Mudflow ) is a sudden rapid flow of water with a high level (up to 75%) of stones, mud, sand, soil.The main causes of mudflows are torrential rains in the mountains, intensive melting of snow and ice in the spring, breakthrough of the dams of mountain lakes, deforestation and destruction of vegetation on the mountain slopes, blasting in the mine workings.
The main factors of mudflow formation are:
- the presence on the slopes of a large number of products of rock destruction;
- large volume of water, contributing to the sliding of these rocks;
- the presence of steep drainage.
Depending on the ratio of components, the following types of mudflows are distinguished:
- water and sand;
When moving, the mudflow is a continuous stream of dirt, stones, and water. The speed of one hundred movement is, as a rule, 15 km / h, the depth of flow can reach 15 m. The duration of the flow may be from 1 to 3 hours.
Actions of the population in case of a mudflow threat
- In areas prone to mudflow processes, anti-mudflow dams and dams are constructed, bypass channels are constructed, land on the slopes is strengthened by planting trees, constant observations are made on the slopes, a warning system is being organized and evacuation is planned.
- Avoid places where mudflows can descend.
- It must always be remembered that a person caught in the mudslide is almost impossible to be saved.
- In case of advance evacuation in the house it is necessary to disconnect the electricity, gas and plumbing; tightly close doors, windows and vents.
After the mudflow flow is over, it is necessary to provide assistance to the victims and assistance to all organs that dismantle rubble and drifts along the mudflow path.