P9. Sewage treatment using gravel bed hydroponics (GBH) in Egypt and the United Kingdom

Field scale treatment plants have been constructed at Abu Attwa, Ismailia, Egypt and at Budds Farm, Havant, UK, so that comparisons may be made between the effectiveness of Gravel Bed Hydroponics

(GBH) in tropical and temperate climatic zones. These studies are entering their final phases and follow collaborative pilot studies (ref.l). Through extensive analysis, a design model is being produced for low cost effluent in both climatic zones.

Ismailia in Egypt has sewage disposal problems typical of the developing world. No effective treatment is available and there is severe contamination of the local lake which is used extensively for fishing and recreation. In the developing world, water supplies contaminated with sewage and other pollutants present a problem accentuated by the shortage of resources and technical expertise. A reliable low cost treatment system appropriate to the skills of the indigenous population is therefore needed. Gravel bed hydroponic (GBH) systems have the potential to satisfy this need and have the capacity, where appropriate, to replace high technology, high cost sewage treatment at a fraction of conventional construction and running costs. GBH may also be extended to produce agricultural crops as a sewage reuse system (ref.l).