City Council
Staff Report
From: City Manager
Report Type: CONSENT CALENDAR
Lead Department: Public Works
Meeting Date: December 11, 2023
Report #:2308-1879
TITLE
Regional Water Quality Control Plant Joint Intercepting Sewer Rehabilitation Project Phase 1:
Approval of Construction Contract, Construction Management Contract Amendment, and Addendum 12 to the Mountain View, Los Altos, and Palo Alto Agreement on Project Funding; CEQA status – Exempt under CEQA Guidelines Section 15301 (Repairs to Existing Facilities)
RECOMMENDATION
Staff recommends that Council:
1) Approve and authorize the City Manager or their designee to execute the contract with SAK Construction, LLC in the amount of $7,347,700 for the Joint Intercepting Sewer Rehabilitation (Phase 1) Project, funded in Wastewater Treatment Enterprise Fund Capital Improvement Program, Project WQ-24000, at the Regional Water Quality Control Plant;
2) Authorize the City Manager or their designee to execute one or more change orders to the contract with SAK Construction, LLC for related, additional but unforeseen work that may develop during the project, the total value of which shall not exceed $734,770 or 10% of the contract amount, for a total not-to-exceed amount of $8,082,470; 3) Approve and authorize the City Manager or their designee to execute Amendment No. 1 to Contract No. C21176592E with Tanner Pacific, Inc. to increase the contract amount by $852,499 to provide construction management and inspection services during construction of the Joint Intercepting Sewer Rehabilitation (Phase 1) Project (CIP WQ- 24000). The revised total contract amount is not to exceed $852,500 including $775,000 for basic services and $77,500 for additional services; and 4) Approve and authorize the City Manager or their designee to execute Addendum No. 12 to the basic agreement between the City of Palo Alto, the City of Mountain View, and the City of Los Altos.
EXECUTIVE SUMMARY
The Joint Intercepting Sewer Rehabilitation (Phase 1) Project will install a structural liner onto the interior surfaces of severely corroded concrete pipe, measuring 2,364 linear feet in length and 72 inches in diameter, near the Regional Water Quality Control Plant. The new liner will extend the life of the sewer pipe and prevent a future collapse of the concrete pipe in the
absence of rehabilitation such as liner installation. Council approval is needed for a construction contract with a specialty contractor, a construction management contract amendment to oversee the contractor’s work, and an Addendum No. 12 to the Basic Agreement with Palo Alto, Mountain View, and Los Altos to repay costs for the construction work in Fiscal Year 2024 and 2025.
BACKGROUND
The Regional Water Quality Control Plant (RWQCP, Plant) owns and maintains a 72-inch diameter trunk sewer known as the Joint Intercepting Sewer, which conveys raw sewage from Mountain View, Los Altos, Los Altos Hills, and a portion of Palo Alto. There are other sewers leading to the RWQCP, but these are maintained by the Utilities Department, Stanford University, and the East Palo Alto Sanitary District.
The Joint Intercepting Sewer was constructed in 1972 and consists of multiple sections of 60- inch and 72-inch diameter reinforced concrete pipes with gasketed bell and spigot joints. The original pipe is unlined with no external coating. The pipes are approximately 9,000 feet long.
The pipeline’s alignment starts at a metering station located at 1151 San Antonio Road on the border of Palo Alto and Mountain View. The alignment runs northwest and below grade through the Baylands Nature Preserve and along the western edge of the City’s closed landfill.
The pipeline ends at an influent junction box inside the RWQCP.
The need for rehabilitation or replacement of the Joint Intercepting Sewer was first identified in the Long Range Facilities Plan (LFRP)1, which was accepted by the Council in July 20122. The need for rehabilitation was confirmed in 2020 via a condition assessment, which included closed circuit television (CCTV) inspection, sonar inspection, and visual inspections of the entire pipe length. Based on the findings, the downstream sections (approximately 2,364 feet) closest to the Plant exhibited the greatest deterioration. The lower section of pipeline has exposed and corroded structural rebar, spalling and cracked concrete, and noticeable offset and separation at some pipe joints and manholes. This Joint Intercepting Sewer Rehabilitation Phase 1 Project will rehabilitate the deteriorated 2,364-feet section of pipeline and manholes. A design contract was awarded to Jacobs Engineering Group, Inc. by Council on May 16, 20223. The design was completed in August 2023.
1 Long Range Facilities Plan for the Regional Water Quality Control Plant, 2012; https://www.cityofpaloalto.org/files/assets/public/public-works/water-quality-control-plant/lrfp-final-report-08- 2012.pdf
2 City Council, July 2, 2012; Consent Item #1; SR #2914, https://www.cityofpaloalto.org/files/assets/public/v/1/agendas-minutes-reports/reports/city-manager-reports- cmrs/year-archive/2012/id-2914.pdf
3 City Council, May 16, 2022; Consent Item #7; SR #14164, https://www.cityofpaloalto.org/files/assets/public/v/1/agendas-minutes-reports/reports/city-manager-reports- cmrs/year-archive/2021/2022/id.-14164.pdf
Based on the 2020 sewer inspection, the upstream sections (approximately 6,600 feet to the metering station) show less severe deterioration and will be reassessed in the next five to ten years to establish the timing and need for the Phase 2 rehabilitation work. Attachment A is a figure showing the project phases.
The Joint Intercepting Sewer’s maximum allocated flow capacity and cost sharing allocation for each partner agency is shown in Table 1 below. Maximum flow capacity is reached during high flow events during wet weather.
Table 1: Maximum Flow Capacity Allocation and Fixed Cost Share Item Mountain View Palo Alto Los Altos Los Altos Hills Total Maximum Allocated Flow
Capacity
(million gallons per day)
50.00 14.59 12.00 3.41 80.0
Allocated Share (percent) 62.50% 18.24% 15.00% 4.26% 100%
ANALYSIS
This Project will rehabilitate approximately 2,364 feet of the 9,000 feet of the Joint Intercepting Sewer from Manhole No. 4 to the Plant’s influent junction box (a.k.a., JB-0). This section of the pipe is shown in Attachment A as the Phase 1 project. Rehabilitation includes repair and recoating the interior of existing manholes and the influent junction box. An above grade temporary bypass pumping system consisting of pumps and piping will be installed in the vicinity of the existing sewer pipeline to allow the contractor to access, clean, inspect, and rehabilitate the interior of the sewer line and manholes. Pipe rehabilitation will use the cured- in-place pipe (CIPP) method, in which a resin-impregnated liner is inserted, expanded, cured, and adhered onto the existing pipe’s interior surfaces. The cured liner will become a new pipe inside the existing host pipe, providing structural strengthening as well as smoother and corrosion resistant surfaces that will not reduce the trunk sewer’s service capacity. Its service life is expected to be extended by 25 to 50 years. This method will result in minimal site disturbance and require the least amount of construction staging area compared to other repair methods such as open trench pipe replacement. The Utilities Department has utilized CIPP lining on City sewers, having rehabilitated approximately 23,025 feet (4.36 miles) of the City’s pipes ranging from 6 inches to 42 inches in diameter.
Construction activities are expected to take place inside the RWQCP (30 percent of the work) and outside the RWQCP (70 percent of the work) along the alignment of the sewer interceptor on small undeveloped areas outside the plant’s fence line and gravel access road west of Byxbee Park. Temporary fencing will be set up along the boundary of the project site.
Construction fences will have six to eight inches of openings at the bottom to allow wildlife to pass through the area. Screening will be attached to project fencing to reduce noise and light outside the construction area. An informational site map showing the URL to the project’s website and detour signs will be set up on trails at appropriate locations. Construction activities lasting up to five months will occur during daytime only and traffic will be limited to material and fuel deliveries. When construction vehicles travel outside of fenced work area, traffic control flaggers will walk ahead and behind each truck to ensure public safety. The contractor’s personnel will be onsite 24/7 to monitor the temporary bypass pumping system, which is expected to last two to four months. The temporary bypass pumps will be enclosed to comply with noise ordinances while pumps and piping will be sealed to contain odors. Illumination, as needed to meet OSHA safety requirements at the bypass pumps, will be soft lights with directional shields and with on/off switches. City staff will coordinate with other projects in the Baylands (e.g., the Horizontal Levee Project) to minimize schedule and parking impacts.
A biological survey was conducted by two qualified biologists from the project’s design consultant, Jacobs Engineering Group, Inc., on March 1, 2023 at the proposed project site and throughout a 250-feet buffer zone beyond the perimeter of the project site. The field survey showed no sensitive habitat within the project site and found that construction activities are not anticipated to directly or indirectly impact adjacent aquatic resources or special-status plants and animals, which were determined to be absent or unlikely to occur within the project footprint. Special-status birds, including salt marsh common yellowthroat, Alameda song sparrow, and burrowing owl, could nest outside and near the project footprint. Preconstruction surveys for nesting birds and burrowing owls will be conducted at 24 days and at 24 hours prior to the start of field construction activities. If active nests are detected, buffers around nests will be established to ensure breeding is not disrupted or adversely impacted by construction. With these measures in place, potential adverse impacts to special status animals will be avoided or minimized.
Bid Process
On August 29, 2023, the City solicited formal bids from qualified contractors for this Project.
The bidding period was 49 calendar days. Three bids were received on October 16, 2023, with bid prices ranging from $7,347,700 to $11,051,740 as listed in the attached Bid Summary (Attachment B).
Table 2: Summary of Invitation for Bids
Project Bid Name/Number Joint Intercepting Sewer Rehabilitation (Phase 1) Project, IFB #189237
Proposed Length of Project 9 months after Notice to Proceed Total Days to Respond to Bid 49
Table 2: Summary of Invitation for Bids
Mandatory Pre-Bid Meeting Yes
Number of Company Attended Pre-Bid Meeting 9
Number of Bids Received: 3
Base Bid and Additive Alternate Price Range $7,347,700 to $11,051,740 Public Link to Solicitation https://procurement.opengov.com/portal/palo-alto- ca/projects/58535/document
Staff has reviewed all bids submitted and recommends the bid of $7,347,700 submitted by SAK Construction, LLC be accepted and SAK Construction, LLC be declared the lowest responsible bidder. The base bid is 7.3% above the engineer's estimate of $6,850,287 and is within the expected level of estimating accuracy. A contingency amount of $734,770 (10% of the bid price) is requested for related, additional but unforeseen work that may develop during the project.
Staff confirmed with the Contractor's State License Board that the contractor has an active license on file. It is recommended that Council approve and authorize the City Manager or their designee to execute the contract with SAK Construction, LLC4.
Construction Management Contract Amendment
The RWQCP capital program requires specialized consultant services to manage the construction and inspection of construction contract work. These services are an extension of staff and essential for providing quality assurance to ensure that: 1) the construction contractor is adhering to the project-specific specifications and contract requirements; and 2) the City is receiving the as-designed infrastructure in an efficient, timely, and coordinated manner.
On June 21, 2021, Council approved five separate five-and-a-half-year contracts (Contract Nos.
C21179265A through C21179265A E) with MNS Engineers, Inc.; CDM Smith; Carollo Engineers, Inc.; MCK Americas, Inc. and Tanner Pacific, Inc. for RWQCP On-Call Construction Management and Inspection Services with a total not-to-exceed amount of $1 for each contract5.
On September 8, 2023, staff requested proposals from all five construction management consultants for Task 4 Services for the Joint Intercepting Sewer Rehabilitation (Phase 1) Project.
No proposals were received initially on October 6, 2023. To ensure timely construction completion, staff reached out to all five consultants to request a proposal by November 7, 2023. The five consultants are experiencing resource constraints due to multiple, ongoing, Bay 4 SAK Construction, LLC., Construction Contract for the Joint Intercepting Sewer Rehabilitation (Phase 1) Project, C24189237; https://www.cityofpaloalto.org/files/assets/public/v/1/public-works/water-quality-control-plant/files- for-staff-reports/joint-intercepting-sewer/c24189237_sak-construction-contract-for-sr1879.pdf 5 City Council, June 21, 2021; Agenda Item #21; SR #12324, https://www.cityofpaloalto.org/files/assets/public/v/2/agendas-minutes-reports/reports/city-manager-reports- cmrs/year-archive/2021/id-12324.pdf
Area construction projects. Furthermore, specialty inspectors are limited for the key tasks of CIPP lining and fusion of high density polyethylene bypass piping. On November 7, 2023, staff received a proposal from Tanner Pacific, Inc. who previously provided construction management and inspection services to the City of Mountain View for their large diameter sewer pipe rehabilitation project, which utilized CIPP technology similar to this project.
Mountain View staff provided positive feedback regarding Tanner Pacific’s construction management services in Mountain View.
Staff recommends that Council approve and authorize the City Manager or their designee to execute Amendment No. 1 to Contract No. C21179265E (Attachment C) with Tanner Pacific, Inc. to: 1) add Task 4 Services to provide construction management and inspectional services during the construction of the Joint Intercepting Sewer Rehabilitation (Phase 1) Project; and 2) increase compensation by $852,499, from $1 to $852,500. A 10% contingency has been included with the requested amount.
Partner Agencies Agreements
The Joint Intercepting Sewer receives flows from Mountain View, Los Altos, Los Altos Hills, and a portion of Palo Alto. Addendum No. 12 (Attachment D) is added to the Basic Agreement between Palo Alto, Mountain View, and Los Altos. Addendum No. 12 was approved by the Cities of Mountain View and Los Altos on December 5, 2023 and November 28, 2023, respectively. The City’s agreement with Los Altos Hills does not require approval for capital improvement projects. Addendum No. 12 covers:
•agreement by all partners to construct the Phase 1 Project by rehabilitating the 72-inch- diameter Joint Intercepting Sewer from Manhole No. 4 to the Influent Junction Box JB-0; •the maximum amount of funding authorized by all partners for the construction of the Joint Intercepting Sewer Rehabilitation Phase 1 Project, including design engineering, construction management, program management, and construction costs; and •agreement by all partners to provide for the sharing of costs associated with this project.
Staff recommends that Council approve Addendum No. 12 (Attachment D) to the basic agreement between the City of Palo Alto, the City of Mountain View, and the City of Los Altos.
After construction commencement, the submittal review process will take three to four months. Construction field activities will be performed during the dry season in 2024 (around mid-April to End of September). Field activities, including mobilization and demobilization, materials procurement, equipment set up and construction work are anticipated to take approximately five months to complete. The Project is expected to achieve substantial completion by September 16, 2024, with final completion by September 30, 2024.
FISCAL/RESOURCE IMPACT
Funding for project construction is available in the FY 2024 Capital Budget (WQ-24000).
Mountain View, Palo Alto, Los Altos, and Los Altos Hills will fund the project in accordance with the percentages shown in Table 3 below.
Table 3: Cost Share
Item Unit Mountain View Palo Alto Los Altos Los Altos Hills Total Trunk Line Cost
Share % 62.50% 18.24% 15.00% 4.26% 100%
Some of the project expense included in the total project cost of $8.9 million is for the work on the RWQCP site described in Bid Item 6 (approximately $1,896,995), and is the responsibility of all six partner agencies, because the RWQCP continues to use the 72-inch Joint Intercepting Sewer to receive and convey the RWQCP plant-wide return flows to the headworks (e.g., from building sewers, clarifier scum overflow, grit washing process drain, etc.). Each partner is contributing to the return flows. As such, the East Palo Alto Sanitary District and Stanford University will also share in project expenses for the in-plant bypass pumping systems, along with Mountain View, Palo Alto, Los Altos, and Los Altos Hills. The specific bid item for in plant sewer bypassing will be split between all partners based on their share of the ongoing pay-as- you-go capital budget. Palo Alto’s share of the onsite bypassing work cost to be shared by all partners is estimated to be about 35% (i.e., about $663,379 of the estimated $1,896,995 expense).
Actual cost share will be calculated after project completion based on wastewater flows and strength contributed by each partner for 2024.
Table 4 shows the estimated total project construction expenses. See Attachment E for a detailed cost breakdown.
Table 4: Not-to-Exceed Construction Expense by Partner Agencies Partner Agency Cost Sharing
Mountain View $5,159,619
Palo Alto $1,947,106
Los Altos $1,262,089
Los Altos Hills $338,516
East Palo Alto Sanitary District $104,904
Stanford University $122,736
Total Not-to-Exceed Construction Expense including 10%
contingency $8,934,970
STAKEHOLDER ENGAGEMENT
This project is part of the RWQCP’s major capital improvement program funded by the City of Palo Alto and its five partner agencies who use the RWQCP for wastewater treatment. The five partner agencies are regularly updated on both the need for and the progress of wastewater treatment capital work. Updates are provided each year at an annual meeting and at other periodic meetings established to inform partner agency staff about the major capital improvement program. With respect to Palo Alto itself, the open meetings on the budget process serve as the main vehicle for engaging the community on both new projects such as this and associated rate impacts.
Staff reached out to Mountain View, Los Altos, and Los Altos Hills staff to explain the project and cost allocation. Mountain View completed CIPP relining work on a 42-inch diameter sanitary sewer near Shoreline Park in March 2022. Given Mountain View’s experience, staff conducted outreach with Mountain View’s engineering and operational staff to understand key issues associated with CIPP installation in a public park.
In addition, staff has coordinated with the Community Services Department and other Public Works Department staff to coordinate construction activities, bypass pumping, access, and trail detours in parkland and at the closed landfill. On February 28, 2023, staff presented the project to the City’s Parks and Recreation Commission6. Recommendations received from the commissioners were incorporated into the project’s contract documents.
ENVIRONMENTAL REVIEW
The construction of this project has been determined to be exempt from CEQA under CEQA Guidelines Section 15301, subsection (b) as it involves the repair and maintenance of an existing publicly-owned utility used to provide sewerage treatment services with no expansion on the existing facility. A Notice of Exemption was submitted to and recorded by the State Clearing House and Santa Clara County Clerk-Recorder’s Office on August 7, 2023 (File No.
ENV24700).
6 Parks and Recreation Commission, February 28, 2023; Agenda Item #4; https://www.cityofpaloalto.org/Departments/Community-Services/Other-Services/Commissions/Parks-and- Recreation-Commission/PRC-Current-Year-Agendas-and-Minutes
ATTACHMENTS
Attachment A: Site Map Showing the Project Phases
Attachment B: Bid Summary
Attachment C: Amendment No. 1 to Contract C21179265E with Tanner Pacific, Inc. for Construction Management and Inspection Services
Attachment D: Addendum No.12 to the Basic Agreement between the City of Palo Alto, the City of Mountain View, and the City of Los Altos
Attachment E: Partner Agencies Cost Share Summary
APPROVED BY:
Brad Eggleston, Director Public Works/City Engineer