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HomeMy WebLinkAbout03.c. Review draft Position Paper authorizing the General Manager to execute a construction change order with W.M. Lyles Co. to replace a 900-horsepower Variable Frequency Drive at the Treatment Plant Headworks Facility, District Project 7327 Page 1 of 2 Item 3.c. CENTRAL SAN BOARD OF DIRECTORS ' POSITION PAPER DRAFT MEETING DATE: APRIL 25, 2018 SUBJECT: REVIEW DRAFT POSITION PAPER AUTHORIZING THE GENERAL MANAGER TO EXECUTE A CONSTRUCTION CHANGE ORDER WITH W.M. LYLES CO. TO REPLACE A 900-HORSEPOWER VARIABLE FREQUENCY DRIVE AT THE TREATMENT PLANT HEADWORKS FACILITY, DISTRICT PROJECT 7327 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 ISSUE Board of Directors (Board) approval is required to execute a construction contract change order in an amount exceeding $100,000. BACKGROUND The Influent Pump Station is part of the Headworks Facility and is equipped with five influent pumps that convey all of the incoming wastewater to the Primary Sedimentation Tanks or the Wet Weather Bypass Structure. I nfluent Pump Nos. 1 and 2 are connected to Wet Well No. 1 and I nfluent Pumps Nos. 3 and 4 are connected to Wet Well No. 2. Pump Nos. 1 through 4 pump to the Primary Sedimentation Tanks and Pump No. 5 can only pump directly to the bypass structure, and is intended to be used only during wet weather events. Recently, the Variable Frequency Drive (VF D)that controls Influent Pump No. 1 has failed. The service provider and maintenance staff attempted multiple repairs on this VFD; however, these repairs have not proven to be reliable. At the Board Meeting on March 8, 2018, the General Manager made an announcement regarding this issue and notified the Board that the Capital Projects Division is pursuing a Change Order to replace this VF D. April 25, 2018 EOPS Regular Committee Meeting Agenda Packet- Page 44 of 72 Page 2 of 2 The Headworks Screening Upgrade Project, District Project 7327 (Project)will be replacing Bar Screens Nos. 3 and 4 with new multi-rake screens this summer. Wet Well No. 2, which is downstream of Bar Screen Nos. 3 and 4, will be out of service for extended periods during this time and Influent Pumps Nos. 3 and 4 will not be available for operation. Without Influent Pump No. 1, the Headworks Facility may not be able to reliably process daily peak flows during the Project. Because of the urgency of replacing the VFD and the criticality of maintaining a working I nfluent Pump Station, the Capital Projects Division issued a Request for Proposal to W.M. Lyles Co. under the Project to retrofit the VFD with replacement components to restore the VFD to reliable service. ALTERNATIVES/CONSIDERATIONS The Influent Pump Electrical Improvements, District Project 7328, includes replacement of all the Headworks VFDs. This project is in the planning stage and is scheduled for construction in Fiscal Year 2019. Staff will continue this project, re-evaluate the current schedule, and report back to the Board during consultant selection authorization. Staff authorized the purchase of the equipment since it was within delegated authority; however, the overall cost needs to be authorized by the Board. The new VFD is scheduled to arrive later this month with installation by the end of May 2018. FINANCIAL IMPACTS The VFD replacement cost is estimated at$120,000. This includes the VFD purchase, installation, and contingency. These costs shall be paid for under the Influent Pump Electrical Improvements, District Project 7328. COMMITTEE RECOMMENDATION The Engineering and Operations Committee reviewed this matter at the April 25, 2018 meeting and recommended approval of the Change Order with W.M. Lyles Co. RECOMMENDED BOARD ACTION Authorize the General Manager to execute a Change Order up to $120,000 with W.M. Lyles Co. to replace the Headworks VFD No. 1 under the Headworks Screening Upgrade, District Project 7327. April 25, 2018 EOPS Regular Committee Meeting Agenda Packet- Page 45 of 72