It is expected that the discharge volume through the spillway will be about 150-200 m3/s. Discharge time is about 1 hour 15 minutes on September 14 and is likely to increase if water from upstream flows to a large reservoir.

Previously, due to technical problems, Bac Ha Hydropower Plant did not operate power generation through 2 units. Meanwhile, due to the long lasting heavy rain, floods pouring into the hydropower reservoir are increasing hour by hour. To ensure safety for the dam body, the plant must discharge floods through the spillway.

Local authorities and Lao Cai province authorities recommend that people living on both sides of the Chay river in the lower reaches of Bac Ha Hydropower need to closely monitor flood developments on the river to take timely preventive measures.