For hydroelectric reservoirs, the rainfall on the main dam and the water level of the upstream and downstream of the main dam need to be monitored. Photo: Minh Ngo
Specifically, the 7 types of works that need to have hydro-meteorological monitoring are: 1- airports; 2- irrigation reservoirs with flood control gate and hydroelectric reservoirs with total capacity from 3 million m3, reservoirs regulated by the inter-reservoir operational process on river basins; 3- type I and type II ports; 4- bridges across estuaries, straits, gulfs or internal water areas with aperture from 500 m; 5- broadcast towers combined with tourism and business services on the towers; 6- cable cars for sightseeing and tourism activities; 7- National Parks.
As stipulated by the Decree, the owners of works shall based on the above-mentioned regulations decide on the content of hydro-meteorological monitoring as per the requirements of exploitation and deployment, but shall ensure the minimum requirements for each type of works. For hydropower reservoirs, the following monitoring work will be done: the rainfall at the main dam, water level at upstream and downstream of the main dam, calculating discharge to the reservoir, discharge flow, turbine discharge flow, and estimated increase of water level based on the flow to the reservoir. The frequency of monitoring shall be 4 times a day by Hanoi time at 1.00, 6.00, 13.00 and 19.00 during the flood season and 2 times a day at 1.00 and 19.00 during the dry season. In case of flood control operation, monitoring and calculation frequency shall be every one hour as minimum.
Details of the Decree are as per the file attached.