Project Type

Comprehensive Services for Indirect Potable Reuse Implementation


Monterey One Water


Marina, CA

Current Status

Ongoing since 2012

Key Features

  • Advanced treatment process design (through 100% design) and procurement
  • Engineering services during construction
  • Title 22 Engineering Report and WDR/WRR permitting
  • Operation Optimization Plan
  • Startup and commissioning
  • Ocean discharge compliance and NPDES permitting

Project Overview

To augment the region’s potable water supply, Monterey One Water (M1W) contracted with Trussell to develop a 5-mgd Advanced Water Purification Facility (AWPF) as part of their Pure Water Monterey Project. The project involves treating challenging secondary effluent from M1W’s Regional Treatment Plant (RTP) through ozonation, membrane filtration, reverse osmosis, and UV-advanced oxidation process (UV-AOP) and then injecting the highly purified water into the Seaside Basin aquifer. Trussell has been involved with the project since treatability testing began in 2012 and continues to support M1W through ongoing operations optimization.

Trussell worked closely with the project team to design the chemical storage facilities and ozone, UV/AOP, and post-treatment stabilization processes, as well as control logic for these systems for smooth operation of the AWPF. Additionally, Trussell (1) supported development of design criteria and process and instrumentation drawings for the ozone, UV/AOP, and post-treatment systems, (2) produced process equipment pre-selection documents, including technical specifications, for the ozone and UV/AOP systems, (3) evaluated process equipment pre-selection proposals for the ozone and UV/AOP systems, and (4) developed the process mechanical drawings for the ozone, UV/AOP, post-treatment, and chemical building areas. During construction, Trussell reviewed shop drawings and supported development of the O&M Manual.

Trussell has assisted M1W with permitting efforts including California Environmental Quality Act (CEQA) support, development of at Title 22 Engineering Report for the State Water Resources Control Board Division of Drinking Water (DDW), obtaining the Waste Discharge Requirements and Water Recycling Requirements (WDR/WRR) permit, assessment of Ocean Plan compliance for M1W’s National Pollutant Discharge Elimination System (NPDES) permit, development of the Operation Optimization Plan (OOP) for DDW, and review of the AOP Test Plan for DDW. The Engineering Report, WDR/WRR permit, revisions to the NDPES permit using an innovative multiple dilution credit approach, OOP, and AOP Test Plan have all been approved by DDW and the Regional Water Quality Control Board (RWQCB). Trussell has also assisted with geochemical leaching analysis to assess injected groundwater quality.

Want to learn more about this project?

Download the PDF Project Brief by clicking the button