wastewater Interceptor Project – Habitat Mitigation Planting (CI 5445) November 4, 2025
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Guidelines, an Initial Study was prepared by the City of Thousand Oaks for the Unit W Wastewater Interceptor Improvements Project (CI 5445). The Initial Study evaluated the potential effects of this project on the environment. Although the Initial Study determined the project could have a potentially significant impact on the environment for certain receptors, the project design will reduce the impacts. Furthermore, feasible mitigation measures have been identified that would either avoid or reduce impact to a level of insignificance, or less than significant with mitigation. Based on these findings, an MND and Mitigation Monitoring Reporting Plan was prepared for the proposed project in compliance with the provisions set forth in Section 15070 of the CEQA Guidelines. On February 22, 2022, City Council adopted the construction project MND.
Community Outreach: This project will be limited to work in the lower Arroyo Conejo south fork area and is not expected to impact neighboring residences. The work will be located at the south end of the plant and will have a limited impact on the treatment plant’s operation. Construction-related impacts to hiking trail users are expected to be minimal.
This project meets City Council’s Top Ten Priorities #8 and #9, “Environmental Sustainability” and “Public Works Infrastructure Investments.” CIP PROJECT PRIORITY (as outlined in FY 2025-26 and 2026-27 CIP Program Budget)
Priority Two – Necessary, but not essential, and there could be consequences if deferred.
LEVINE ACT (California Government Code § 84308):
This item is subject to the Levine Act. City Councilmembers who have received a campaign contribution of more than $500 (aggregated) within the preceding 12 months from a party or their agent/representative, or a financially-interested participant involved in this proceeding may do either of the following: (1) disclose the contribution on the record and recuse themselves from this proceeding; or if applicable (2) return the portion of the contribution that exceeds $500 within 30 days from the time the official knew or should have known about the contribution, and participate in the proceeding.
All parties and their agents/representatives must disclose on the record of this proceeding any aggregated contribution of more than $500 made to any Councilmember within the preceding 12 months. Councilmembers are prohibited from accepting, soliciting, or directing a campaign contribution of more than $500 (aggregated) from a party, their agent/representative, or a financially-interested participant during a proceeding and for 12 months following the date a final Unit W Wastewater Interceptor Project – Habitat Mitigation Planting (CI 5445) November 4, 2025
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decision is made. In addition, a party, their agent/representative, or a financially- interested participant is prohibited from contributing more than $500 (aggregated) to a Councilmember during a proceeding and for 12 months following the date a final decision is made. The Levine Act disclosure form for AECOM and Padre have been completed and is included in each of their respective amendments (Attachments Nos. 2 and 3).
COUNCIL GOAL COMPLIANCE:
Meets the following City Council goal:
F. Provide and enhance essential infrastructure to ensure that the goals and policies of the Thousand Oaks General Plan are carried out and the City retains its role and reputation as a leader in protecting the environment and preserving limited natural resources.
PREPARED BY: Paul Weinstein, Associate Analyst
Attachments:
Attachment #1 – Vicinity and Location Maps
Attachment #2 – Tenth Amendment to Contract 12186-2019 with AECOM Attachment #3 – Fourth Amendment to Contract 13560-2024 with Padre Documents Provided Under Separate Cover:
#1 – Project Plans and Specifications
DPW 850-20\ev\Council\2025\110425\CI 5445\Unit W WW Interceptor Habitat Mitigation Planting Plan staff report.docx