Infiltration Percolation for Reclaiming Stabilization Pond Effluents

Abstract

Reusing reclaimed municipal wastewater contributes to the water management strategy of Mediterranean seaside resorts. By supplying irrigation water, it allows the lay out of lanscaped areas and of golf courses. By reducing or eliminating the discharge of treatment plant effluents to water courses and to the sea, it reduces the contamination of bathing water and coastal ecosystems. The development of this policy depends on the availability of cost effective processes able to decontaminate the effluents of the existing wastewater treatment plants. The Grau du Roi resort population is more than 100,000 during summer. Wastewater is treated in a 20 ha stabilization pond; the municipality has planned to reuse 5,000 m3/d of pond effluents for turfgrass and landscape irrigation. Pond effluents will be reclaimed after a passage through an infiltration percolation facility. Tests were performed on laboratory columns and on a pilot plant in order to evaluate the performances of this process. Spreading 0.75 m pond effluents per day on a 1.5 m deep dune sand bed, on a 5 days - 2 days cyclic application - drying schedule, will provide the microbiological quality required for landscape irrigation. A design and a management method of the treatment plant were elaborated in order to ensure the performances of the process.