Heavy rain has battered China since June and is expected to batter more regions.
While inspecting northwest China's Ningxia Hui Autonomous Region, Xi said at a symposium that Communist Party of China committees and governments at various levels should strengthen leadership over flood control and relief work.
He underscored effective organization of rescue teams, relocation and resettlement of people in flood-threatened areas, and supplies.
Those whose dereliction of duty results in heavy casualties and property loss will be held accountable, Xi said.
Xi also highlighted close monitoring of weather changes and rainfall, better analysis of the flood situation, prompt issuance of early warnings, and the timely launch of emergency response measures.
Xi stressed ensuring the safety of important dikes on major rivers, medium and large reservoirs, and key infrastructure, as well as reducing losses near small and medium rivers or due to mountain floods, flooding of cities and typhoons.
Xi demanded utmost efforts to guarantee public safety, including relocating people at risk to safer places, particularly elderly people who live alone and "left behind" children of migrant workers.
Xi ordered relevant personnel to boost emergency response duties and conduct wide-ranging inspections and surveys in order to guard against secondary disasters such as landslides, mountain floods and mudslides.
Officials and the public should be mobilized to participate in flood prevention and relief efforts, Xi said.
The People's Liberation Army (PLA) as well as armed police should "play the role of commandos" in the fight against flood, Xi said, adding localities and departments should support the PLA and armed police in their endeavor.
Xi demanded relevant authorities to start planning for post-disaster water conservation projects, with lessons drawn from problems and loopholes revealed in flood relief efforts in recent years.
Specifically, departments and localities should speed up construction of small-scale water conservancy projects in order to boost flood prevention and disaster relief capacity.
Xi also ordered officials at all levels, especially those in charge, to lead relief efforts at the forefront. He ordered publicity for heroic stories about the battle against floods, as well as honors and rewards for outstanding individuals and organizations.
