Reusing Treated Wastewater for Irrigation of Raw-Eaten Vegetable Crops in Monterey County, California

The demonstration project was entitled the Monterey Wastewater Reclamation Study for Agriculture (MWRSA). It was principally a field trial study of the feasibility of irrigating food crops which may be consumed raw with reclaimed municipal wastewater effluent. The MWRSA field operations site was located on a farm in Castroville, California. The three water types being compared were filtered secondary effluent (Filtered Effluent); coagulated, flocculated, settled, and filtered secondary effluent (Title-22 water); and local well water as a control. The purpose of the experimental plots was to generate reliable statistical data on the separate effects of the water types and fertilizer rates on the various crops and the soil. Soils, plant tissues, and irrigation waters in the experimental plots were frequently sampled and extensively analyzed for chemical, physical, and microbiological characteristics, including viral contamination.