A system dynamics simulation model for the assessment of water resources in Sri Lanka

Ability to accurately predict water availability in a country is vital in planning its water resources development activities. Traditional approach used is based on a water balance and a demand projection. The projections are variant of current trends and subject to considerable uncertainty. Besides, they do not capture dynamic character of climatic, socio-economic and environmental change etc., and their impact on water use. Thus, the traditional approach is subject to a wide margin of error. In contrast, a novel approach, “system dynamics” offers a new way of modeling future dynamics of complex water systems increasing the ability to correctly assess and predict availability and use of water. This paper presents a system dynamics based simulation model to predict water resources in Sri Lanka. Using the model water availability was predicted and Sri Lanka will have sufficient water in the year 2025. However, in several districts water availability will decrease rapidly while others will not get much affected.