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The irrigated arid and semi-arid zones in India face twin problems of overall water scarcity and waterlogging accompanied by salinity. Subsurface drainage has proved successful in the rehabilitation and conservation of waterlogged saline soils. Drainage water from subsurface drainage systems seems to be an important source of water in the next millennium to tide us over the anticipated water scarcity problem in agriculture. However, the drainage waters from subsurface drainage systems are often saline and in the absence of a natural outlet, their disposal creates a problem. Various possible options have been discussed to mitigate the environmental threat posed by low quality drainage waters. Issues relating to potential reuse of low quality drainage waters along with management practices are addressed. Effects of factors influencing the long-term sustainable use of saline drainage waters are presented and it is emphasized that special management practices have to be followed/evolved for site-specific water quality, soil, crop and climatic conditions. However, the extent of salt leaching and crop establishment will depend on the total amount of monsoon rains and adequate subsurface drainage. It has been concluded that the use of a part of the saline drainage water in the post-reclamation phase will not only augment the water supply but also minimize effluent disposal requirements. Copyright (C) 2004 John Wiley Sons, Ltd.