Wastewater reuse in Tunisia: assessing a national policy

Abstract

An ambitious national wastewater reuse policy was launched at the beginning of the eighties in Tunisia. The area currently equipped for irrigation with reclaimed wastewater, mainly secondary effluents, is 6,500 hectares. It is planned to expand this area to more than 20,000 ha in the next years. The rate of reclaimed water reuse, 15% of the available water, is still low compared to the potential. Irrigation is practiced only six months per year; reclaimed water is not stored during the non irrigation season. Shifting from rainfed to wastewater irrigated crops is a progressive process. Irrigated schemes surveys point out that wastewater reuse development is hampered by crop restrictions more than by supply drawbacks. As a result, disinfecting secondary effluents in order to remove restrictions on water reuse is contemplated. Storing reclaimed water, in reservoirs or aquifers, would lead to more reliable supplies, water quality improvement and an increase in the rate of reuse. Developing the irrigation of golf courses, green belts and hotel gardens should be a convenient policy in tourist areas.