What conditions are necessary for mudflows?

For the occurrence of mudflow, the simultaneous coincidence of three mandatory conditions is required:
The presence on the slopes of the mudflow basin of a sufficient amount of easily transported rock destruction products (sand, gravel, pebbles, small stones);
The presence of a significant amount of water for flushing from the slopes of stones and soil and their movement along the channel;
sufficient steepness of the slopes (at least 10-15 °) of the mudflow basin and water flow (mudflow channel).