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HomeMy WebLinkAbout04.c. Receive update on the Dublin San Ramon Services District (DSRSD) - East Bay Municipal Utility District (EBMUD) Recycled Water Authority (DERWA) Temporary Wastewater Diversion Project Page 1 of 5 Item 4.c. ,orVIOIN SAN June 10, 2019 TO: REAL ESTATE, ENVIRONMENTAL AND PLANNING COMMITTEE FROM: DAN FROST, SENIOR ENGINEER REVIEWED BY: DANEA GEMMELL, PLANNING AND DEVELOPMENT SERVICES DIVISION MANAGER JEAN-MARC PETIT, DIRECTOR OF ENGINEERING AND TECHNICAL SERVICES ROGER S. BAILEY GENERAL MANAGER SUBJECT: RECEIVE UPDATE ON THE DUBLIN SAN RAMON SERVICES DISTRICT (DSRSD) - EAST BAYMUNICIPAL UTILITY DISTRICT (EBMUD) RECYCLED WATER AUTHORITY(DERWA) TEMPORARY WASTEWATER DIVERSI ON PROJECT Please see the attached presentation. Strategic Plan Tie-In GOAL ONE: Provide Exceptional Customer Service Strategy 3- Maintain a strong reputation in the community GOAL SIX. Embrace Technology, Innovation and Environmental Sustainability Strategy 1 -Augment the region's water supply ATTACHMENTS: 1. Presentation June 10, 2019 REEP Committee Meeting Agenda Packet- Page 24 of 30 Page 2 of 5 T r' 1 DERWA DIVERSION PROJECT UPDATE Dan Frost, P.E. Senior Engineer Jean-Marc Petit Director of Engineering & Technical Services REEP Committee Meeting June 10, 2019 h RECAP OF DERWA'S REQUEST • In January 2017, Central San received a written request from DERWA to develop a memorandum of understanding to explore a pilot project to divert a portion of the raw wastewater from the San Ramon Pumping Station from May through September every year. • The wastewater would be diverted through DSRSD's existing collection system to DSRSD's treatment plant, for the purpose of producing and distributing recycled water to meet DERWA's peak summer irrigation demand. • DERWA made this request due to the need for a temporary supplemental supply to help meet recycled water demands in the EBMUD and DSRSD service areas until wastewater flows increase with development and other long-term supply options are identified. CENTRAL SAN � z 1 June 10, 2019 REEP Committee Meeting Agenda Packet- Page 25 of 30 Page 3 of 5 TEMPORARY WASTEWATER DIVERSION • Short-term diversion that is only used to shave DERWA's current peak summer recycled water demand • In 2017, the diversion would have been needed for approximately two weeks • In 2018, the diversion would not have been needed • Would divert —1 .3 million gallons per day (MGD) of the —3.5 MGD average dry weather wastewater flow from the San Ramon Pumping Station 3 CENTRALSAN BOARD ADOPTED NINE GUIDING PRINCIPLES FOR AN AGREEMENT ON AUGUST 16, 2018 1. No Adverse Financial Impact to Central San 2. No Adverse Financial Impact to Concord and Clayton 3. Consistency with Existing Bond Covenants 4. Consistency with Proposition 218 5. Community Acceptance 6. Temporary Nature 7. Mitigation of Technical and Operational Impacts 8. Benefits to Central San Customers 9. Facilitate a Sustainable Solution to the Region's Water Supply Shortage CENTRALSAN 2 June 10, 2019 REEP Committee Meeting Agenda Packet- Page 26 of 30 Page 4 of 5 BOARD AUTHORIZED GENERAL MANAGER TO EXECUTE DERWA TEMPORARY DIVERSION AGREEMENT JANUARY 17, 2019 • Initial term is three years with two one-year extensions possible (by mutual written agreement), not to exceed five years • The Nine Guiding Principles are included in the agreement: • If Central San"reasonably determines"that operation of the project is no longer consistent with the Guiding Principles, Central San may terminate the Agreement • DERWA is responsible for the cost to design and construct the project • If Central San terminates Agreement within the initial term, the Parties will meet in good faith to determine appropriate Central San reimbursement to DERWA, if any • Requires annual reporting by DERWA on: • The project's adherence to the Guiding Principles • DERWA's efforts to develop alternative supplies s CENTRALSAN LATEST WASTEWATER DIVERSION CONCEPT 22 M22 M -] 'M 16 J � 36V V.lit M5 22 min l 4 '•f5ll� 6 3 R16 6 M16 �. M2R ;:ll • Replace existing Central San Manhole 11 with a new diversion structure with weir gates to control the direction of wastewater flow • Replace existing emergency overflow pipe between Manhole 11 and DSRSD Manhole 20 with new pipe at a lower elevation more ideal for diversion CENTRALSAN 3 June 10, 2019 REEP Committee Meeting Agenda Packet- Page 27 of 30 Page 5 of 5 PROJECT SCHEDULE OVERVIEW • February 2019—Agreement Executed with DERWA • February to March 2019—Staff Reviewed and Provided Comments on 1St Design Submittal (based on original diversion concept)from DSRSD • April 2019—The new diversion concept was developed • May 2019— Received 2nd Design Submittal (based on new diversion concept)from DSRSD • June 2019 —Staff Providing Comments on 2nd Design Submittal • DSRSD Next Steps: • Update Design Submittal to Address Comments • Considering Pre-Purchasing Gates to Expedite Construction • Evaluating Expedited Contractor&Equipment Procurement Options • Construction may start as early as mid to late Summer 2019 7 CENTRAL SAN QUESTIONS? 8 4 June 10, 2019 REEP Committee Meeting Agenda Packet- Page 28 of 30