TO:Andrew P. Powers, City Manager
FROM:Clifford G. Finley, Public Works Director
DATE:February 27, 2024
SUBJECT: Public Emergency Declaration - Wastewater Line Repair at Hill Canyon Treatment Plant
RECOMMENDATION:
1. Ratify Public Emergency Declaration by City Manager on February 14, 2024, pursuant to Thousand Oaks Municipal Code (TOMC) 3-10.308 (requires four-fifths vote).
2. Pursuant to Public Emergency Declaration, waive formal bid process set forth in TOMC 3-10.305.
3. Authorize City Manager to approve General Services Agreement with Blois Construction (Oxnard, CA) in an amount not to exceed $125,000.
4. Authorize City Manager to approve General Services Agreement with GSE Construction (Livermore, CA) in an amount not to exceed $50,000.
5. Authorize expense in an amount not to exceed $175,000 for FY 2023-24 from A/C #621-8250-682-5699 (Wastewater Fund – Contracted Services).
6. Find that the Project is categorically exempt from the California Environmental Quality Act (CEQA) pursuant to 14 CCR 15301.
FINANCIAL IMPACT:
No Additional Funding Requested. $175,000 is included in the Adopted FY 2023-24 Wastewater Fund Budget.
BACKGROUND:
The Hill Canyon Treatment Plant (HCTP) treats wastewater from the community of Thousand Oaks. Since the 1960s, HCTP provides advanced tertiary-level wastewater treatment. HCTP treats an average of eight million gallons per day of wastewater generated from domestic, commercial, and industrial sources, operating 24 hours per day, 365 days per year.
Public Emergency Declaration - Wastewater Line Repair at HCTP February 27, 2024
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7 On Sunday, February 11, 2024, at approximately 12:30 a.m., staff observed untreated wastewater leaking from a failed Gravity Belt Thickener filtrate line located at the bridge near the main entrance inside the HCTP. Staff was able to determine the source, stop and isolate the leak within 15 minutes, and report the incident to the Superintendent and Laboratory Supervisor who provided immediate response and began their investigation. Staff determined that the leak started at approximately 11:40 p.m. Saturday night, resulting in an estimated 15,000 gallons of untreated wastewater entering the North Fork of the Arroyo Conejo Creek.
Regulatory agencies were notified as required by HCTP’s National Pollutant Discharge Elimination System (NPDES) permit and according to the HCTP Emergency Response Plan for Wastewater-Related Spills and/or Permit Exceedance. Additionally, Camrosa Water District was also notified because their creek diversion structure for non-potable re-use is downstream of the plant, as well as Conejo Recreation and Park District staff as a courtesy for potential inquiries from hikers. The following morning, City staff posted signage along the creek to alert hikers of the spill. Samples from the creek were collected for testing and analysis. In coordination with Ventura County Environmental Health Division, signage was authorized for removal after three consecutive days of sampling indicated the spill was no longer impacting the creek.
DISCUSSION/ANALYSIS:
The failed pipe is near the center of the roadway just inside the main gate of HCTP and directly adjacent to the main bridge (Attachment #1). This roadway serves as the only vehicular access into HCTP, including trucking and deliveries necessary for plant operations. At the same location of the failed filtrate line are a large number of other utilities and additional process lines. Due to the location of the failed line, staff recognized the potential that the roadway was undermined or could lead to the development of a sinkhole, potentially compromising safe access to the facility or impairing other infrastructure necessary for continued treatment operations. A significant rain event was in the near forecast adding to the urgency for repair.
Staff installed a temporary bypass to send the filtrate flow to another part of HCTP while the affected line was out of service. However, the forecasted rains had the potential to interrupt the use of this bypass line, thus interrupting an integral part of the treatment process.
TOMC Section 3-10.308 provides the City Manager with the authority to declare a Public Emergency, subject to confirmation of the City Council by a four-fifths vote at its next meeting. This allows normal public bidding procedures to be waived when emergency repairs or replacements are necessary to permit the continued Public Emergency Declaration - Wastewater Line Repair at HCTP February 27, 2024
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7 conduct of City operation of services or avoid danger to life or property. Due to the potential safety risks, and to avoid process interruption or further environmental impact to the creek, City Manager approved the emergency declaration to authorize available contractors to initiate repairs on February 14, 2024 (Attachment #2).
Staff contacted multiple contractors to assess availability for repairs. Discussions with contractors revealed that different phases of the repair would need to be performed by different contractors. Staff authorized GSE Construction to temporarily stabilize the impacted area, excavate, and initiate repair of the line. Staff authorized Blois Construction to initiate clearing the line from end to end.
Due to the design, function, and length of the existing line, this includes using specialized equipment to clear and remove build-up and debris at multiple locations, and through multiple passes of the line. Clearing the line will ensure that once repaired, the affected line will be restored to full functionality. Blois Construction and GSE Construction are experienced in this type of work and were available to immediately mobilize. Each contractor will charge on a time and materials basis.
The total cost of this repair was initially estimated at $75,000. However, much of the repair work must be done after-hours due to the location near the main service entrance to the facility, and clearing the line is more complex than originally anticipated. Staff has therefore revised the total not-to-exceed cost estimate to $175,000.
Staff recommends City Council ratify the City Manager’s Public Emergency Declaration, waive the formal bid process, and authorize City Manager approval of two separate agreements with Blois Construction for an amount not to exceed $125,000, and GSE Construction for an amount not to exceed $50,000.
This project is categorically exempt from CEQA per Section 15301 (repair/maintenance of an existing facility).
Community Outreach: This project will be limited to work at the HCTP and is not expected to impact any neighboring residences. The work will occur at the southwest end of the plant. Construction-related impacts to hiking trail users will be minimal.
This project meets City Council’s Top Ten Priorities #6, “Public Works + Infrastructure Investments.”
Public Emergency Declaration - Wastewater Line Repair at HCTP February 27, 2024
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7 COUNCIL GOAL COMPLIANCE:
Meets the following City Council goals:
C. Operate City government in a fiscally and managerially responsible and prudent manner to ensure that the City of Thousand Oaks remains one of California's most desirable places to live, work, visit, recreate, and raise a family.
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: Kim Sherman, Sr. Purchasing Specialist
Tim Mooney, Wastewater Treatment Plant Superintendent
Attachments:
Attachment #1 – Aerial View and Project Drawing
Attachment #2 – Public Emergency Declaration
DPW:1030-35\ev\Council\2024\022724\Public Emergency Declaration WW Line Repair at HCTP staff report.docx