Sewage salvation
Too little fresh water, too much effluent. Mahmoud Bakr looks at an innovative way of dealing with the dilemma
Egypt is a water-scarce country which generates around 5.5 billion cubic metres annually of sewage, which, in turn, corresponds to 10 per cent of Egypt's share of the Nile waters. It is estimated that Egypt produces 2.4 billion cubic metres of unutilised treated water annually, including 1.2 billion cubic metres in the Greater Cairo area, 0.3 billion cubic metres in Alexandria, and a total of 0.9 billion cubic metres in the other governorates.
In the past, both treated and untreated sewage water was simply pumped into the sea or rivers, disposed of in the desert or allowed to seep into the ground. This wasteful method of disposal has resulted in the pollution of beaches, desert areas and valuable underground water sources.
In order to deal with this state of affairs, the Ministry of Environmental Affairs recently adopted an innovative programme through which treated sewage water would be used for forestry projects. According to Mamdouh Riyad, minister of state for environmental affairs, "both the preservation of the environment and our recognition of the need to use treated sewage water are strategic requirements. We need to utilise waste water in a manner that increases our national income, as well as limiting its damaging effect on the environment."
Today, treated effluent generated in cities is used in the cultivation of forests in desert areas bordering sewage treatment plants. "The results are encouraging," said the minister, "the forests help reduce the severity of sand storms, as well as being economically viable."
The government is planning to cultivate forests on 400,000 feddans (acres) of desert land using treated sewage water. The first phase of the project, which has already begun, has been initiated on an area of 82,940 feddans and will take about 10 years to implement. The forests are expected to produce lumber worth LE4.9 billion, with each feddan expected to produce profits of up to LE11,000 per annum.
The forested areas will draw water from about 72 sewage treatment plants. Areas suitable for forestation have been found for 25 stations and viable land is currently being ear-marked for 47 other stations. The effects of forestation on ground water is also being studied at 69 of the selected 72 sites.
It is estimated that each feddan of forest will use up to 9,125 cubic metres of water per year if watered by the traditional irrigation method, and 6,000 cubic metres if the drip method is employed.
The Serabium forest in Ismailia is one of 15 forests currently under cultivation. According to engineer Mohamed El-Baqli, director-general of forestation at the Ministry of Agriculture and manager of Serabium, the forest now covers 400 feddans and will be expanded gradually to encompass 1,000 feddans.
Work in the forest began in January 1998. The land was levelled with bulldozers, a process which took 5 months to complete. The forest is watered via the drip method and uses an estimated 90,000 cubic metres per day of treated waste water.
According to Al-Baqli, "the forest is expected to yield a return after a period of 15 to 20 years, in keeping with the growth cycle of the trees involved. This is why fast-return ventures have also been incorporated into the project to stimulate investment. These include silkworm production and the cultivation of the sissal plant, which is used to manufacture medical preparations such as cortisone and a vegetable wax suitable for industrial use. The fibres of the sissal plant are also used to manufacture rope, bags, paintbrushes and filling for cushions."
Currently under consideration is the possibility of cultivating decorative plants.
