Surface and subsurface drainage of metropolitan city in arid zone

Qualitative and quantitative aspects of both the surface and subsurface drainage in the city of Riyadh, in the Kingdom of Saudi Arabia, are studied with a view to (1) Determining the resuse potential; and (2) estimating the magnitude of the problem of the rising water table. Five gaging and sampling stations are established at the outfalls of the city's drainage network, and the quality and quantity of both storm runoff as well as dry-weather flow are monitored over a period of six years. The quality and quantity of this drainage is such that it is well within reuse schemes, most notably for irrigation purposes. Treatment schemes for reuse of this drainage water for irrigation and industrial purposes are proposed. The primary cause of the water-table rise is also identified.