Linkages of transboundary water allocation and its eco-thresholds with international laws

Based on the case study of Lancang-Mekong river, analyses have been made on the database of bilateral and multilateral treaties/agreement of transboundary water resources in the world and the regional agreements of Mekong River, the principles of the equitable and reasonable utilization, and causing no significant harm, index system and related models on transboundary water allocation have been worked out, and the key ecologic thresholds of the maximum and minimum water flow and water level of water allocation have been defined. By using the data of water resources development and utilization at present and development objectives of the riparian states, to ensure the ecological environment demand of water in the river basin and based on the water yields in the riparian states, 5 types of 3 kinds of water allocation schemes with water volume as the core have been set up, viz., the whole allocation, the project allocation and the river-basin-integrated allocation. By comparing the scheme, the results show tion scheme can equitably beneficial effect of each that （1） the whole allocadefine the available water consumption volume of each state, but cannot sustain the ecological objectives in the river basin; （2） the project allocation scheme can meet the needs of the most riparian states, but cannot meet the drainage ecologic need （esp. to prevent the intrusion of saltwater in Mekong Delta） and the development objectives of Vietnam; （3） the integrated allocation scheme can meet the development need of each state in the predictable period and sustainability of drainage ecology, but the beneficial countries should make compensation to the others so as to materialize the fairness of transboundary water allocation.

Linkages of transboundary water allocation and its eco-thresholds with international laws