Basic physical and mechanical properties of mountain torrents

As a special flood phenomenon, mountain torrents have different motion and dynamic characteristics than ordinary floods. Rainstorm and mountain flood have the characteristics of fast current velocity, high sediment content, large destructive power, steep water potential, and short duration.

The motion characteristics of mountain torrents

Mountain torrents occur in smaller basins. Under the impact of strong rainstorm, water converges fleetly and forms mountain torrents, reaching the highest water level quickly. The rising time of the flood is shorter than the falling time; the maximum flow velocity is basically the same as the time of the highest water level, and the flow velocity when rising is greater than that of the falling. The loop curve is presented on the water level flow chart. There are typical figures of mountain flood flow process line and water level and velocity line.

Avoid the risk of mountain flood

Mountain torrent is sudden floods in a gully. It has the characteristics of sudden, concentrated, and destructive and so on. Therefore, once you are in a mountainous area, do not panic and try to listen to command of experienced people, immediately looking for higher ground to avoid disaster. Run away in the direction of ridge and don’t avoid the flood under dangerous rocks and unstable boulders. Do not linger in the valley, for the valley is the path of the mountain torrents.

When you meet the mountain floods, you need to do the following:

• Be sure to keep calm and move quickly to the mountains or highlands; if it can't be transferred for a moment, choose a relatively safe place at the same time while observing the environment behind it.

• When a flash flood occurs, do not run down the hillside slope or the valley exit. Choose a near safe route to run along the hillside.

• Mountain torrents are swift and violent, with high speed and fast speed. Do not cross the river lightly.

• When trapped by mountain torrents, it is necessary to get in touch with the flood prevention department of the local government immediately and seek assistance. We must listen to the arrangement of the personnel concerned, and at the same time, in case of emergency, we should learn to send out distress signals, such as shouting for help or shaking clothes.