Possibilities And Requirements For A Water Quality Monitoring System In The Ayeyarwady Basin

Abstract

Myanmar lacks a water quality monitoring system to monitor changes in water quality in the Ayeyarwady Basin. This study aims to find to what extent changes in water quality can be measured in the Ayeyarwady basin and to identify requirements for a water quality monitoring system. In this study, the current water quality monitoring systems of the Ayeyarwady, Mekong, Chao Phraya and Hong (Red) River Basins were compared. Several contamination sources were used to identify contamination scenarios. A river model of the Ayeyarwady and its main tributary, the Chindwin, was made to understand the workings of the river system and the distribution of contaminants throughout the Basin after contamination events. This study found that contamination is diluted to a high degree over long distances in the Ayeyarwady Basin. At low river discharge, the remaining contamination peak downstream of large contamination events like waste water treatment plant failure or tailings dam failures occurring upstream in the river near the limits of detection. During high river discharge these concentrations can be over 17 times smaller. The study showed that in case of pulse water quality incidents for most common water quality parameters, the monitoring system should have a temporal frequency of once per week with an analytical accuracy of around 0.1 microgram/l. A high-quality monitoring station is required in both river branches just upstream of the confluence of the Ayeyarwady and Chindwin rivers as significant dilution occurs here. Finally, it is crucial to clearly define and distribute measurement responsibility.