Report Prepared by: Joseph D. Angulo, Deputy Director, Public Works
Title
SUBJECT: Approval of a Third Amendment to Professional Services Agreement with Stantec Consulting Services, Inc. for Engineering Design Services for the Wastewater Treatment Facility Phase VI Improvements for an Additional Amount not to Exceed $635,200 and a Total Contract Amount of $2,760,900
REPORT IN BRIEF
Considers authorizing a third amendment to a Professional Services Agreement with Stantec Consulting Services, Inc., for construction phase engineering services of wastewater treatment facility improvement upgrades in an additional amount not to exceed $635,200 and a total contract amount of $2,760,900.
RECOMMENDATION
City Council - Adopt a motion:
A. Approving a Third Amendment to a Professional Services Agreement with Stantec Consulting Services, Inc., in the not to exceed additional amount of $635,200; and,
B. Authorizing the City Manager or the Deputy City Manager to execute the necessary documents.
Body
ALTERNATIVES
1. Approve, as recommended by staff; or,
2. Approve, subject to modifications as conditioned by City Council; or,
3. Refer to staff for reconsideration of specific items; or,
4. Deny.
AUTHORITY
Charter of the City of Merced, Section 200 et seq.
Services with an estimated value greater than $36,000.00 are made by written contract in accordance with Merced Municipal Code, Title 3 - Revenue and Finance, Chapter 3.04.
CITY COUNCIL PRIORITIES
As provided for in the 2022-23 Adopted Budget.
DISCUSSION
Wastewater generated within the City of Merced city limits is processed at the Wastewater Treatment Facility (WWTF), located southwest of the City at 10260 Gove Road. Currently, the City’s WWTF is designed with an approximate capacity in excess of 10 million gallons per day (MGD). In achieving this wastewater flow capacity, the following upgrades were completed:
In 2011, Phase IV upgrades included adding tertiary treatment, a new headworks, a third primary clarifier, and ultra-violet disinfection. These allowed a safe and suitable form of effluent water reuse and discharge to the Hartley Slough sensitive aquatic habitat.
In 2013, the Phase V solids handling project improved the sludge drying practices by diverting digested sludge from earthen drying beds to a modern cement lined active solar drying facility. Centrifuges were installed for biosolids thickening, along with a solids holding tank, methane gas storage capability, a septage receiving station, and other related solids handling facilities.
In 2016, a new laboratory was constructed to improve quality control during the analysis of the treatment plant’s water samples.
Stantec Consulting Services, Inc. Contract
At the June 15, 2020 meeting, Council approved an agreement with Stantec Consulting Services, Inc. (“Stantec”) for a not to exceed amount of $451,900 to evaluate alternatives for cost effective upgrades to achieve a 16 or 20 MGD (million gallons per day) capacity and meet regulatory requirements. Future regulatory items of concern include, but are not limited to: virus disinfection, salinity control, ammonia control, recycled water use, and nitrogen loading to groundwater due to land application of generated waste solids. The contract for the development of the WWTP Phase VI Preliminary Design Report included the following major tasks:
• Evaluate existing water treatment systems and performance;
• Evaluate current and future State Regional Water Quality Control Board regulatory wastewater discharge requirements;
• Evaluate options for improvement and expansion to include methane gas utilization;
• Evaluate costs associated with alternatives;
• Prepare a Preliminary Design Report with select recommendations;
• Assist with a State Revolving Fund application and associated requirements.
First Amendment
At the June 21, 2021, Council meeting, a report presentation was delivered to communicate and discuss the results of the WWTP Phase VI Preliminary Design Report findings. Direction was provided to Staff during the meeting to proceed with the system enhancements. The projects are designed to improve water treatment reliability, enhance biogas utilization, and reduce energy costs. The proposed design elements include improvements to the following:
• Influent Flow Monitor, Influent Pump Station, and Headworks
• Secondary Treatment - Replacement of Reactor Basins 1 & 2
• UV Disinfection System - Recoating of the UV concrete channels
• Sludge Thickening - Upgrade DAFT and replace retention tank
• Solids Dewatering and Drying - Add parallel conveyor and add supplemental heat to active solar dryers
• Septage Receiving Station
• Hybrid Digestion Pilot Testing
Direction was provided to Staff during the meeting to proceed with the design elements as presented for approval. Stantec subsequently prepared a proposal to complete the above tasks and the City Council approved their first contract amendment at the November 1, 2021, meeting. The work is for the not to exceed sum of $1,673,800, bringing the Stantec contact total to $2,125,700.
Second Amendment
The original Stantec contract included an expiration date of June 15, 2022, and an extension was warranted to continue the procured services. Staff requested, and the City Council approved, a Stantec contract extension through project completion. This second contract amendment was approved at the June 6, 2022, meeting and did not involve any cost adjustment to the contract.
Third Amendment Under Consideration
Stantec proceeded to draft design plans for the improvements. The City will soon be issuing the request for bids to complete the following facility improvements: supplemental heat to the active solar dryers, influent flow monitoring, influent pump station, and headworks. The contract amendment under consideration is for: bidding support tasks, bid evaluations, pre-construction and construction meetings, reviewing contractor submittals, conducting special inspections of critical components and upon project milestones, compliance with air pollution control permit activities, startup assistance, updating operation manuals and general project management. The amendment is for the not-to-exceed amount of $635,200, bringing the Stantec contact total to $2,760,900.
The remaining improvements listed above, that are not included in this current bid procurement, are intended to be funded utilizing a loan from the State Revolving Fund, as provided for in the Federal Clean Water Act . Staff will be requesting authorization to apply for these funds at a future meeting.
IMPACT ON CITY RESOURCES
This project was established as a Capital Improvement Project and accounts 553-1108-637.65-00-123035 and 551-1157-637.65-00-123035 contain sufficient funding to complete the project.
ATTACHMENTS
1. Original Contract
2. First Amendment
3. Second Amendment
4. Third Amendment