View File - Development Services - City of Oxnard

WATER RESOURCES TECHNICAL REPORT• Property availability for expansion and construction of Phase 2 facilities• Groundwater basin water levels in response to future climatic conditions (e.g., extendedwet or dry periods)• Evolving regulations, specifically with respect to Department of Health and Safetyregulations which may affect well location, spacing, and operation• Location of future private water supply wells• Feasibility of recycled water injection (e.g., clogging and/or geotechnical issues)• Mixing properties of recycled water and groundwater when recycled water is injectedinto aquiferDetailed design for a large portion of Phase 2 components is dependent upon the results ofimplementing Phase 1. Therefore, Phase 2 facilities are described in less specific detail thanPhase 1.4.4.1 Tertiary Treatment Facility ExpansionThe TTF would be expanded from 5 mgd to a capacity of up to 32.6 mgd. This wouldrequire the addition of two additional secondary effluent pumps, three strainers, eightmicrofiltration (MF) or ultrafiltration (UF) units, and a second 600,000-gallon tertiaryeffluent storage tank.4.4.2 Advanced Water Treatment Facility ExpansionThe AWTF would be expanded from 3.8 mgd to a capacity of up to 15.3 mgd for treatmentof and blending with tertiary treated water for agricultural irrigation, distribution ofpermeate to industrial users, and delivery of recycled water to ASR wells. If BlendingOption 1 is implemented in Phase 1, potable water from the Oxnard-Hueneme Pipeline maybe added after advanced treatment for the purposes of blending. With the addition ofpotable water for blending, a total of up to 24 mgd could be available for distribution.Expansion of the treatment capacity of the AWTF will require a larger capacity recycledwater booster pump station (24 mgd) to pump treated water to irrigation users and/or theASR well locations. The pump station would be contained within the pump station buildingconstructed under Phase 1. In addition, a second 300,000-gallon storage tank would beconstructed to store the additional permeate produced by expansion of the treatmentfacility. This would increase onsite permeate storage capacity from approximately300,000 gallons to approximately 600,000 gallons.4.4.3 Recycled Water Delivery System ExpansionRecycled Water Conveyance for Agricultural IrrigationThe recycled water delivery system would be expanded from 3.4 mgd to a capacity of24 mgd. Irrigation quality recycled water would continue to be generally distributed to thePleasant Valley area approximately 9 months each year; however, it is anticipated thatdelivery of recycled water would be expanded to connect to additional existing irrigationdelivery systems. Under Phase 2, the Recycled Water Delivery System would connect to theW112003002SCO LW1458.DOC/ 033390002 61