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HomeMy WebLinkAbout05. Amend agreement with Stantec Consulting for design of Filter Plant and Clearwell Improvements, Phase 1A, DP 7361 Page 1 of 16 Item 5. CENTRAL SAN BOARD OF DIRECTORS vie . , Hill. , , . . POSITION PAPER MEETING DATE: OCTOBER 17, 2019 SUBJECT: AUTHORIZE THE GENERAL MANAGER TO AMEND AN EXISTING PROFESSIONAL ENGINEERING SERVICES AGREEMENT WITH STANTEC CONSULTING SERVICES, INC. TO INCREASE THE AGREEMENT CEILING FROM $1,540,000 TO $3,078,000 FOR FINAL DESIGN OF THE FILTER PLANTAND CLEARWELL IMPROVEMENTS — PHASE 1A, DISTRICT PROJECT 7361 SUBMITTED BY: INITIATING DEPARTMENT: CHATHURAABEYRATHNA, ASSOCIATE ENGINEERING AND TECHNICAL SERVICES- ENGINEER CAPITAL PROJECTS REVIEWED BY: CRAIG MIZUTANI, SENIOR ENGINEER EDGAR J. LOPEZ, CAPITAL PROJECTS DIVISION MANAGER JEAN-MARC PETIT, DIRECTOR OF ENGINEERING AND TECHNICAL SERVICES Roger S. Bailey General Manager ISSUE Board of Directors' (Board) authorization is required for the General Manager to execute an amendment to a professional engineering services agreement above ten percent or$200,000, whichever is greater. BACKGROUND Central San's recycled water facilities have provided a reliable supply of recycled water to Central San's wastewater treatment plant (plant) since being commissioned in 1977. In the mid-1990s, Central San modified these facilities to produce California Title 22 Water Quality Requirements for Recycled Water (Title 22) and delivery to off-site customers in Zone 1, which was defined under an agreement with Contra Costa Water District (CCWD). October 17, 2019 Regular Board Meeting Agenda Packet- Page 25 of 82 Page 2 of 16 While Central San remains the largest customer of the Recycled Water Program, some of the recycled water facilities are nearing the end of their useful lives, which is leading to reliability concerns and the need to address the critical elements of the Filter Plant and Clearwell Improvements project to proceed at this time. Several recent failures, described below, have shaped and focused staff's recommendations for this first phase of the project, entitled Phase 1 A. The east Clearwell cover experienced some failures in 2017. 1 n 2018, a high-voltage (12kV) electrical feeder from Substation 82 (Central San's main PG&E electrical service)to Substation 40 at the Filter Plant failed at a splice box. I n early 2019, Substation 40 experienced another failure which triggered a cascading series of events that led to a 16-minute, plant- wide power failure. The cover ripped in J my 2019, leading to the east cell decommissioning. Recycled water storage is now accomplished in the west Clearwell, which was recently cleaned, commissioned with a temporary cover, and placed in operation. These incidents reflect that, despite staff's good operation and maintenance practices, the recycled water facilities are showing signs of significant deterioration, which is starting to impact reliability. Project History:A Phased Approach with Future Recycled Water Projects On May 3, 2018, the Board authorized an agreement with Stantec Consulting Services, Inc. (Stantec)to provide planning and preliminary design of the Filter Plant and Clearwell Improvements, District Project 7361. As part of this agreement, Stantec prepared several technical memoranda that reviewed the condition of the filter plant, disinfection alternatives, hydraulics, seismic assessment, process and automation, and alternative filtration technologies. Staff and Stantec have taken a long-term approach on this project and have evaluated the possible impacts of future projects, including the Concord Community Reuse Project and especially the Water Exchange Project. When looking at possible solutions to resolve the aging infrastructure needs for the recycled water facilities, the team evaluated Central San's immediate needs, which include the most critical items that require replacement to restore reliability over the next five to ten years, and that would not conflict with or potentially leave stranded assets when the Water Exchange Project is implemented. Staff asked the question: If we knew today that a Water Exchange Project was proceeding, would our recommendation be different? With that thought in mind, staff developed a recommendation that divides the Filter Plant and Clearwell Improvements into three phases, with the most operationally critical elements proceeding first. • Phase 1 A: Electrical improvements, recycled water storage tanks, Clearwell pump renovation, and rehabilitation of one of the four existing filters. • Phase 1 B: Rehabilitation of the remaining three filters and Filter Building, other remaining electrical improvements, upgrades to the Applied Water Pump Station and hydraulic improvements to bypass the Forebays. This phase would also include the addition of a chlorine contact basin and would complete the remainder of the renovations to meet the long-term needs of the Recycled Water Program. • Phase 2: Improvements to provide additional recycled water supply to CCW D so they can serve the future Concord Community Reuse Project. (The Phase 2 project, and its associated costs, is not currently included in the Ten-Year Capital Improvement Plan and budget.) On May 2, 2019, the Board approved an amendment to the agreement with Stantec to complete the 30- percent design for the Phase 1 A project. Shortly thereafter, on June 21, 2019, Central San staff held a Technical Peer Review Treatment Train October 17, 2019 Regular Board Meeting Agenda Packet- Page 26 of 82 Page 3 of 16 Workshop for the Water Exchange Project. The purpose of the workshop was to seek input from technical experts in the consulting and academic communities on the most optimal treatment train that could produce both Central San's current and future Title 22 recycled water supply, in addition to refinery-quality recycled water, while considering Central San's future nutrient removal requirements. There were 32 people in attendance, including Central San staff, Dr. Glen Daigger(University of Michigan), Dr. David Jenkins (Professor Emeritus, UC Berkeley), the lead technologists from twelve major wastewater consulting firms, and representatives of our partner agencies (CCWD and Valley Water). The outcome of the workshop was a number of proposed treatment alternatives. Some of the proposed treatment alternatives included continuing to incorporate process elements of the Filter Plant; possibly repurposing some of the structures (e.g. Forebays and Filter boxes); or completely abandoning the Filter Plant and replacing it with membrane technology. However, under all these alternatives, the need to store and distribute the recycled water to the end users (Central San and Zone 1) remained unaltered. This review of the potential synergy between current and future recycled water related projects further confirmed the decision to divide the project into phases and proceed with the Phase 1 A project. Phase IA Project Staff recommends moving forward with Phase 1 A, which focuses primarily on providing reliable recycled water storage and distribution to end users. The Phase 1 A project will serve the recycled water facilities whether or not the future Water Exchange Project is implemented. Phase 1 A would address recycled water supply reliability (e.g. storage and pumping) and address electrical safety and deficiency concerns. n addition, it will include rehabilitating one of the four existing filters. This filter rehabilitation would have a dual purpose: reliability of production (worst operating filter) and provide the filtration production capacity needed to meet current demand using new filter media. Central San will benefit from the new filter for a minimum of five to ten years before the Water Exchange Project is implemented. A more detailed scope of work for Phase 1 A is provided in Attachment 1. Business Case Evaluations (BCEs) Central San performs comprehensive BCEs for every capital project, which includes, but is not limited to, the following tasks: • Evaluate specific project needs and drivers. • Conduct an in-depth evaluation of existing asset condition assessment(s) and determination of remaining life. • Evaluate whether to keep the existing assets or replace with in-kind and/or new technology. • Evaluate current and possible future regulatory drivers or related projects that would impact the project solutions. • Preliminary investigation as needed (geotechnical, permitting, environmental, etc.). • Prepare alternative solutions, which consists of: prepare and estimate costs and related expenditures; evaluate operations and maintenance impacts; compare pros and cons; and prepare lifecycle cost analysis for each alternative. • Prioritize scope or projects based on multiple factors. Sometimes, this may require phasing a project over time or combining projects into one project. • Conduct pilot testing of preferred technology when appropriate to validate design criteria and risk (i.e. Filter pilot testing completed under Phase 1 A). • Review and discuss with the Capital I mprovement Program Executive Review Committee (Executive Team) and stakeholders. October 17, 2019 Regular Board Meeting Agenda Packet- Page 27 of 82 Page 4 of 16 Since the last Board update, two BCEs were conducted. The BCEs include disinfection and recycled water storage. Staff recommends postponing the chlorine contact basin and building two new steel storage tanks. Details of these BCEs can be reviewed in Attachment 2. At the request of the Engineering and Operations Committee, alternative RW S-6 was evaluated to determine if constructing the new storage tanks with cast-in-place reinforced concrete with a common divider wall would be more cost effective than the recommended alternative RWS-3: Provide two new storage tanks using above-ground steel. This BCE alternative was evaluated by the design team and determined to be more expensive than the recommended alternative. California Environmental Quality Act(CEQA): At its May 2, 2019 meeting, the Board independently found that the agreement with this vendor (Stantec) was exempt from CEQA under Central San's CEQA Guidelines Section 15262, since it allowed for further planning and feasibility studies for possible future actions which Central San has not approved, adopted, or funded, and the outcome of these tasks will not have a legally binding effect on later activities. Central San will conduct an environmental evaluation of any capital project that is proposed in the future as a result of the tasks authorized herein to determine the need for any additional CEQA documentation. ALTERNATIVES/CONSIDERATIONS Other alternatives are set forth below; however, are not recommended by staff. Alternative 1: Split Phase 1 A into smaller projects and spread the construction over several fiscal years. While this approach would result in a smaller initial design fee request, administering separate smaller projects within the same work areas, possibly with overlapping schedules, would be more challenging in terms of coordination between the designs and potentially multiple contractors, thereby increasing the overall cost of the project. This alternative would result in higher costs due to the added overhead, cost of bidding and administering separate projects, staff coordination, and costs for keeping the facility operational during construction. Alternative 2: Delay recommended project elements longer or minimize scope and wait to integrate the solutions to the current problems with the Water Exchange Project. Under this alternative, staff would proceed with a smaller scope project and postpone some of the needed work to the future, if possible. All elements suggested as part of Phase 1 A are deemed critical for the reliable operation of the recycled water facilities and required in the next five years, with electrical and storage needed sooner. The only scope item that may be considered for postponing is rehabilitating one filter; however, staff is proposing to list this work as a bid alternate and consider the rehabilitation after receiving the bid. Alternative 3: Do nothing to the facilities. Under this alternative, staff would not amend Stantec's agreement and the existing recycled water facilities would continue operating in its current condition. Repair of facilities would be done upon failure. This alternative would prevent staff from implementing work that will maintain a reliable recycled water supply to both Central San's plant and Zone 1 customers. FINANCIAL IMPACTS The total anticipated cost for final design for Phase 1A is $1,538,000, which includes design and bidding services performed by Stantec. The current Stantec agreement is valued at$1,540,000 and if the final design is included would result in an agreement valued up to $3,078,000, as shown in the table below. Services Fees Board Approval Original Agreement— Planning/Pilot Study $990,000 May 3, 2018 Amendment 1 — Phase 1 A Preliminary Design $550,000 May 2, 2019 Current Stantec Agreement $1,540,000 October 17, 2019 Regular Board Meeting Agenda Packet- Page 28 of 82 Page 5 of 16 Proposed Amendment— Phase 1A Final Design $1,538,000 Pending Total Contract Value with Amendments $3,078,000 The total estimated cost of Phase 1 A is approximately$35.5 million, of which approximately$27 million is construction costs, as detailed in Attachment 3. The total agreement value with amendments constitutes about 11.4 percent of the estimated construction cost, which appears high. However, this includes planning (which applies to all proposed project phases) and pilot testing costs. When compared to the design costs, the actual percentage ranges between 8-10 percent. This project is complex as it involves multiple facilities and includes the evaluation of many evolving options and the implication of future projects. COMMITTEE RECOMMENDATION The Engineering and Operations Committee reviewed this subject at the September 17, 2019 meeting and recommended approval. The Committee also requested that one additional alternative for the new storage tanks be evaluated. Information about this alternative was incorporated in the Position Paper. RECOMMENDED BOARD ACTION Authorize the General Manager to amend an existing professional engineering services agreement with Stantec Consulting Services, Inc. to increase the agreement ceiling from $1,540,000 to $3,078,000 for final design of the Filter Plant and Clearwell Improvements — Phase 1A, District Project 7361. Strategic Plan Tie-In GOAL ONE: Provide Exceptional Customer Service Strategy 1 - Build external customer relationships and awareness GOAL THREE: Be a Fiscally Sound and Effective Water Sector Utility Strategy 2- Manage costs GOAL FIVE:Maintain a Reliable Infrastructure Strategy 1 - Manage assets optimally throughout their lifecycle GOAL SIX: Embrace Technology, Innovation and Environmental Sustainability Strategy 1 -Augment the region's water supply, Strategy 3- Encourage the review and testing of technology to optimize and modernize business operations ATTACHMENTS: 1. Phase 1A Scope of Work 2. Business Case Evaluations 3. Total Phase 1 A Cost Estimate 4. Presentation October 17, 2019 Regular Board Meeting Agenda Packet- Page 29 of 82 Page 6 of 16 Attachment 1 Filter Plant and Clearwell Improvements - Phase 1A, District Project 7361 Scope of Work Staff recommends the following scope of work for Phase 1A final design: 1. Electrical Replacement and Upgrades: a. Electrical power distribution to the Electrical Substation 40 will be reconstructed to remove 2400v equipment and replace with new medium voltage distribution, step down transformers and 480v equipment. b. Clearwell Pumping Station Electrical. New 480v electrical switchgears including new motor control centers (MCC) and variable frequency drives (VFD) for the Utility Pumps, Backwash Pumps and Recycled Water Pumps for Zone 1. Equipment to be housed in a pre-engineered electrical building. 2. Recycled Water Storage Tanks Addition: a. Two new three-million-gallon (MG) recycled above grade water storage tanks will be constructed to replace the East Clearwell. The new tanks will be conventional steel tanks with a protective coating inside and out, which is standard practice for water storage structures. b. Appurtenances will be added to facilitate operation in series or parallel to provide chlorine contact time under different operating scenarios for high recycled water demand in the summer and low demand in the winter. c. The embankment for the East Clearwell will be partially removed to provide a site area for the new storage tanks. d. The West Clearwell will be maintained to facilitate recycled water delivery during construction and to provide backup storage. 3. Filter Rehabilitation: a. One filter of the existing four filters will be rehabilitated with new filter media and underdrains to confirm that the filter can reliably operate at a filtration capacity of 4.5 MGD/filter (million gallons per day/filter). b. All filters will receive reliability work to replace aging instrumentation and restore individual filter effluent turbidity measurement. c. Shade structures will be added to the filters to control attached algae growth and improve filter operation, which will reduce maintenance. d. The chemical feed reliability work will replace aging instrumentation, piping and valves on the hypochlorite system and update the feed pump motor control center. The coagulant system will be modified to feed a new filter aid. 4. Clearwell Pump Station (CWPS) Improvements: a. A new Utility Water pump will be added at the CWPS. b. The shade structure will be rebuilt to improve reliability of the Utility and Recycled Water delivery pumps. c. Replace the three Backwash Pump motors, as needed. October 17, 2019 Regular Board Meeting Agenda Packet- Page 30 of 82 Page 7 of 16 Attachment 2 Filter Plant and Clearwell Improvements - Phase 1A, District Project 7361 Business Case Evaluation (BCE) - Disinfection and Storage Alternatives Disinfection Alternatives: The viable BCE options that were examined for each disinfection alternative were: • DIS-1: Reinforced concrete partitions to create chlorine contact basins (CCBs) within the existing Clearwell (in each cell); • DIS-2: Reinforced concrete CCBs within the existing Forebays; • DIS-3: Stand-alone reinforced concrete CCBs (adjacent to the existing Clearwell); and • DIS-4: New In-Vessel UV (Ultraviolet) Disinfection Facility. The recommended alternative was DIS-3, stand-alone reinforced concrete CCBs that would be located south of the existing Clearwell adjacent to the filter effluent (FE) overflow junction structure. This alternative provides the most cost-effective long-term approach for disinfection. Other benefits include better maintenance access for cleaning and storage capacity. While alternative DIS-3 is the best approach, staff recommends postponing its implementation until Phase 1 B of the project and continue using the FE pipe as a contact time contactor supplemented by the recycled water storage to fulfill the Title 22 contact time requirements. Recycled Water Storage Alternatives: Since Phase 1A's main focus includes the provisions for safe, reliable storage of recycled water, another technical memorandum further analyzed various storage options. Staff prepared and developed BCEs on six alternatives: • RWS-1: Repair or replacement of existing Clearwell liner and cover; • RWS-2: Re-purpose the existing Forebays to be used as a Clearwell; • RWS-3: Provide two new storage tanks using above-ground steel; • RWS-4: Provide two new storage tanks using above-ground prestressed concrete; • RWS-5: Status Quo, a do-nothing alternative; and • RWS-6: Provide new storage using two concrete storage tanks with common wall construction. The recommendation is alternative RWS-3, to construct two new three-million-gallon above- ground steel storage tanks instead of replacing the liner and covers on the Clearwell. These tanks will be located inside the east cell of the Clearwell and connected to the final effluent overflow junction structure. Benefits of this alternative include better maintenance accessibility, the Clearwell structure will not be classified as an off-stream dam under the jurisdiction of the State Division of Safety of Dams, and it is the most cost-effective compared to the other alternatives. The tank location was based on the geotechnical site evaluation that revealed hard rock formation under the existing Clearwell structure, which is surrounded by Bay mud. October 17, 2019 Regular Board Meeting Agenda Packet- Page 31 of 82 Page 8 of 16 Attachment 3 Filter Plant and Clearwell Improvements - Phase 1A, District Project 7361 Estimated Capital Costs of Recommended Items Total Construction Total Project Cost Cost Project Component Electrical System Upgrades $7,500,000 $9,900,000 Clearwell Pump Station Renovation $1,700,000 $2,400,000 New Above Grade Steel Water Storage Tanks $15,200,000 $19,600,000 Filter Renovation (Filter No.1) $2,000,000 $2,700,000 Chemical Conditioning System Rehabilitation $600,000 $900,000 Total Capital Costs $27,000,000 $35,500,000 October 17, 2019 Regular Board Meeting Agenda Packet- Page 32 of 82 Item 5. (Updated Presentation) Attachment 4 r. FILTER PLANT AND CLEARWELL IMPROVEMENTS - PHASE 1A DISTRICT PROJECT (DP) 7361 �! Board Meeting October 17, 2019 Jean-Marc Petit, P.E. Director of Engineering and Technical Services DP 7361 : FILTER PLANT AND CLEARWELL IMPROVEMENTS PROJECT PROGRESSION TIMELINE Business Case East Cell Evaluations and Board Authorized Requesting Clearwell Cover 30%Design Agreement with Completed Board to Failure Stantec for Planning Authorize of Filter Plant and Amendment for Clearwell Project Final Design 2017 2018 DP 7361 2019 Phase 1A Board Authorized Stantec Board Recycled Water Submitted Authorized Clearwell Repairs Planning Amendment for Contingency Level Design Preliminary Project Report Design ` 2 1 Key Filter and Clearwell Clearrvell: MechProject Issues and Phasing: anical, Structural,and Failing Electrical Equipment;and East Cell Cleanvell Clearwell Pump Station Cover and Liners Pump Condition and Sizing Combined Storag t: and CIz Contact Filter Capacity an � Basins Effcacy Condition Electrical Power Distribution Voltage Supports Condition and Reliability t Filter Building Hydraulic Bottleneck Condition and Code _ into Forebays Upgrades .' • tom• � $'� ir �w Electrical Equipment;and ZL `* I• Phase Applied Water Pump Station 'F - (j Pump Condition and Sizing Phase 1B ' -- PROPOSED PHASE 1 A SCOPE FOR RECYCLED WATER (REW) PLANT FACILITI.- Upgrade/Replace Electrical Gear • New Clearwell Pump Station (CWPS)Electrical Facility • Replace Switchgear 43 to 480V Add 1 Utility Water Pump R • ReW Storage Two new Above Grade ; Steel Storage Tanks i rM • Rehab 1 Filter col _ f / • Upgrade Chemical Feed It - Upgrade/Replace Electrical Gear • New CW Electrical Facility • Modify Substation 40-2400V ' 4 CENTRAL SAN 2 WHY NOW? Meet Commitment for ReW Service Electrical Safety and Reliability (arc flash protection) We are a recycled water purveyor and provider (must maintain a level of service to plant utility water and Zone 1 customers) Reliability of producing recycled water (electrical, recycled water storage, chemical feed, and filter production) Phase 1A improvements are required now independently from the implementation of the Water Exchange Project and Concord Community Reuse Project MANY CUSTOMERS RELY ON A RELIABLE REW SUPPLY Reliance on ReW by Users Utility Water for the Treatment Plant Zone 1 Customers Maltby Pump Station = �- Auto Truck Fill Station '= Residential Fill Stations I CENTRAL SAN -w 4 3 ELECTRICAL POWER DISTRIBUTION CONCERNS • Transformers are on the road to failure based on oil analysis • Improve arc flash safety for critical gears to reduce safety risk to electricians - • Recent failures in 12kV feeder and Substation 40 -2400V bus bar highlight concerns • Medium voltage (2400V) power is obsolete, inefficient, and unnecessary for the motor sizes needed for current and future demands On January 16,2019,Substation 40 located at the Filter Plant experienced a failure which triggered a cascading series of events that led to a 16-minute, plant-wide power failure. �1 7 REW STORAGE/DELIVERY DEFICIENCIES East Clearwell cell is out of commission due to liner and cover failure • West Clearwell cell is now in service with a floating cover a--� t -� system in as a temporary solution Currently, no redundant storage is -� available to prevent ReW interruption East Clearwell cell cover triggered some tears and cover failures in ;, t December 2017. — On July 7,2019,the East Clearwell cell cover ripped, leading to its failure. This revealed excessive wear on both the cover and liner in the East Clearwell cell. 4 NEW WEST CLEARWELL CELL TEMPORARY COVER COMMISSIONED ON AUGUST 9, 2019 Sand bags are being used to hold the existing liner in place. BUSINESS CASE EVALUATION FOR REW STORAGE • RWS-1: Repairs or upgrades to the existing Clearwell • RWS-2: Repurpose the existing Forebays to be used as a --- WS-3:Provide new storage using two abov - und steel tanks • RWS-4: Provide new storage using two above- ground prestressed concre{e storage tanks • RWS-5:Status Quo, Do Nothing Alternative— Operate West Clearwell cell with temporary cover • RWS-6:Provide new storage using two concrete storage tanks with common wall - • RWS-7: Provide one new 6 MG cast in place concrete storage tank RWS=Recycled Water Storage ` ?4 5 FILTER DEFICIENCIES Proceed with rehabilitation of one of the four filter under Phase 1A • High solids loading produces short-filter runs requiring frequent backwashes and limits production capacity • Filter production capacity is limited �. • Filter media and underdrains need rehabilitation • Filter underdrain is outdated and subject to upsets of the gravel layer, which must be rebuilt to correct • Balance between filter production, net filtration, and energy cost • Filter effluent piping and control valves are undersized 11 TOTAL PROJECT COST - PHASE 1A Total Total Project Component Construction Cost Project Cost Electrical System Upgrades $7,500,000 $9,900,000 Clearwell Pump Station Renovation $1,700,000 $2,400,000 New Steel Storage Tanks $15,200,000 $19,600,000 Filter • $2,000,000 $2,700,000 Chemical Conditioning System Rehabilitation $600,000 $900,000 • $27,000,000 $35,500,000 12 6 PROJECT ALTERNATIVES/CONSIDERATIONS The Board could consider several alternatives for the Filter Plant and Clearwell Improvements Project— Phase 1A, as follows: Alternative 1: Further split Phase 1A project into three smaller projects and spread their construction over several fiscal years Alternative 2: Proceed with Sub-Project: Construct upgrades to Clearwell Pump Station and electrical distribution systems, including conversion from 2400V to 480V; postpone storage and filter rehabilitation Alternative 3: Status Quo - Do Nothing Alternative These alternatives are not recommended. 13 CENTRAL SAN RECOMMENDED BOARD ACTIONS Staff recommends the following: Authorize the General Manager to amend an existing professional services agreement with Stantec Consulting Services, Inc. to increase the agreement ceiling from $1,540,000 to $3,078,000 for final design of the Filter Plant and Clearwell Improvements - Phase 1A, District Project 7361 CENTRALSAN 7 QUESTIONS 15 s