ABSTRACT
Constructed wetlands can provide a low-cost wastewater treatment alternative to achieve secondary treatment for small to medium-size communities. This chapter presents a case study of a constructed wetlands system at Gustine, California utilizing emergent aquatic vegetation. History, pilot-study effort, construction problems, construction cost, and initial performance data are included. The wastewater treatment system for Gustine consists of 11 oxidation ponds operated in series followed by a constructed wetlands system and chlorination/dechlorination facilities. The oxidation ponds have a net area of 17 ha and provide pretreatment of Gustine’s strong waste prior to wetland application. Operators can draw pond effluent from any one of ponds 5 to 11, adjusting detention time in the ponds (24–54 days), regulating waste loading on the wetland, and avoiding application of heavy algae concentrations during summer. The wetlands system and other treatment plant improvements were constructed in 1986 and 1987.
