At some point, the dike had sunk by more than 250 m. Specialized agencies have determined that the occurrence of subsidence is due to the steep terrain, weak geology, and severity of flooding. Over the past 50 years, the dike has eroded a number of times but there have been no permanent solutions. Heavy rains are expected to continue in the coming days and the flow of water from the upstream area will continue to rise. Due to this, subsidence in Phu Tho province is likely to continue.
