Discussion and possible action on any and all matters regarding the selection and purchase of new headworks and grit removal systems for the West Wastewater Treatment Plant expansion project.  (Jorge Perez, Assistant Director of Public Works)

The City of San Luis is currently working with its consultant, Pacific Advanced Civil Engineers ("PACE") on the design of the West Wastewater Treatment Plant expansion. The expansion will double the treatment capacity of the plant and take it from 1.5 Million Gallons a Day ("MGD") to 3 MGD. The expansion also entails a treatment process change from a Sequential Batch Reactor ("SBR") to a Membrane Bioreactor ("MBR"). By doing this treatment process, the city will produce better quality water that can be reused for irrigation purposes, for example. At this time, the City has completed the request for qualification ("RFQ") process for the selection of Construction Manager at Risk (CMAR) for the wastewater plant expansion.  Currently, we are undergoing negotiations for the pre-construction services contract, which we will be presenting before the council at a later meeting.

The transition to MBR equipment entails additional changes to the plant and its equipment. Regardless of the treatment process, the headworks process is critical to all wastewater treatment plants. With that said, MBR plants require fine screens in their headworks section to maintain reliable and efficient membrane operation. There are various headworks (fine screen) vendors that could provide the equipment that the plant will require for the expansion. In an effort to make the best selection of the equipment for the City, PACE produced a performance-based specifications document and, in representation of the City of San Luis, conducted a request for proposal process. In response, we received three proposals for the headworks and grit removal equipment from the following manufacturers: Hydro-Dyne Engineering, Huber Technology, Inc., Kusters Water (Two alternatives provided), and Smith and Loveless. PACE thoroughly reviewed all three equipment proposals and produced a technical memorandum and recommendation to the City of San Luis.

In order to compare each manufacturer’s proposal, evaluation criteria were established and assigned a weight; the higher the weight, the more critical the aspect is to the project. Each equipment solution proposed was rated on a scale, with the highest score indicating the most competitive or best. For each criterion, the score and the weight were multiplied together. The sum of the multiplied numbers for each equipment/process system solution was used to arrive at the total score for each manufacturer’s proposed system.

Recommendation:
All of the manufacturer’s proposals for the MBR systems met the requirements of the performance-based specifications. The city has expressed the importance of lower capital and operating and maintenance ("O&M") costs, equipment performance, and ease of operation. Based on the Criteria Ranking developed as part of the performance-based specifications, Hydro-Dyne Engineering, Inc. scored the highest and is the recommended manufacturer to supply the complete headworks and grit removal process equipment for the City of San Luis West Wastewater Treatment Plant Phase 1 MBR Upgrades.