Orange County's Groundwater Replenishment System: Water Quality Monitoring and Facility Expansion in the Face of Changing Regulations

The Groundwater Replenishment System (GWRS) is a 70 MGD indirect potable reuse project located in Fountain Valley, California. Two ongoing state regulatory processes have the potential to influence operations and water quality monitoring for GWRS and other groundwater recharge reuse projects (GRRPs) in California. The first is the effort by the State Water Resources Control Board (SWRCB), in collaboration with the California Department of Public Health (CDPH), to establish monitoring requirements for constituents of emerging concern (CECs), such as pharmaceuticals and personal care products (PPCPs) and endocrine disrupting compounds (EDCs), for GRRPs. The second process is the legislative mandate for formal adoption of the CDPH Draft Groundwater Recharge Reuse Regulations (Draft Regulations) by December 2013. OCWD's current treatment processes and monitoring programs should address most, if not all, of the immediately forthcoming CEC testing requirements. However, potential changes to requirements for subsurface retention time, blending, and unit process monitoring would impact future GWRS operations and uses.