One Design for Two Subregional Membrane Bioreactor Water Reclamation Facilities

The Victor Valley Wastewater Authority (VVWRA) provides wastewater treatment and water recycling for the Victor Valley region, which includes the Cities of Victorville, Hesperia, and the Town of Apple Valley. VVWRA decided to design and construct scalping plants within the overall wastewater collection system in order to reuse water closer to the end users and to relieve the main interceptors. The first two scalping plants to be developed under this overall reuse goal are the Hesperia and Apple Valley Subregional Water Reclamation Plants (WRPs). The WRPs will serve as scalping plants in order to deliver a fairly consistent recycled water production of 1.0 million gallons per day (mgd) with phasing plans to 2.0 mgd and ultimately to 4 mgd.Varying influent flow and loading characteristics along with stringent future discharge limits posed several challenges during design. The main challenge and purpose for the design was to develop one common design that would satisfy the varying influent conditions at the two WRP locations and provide future flexibility without overdesigning one facility due to the other facilities' influent characteristics. Since these WRPs will also be constructed in wastewater collection areas that will undergo future growth, the zoning characteristics needed to be taken into account in the planning of the WRPs. The ability to base load these scalping plants during start-up with minimum collection system flows below the base flow was also addressed. The outcome was a flexible design that provided options for handling a range of influent conditions and future regulations, while allowing for some site customization to keep down the construction costs.The challenges faced by the design team to develop one design for the two WRPs that will be located within different wastewater collection basins are discussed in this paper.