Trans-Boundary River Basin Management in Central Vietnam
Agriculture field in Hoa Khuong commune, Da Nang. Photo: Thanh Ngo, ISET-International
Early November 2017, storm no. 12 (Typhoon Damrey) with level 12 winds, level 15 gusts and heavy rain made a landfall on the central coast of Vietnam. Fearing that the increasing water levels would risk reservoir safety, many hydropower reservoirs opened their floodgates and released huge amounts of water for several days continuously, causing extensive flooding downstream.
At the time, Da Nang City was at the height of preparation to host the Asian and the Pacific Economic Corporation (APEC) Summit from November 6-11, 2017, and Hoi An City of Quang Nam Province was also selected as the venue for the visit of the spouses of APEC leaders, Ministers and other representative agencies on November 7, 2017. Though escaping the brunt of the devastating typhoon, both municipalities still suffered tremendous damages . Floodwater released from the reservoirs of Song Tranh 2, Dak Mi 4, Song Bung 4 hydropower plants  caused the Thu Bon and Vu Gia rivers to swell, raising floods in many low-lying areas of Da Nang and Quang Nam, with Hoa Vang district of Da Nang city and Dai Loc and Dien Ban districts of Quang Nam province being the hardest hit. As reported by local people in Hoa Khuong commune, Hoa Vang district, the flood caused by Typhoon Damrey in 2017 was an extreme event, with some flood posts in the commune recording flood levels higher than those in the historical flood in 1999, partly due to changes in the local landscape as a result of construction and renovation of belt roads and national highways in the area (such as DT406, DT08, and National Highway 14B).
Occurring right before the APEC week, the severe impacts of storms and flooding on all aspects of the socio-economic life in Quang Nam and Da Nang was put in the spotlight. However, not only in 2017 with typhoon Damrey but year after year, flooding and also droughts are becoming more and more severe, affecting the lives, livelihoods, safety and health of local people. Moreover, during the recent years, flooding and droughts in this region have become less and less mere ‘natural’ events, but more and more driven by the impacts of human activities, particularly the construction and management of the cascade of hydropower dams, water resource management infrastructure, and other infrastructure in the Vu Gia – Thu Bon river basin. An inter-provincial river system, originating from the mountainous areas of Quang Nam and reaching the sea via estuaries in both Quang Nam and Da Nang, the Vu Gia - Thu Bon poses a tricky multi-variable problem for both municipalities in how to manage its water balance in the context of the existing infrastructure system from upstream to downstream areas, especially when rains and storms are becoming more unpredictable because of climate change.
The policy brief document featured here describes the experience of a project led by ISET and funded by the Global Resilience Partnership in support of an official platform of Quang Nam and Da Nang aimed at promoting inter-provincial dialogues, investigations and collaboration to address flooding, water shortages, among other water related issues in shared Vu Gia – Thu Bon river basin. The document provides important insights and lessons for (inter-)provincial and national policies for river basin management in Vietnam, especially in the context of expected national policy on the establishment and operation of new River Basin Organizations in the country.
 By November 16, 2017, a total of 36 people had been killed and 1 person was missing in Quang Nam because of Typhoon Damrey. Source: https://news.zing.vn/quang-nam-thiet-hai-1500-ty-do-mua-lu-va-sat-lo-post796570.html
 According to the Steering Committee for Disaster Prevention and Control, Search and Rescue of Quang Nam province, floodwater release from the reservoirs was at the highest rate at 21:00 of November 4, 2017. Specifically, Song Bung 4 reservoir water was released into the Vu Gia river at 4,270 m3/s (the rate was only 1,658 m3/s at 12:00 of the same day), Song Tranh 2 reservoir water was released into the Thu Bon river at 2,198 m3/s (the rate was only 305 m3/s at 12:00 of the same day), and Dak Mi 4 reservoir at 3.349 m3/s (1.416 m3/s). Source: http://plo.vn/thoi-su/hoi-an-va-vung-trung-da-nang-ngap-chim-trong-lu-737631.html