An Economic Analysis of Salinity Problems in the Mahaweli River System H Irrigation Scheme in Sri Lanka

Salinity problems are primarily associated with coastal areas and irrigated lands in the dry zone of Sri Lanka, where the total irrigated area is about 0.5 million hectares. Since irrigation has been practiced in these areas from ancient times, salinity might have been a problem at least in patches of irrigated lands. With the development of modern irrigation networks, it is anticipated that salinity would become a problem over the years as in many other countries. Only a few systematic studies exist on the soil salinization problem in Sri Lanka, and there are no records of the actual extent of lands affected by salinity, or data that indicate its trend. Most of the available information comes from sporadic surveys. Recently, however, concerns were expressed that most of the large-scale projects would face salinity problems. Due to the inadequacy of related studies, the actual extent of the problem, both in economic and environmental terms, is unknown in Sri Lanka. This study focused primarily on the problem of soil salinity in the Mahaweli irrigation scheme. The Mahaweli project is one of the largest irrigation projects in South East Asia. This study attempted to measure the impact of soil salinization on rice production and on the environment. It also assessed the optimal control of salinity at the farm and project level for better water management and environmental protection.