Africa is hit hard by desertification and each year more fertile land is claimed by the desert. The only way to counter this problem is to plant more forests. However, lack of clean water for the proper growth and nourishment of trees is another issue in the region.
The Egyptian government launched an innovative project back in the 1990s to control desertification by planting forests using the wastewater. The project turned out to be very successful and is currently producing four times the eucalyptus wood than the pine plantation in Germany.
The Serapium forest is almost two hours away from Cairo, the Egyptian capital. The plantation is spread over an area of 200 hectares and is home to both native and non-native plants and trees, including the commercially valuable varieties like mahogany.
Egypt receives twice the sunshine as Germany, at the rate of 2200kWh per meter squared. The living soil has no chances of surviving and producing anything good in these circumstances. However, the Egyptian researchers discovered that watering the plants with the sewage water helped the trees grow. The wastewater is so packed with nutrients that there is no need of adding any other fertiliser to spur the growth.
The sewage water used is first mechanically filtered to remove garbage and dirt from the water. Next, oxygen and microbes are introduced to encourage decomposition of the organic matter. The treated sewage water is rich in nitrogen and phosphates, just like the commercially available fertilisers. The water is fit only for use in the regions where nothing is grown for human consumption.
After 15 years, the Serapium forest has produced 350 cubic meter wood per hectare. The researchers estimate that if its 80 percent of the sewage effluent was used by the country, Egypt could transform a whopping 650,000 hectares of desert into forests.