Flash floods appear where little rain has fallen and, having directly interacted with the land elsewhere, move great quantities of earth as well as water. Flooding tends to modify the landscape in ways impossible for humans to conceive, and do so beyond human control. Violent rain events are associated with lighting and wind, also powerful forces. Water can disappear and reappear many miles away, giving evidence of its willful nature. Water-Canyons Become Regions of Refuge.
Water creates places, which are difficult to gain access to like deep canyons and hanging valleys.
During the historic period such places were sought by Indian groups who were elsewhere stressed by Euroamerican encroachment into more accessible areas. Geographically inaccessible areas only became regions of refuge when sufficient water was presence to sustain the lives of the Indian groups. Water Creates Riverine Oases . Rivers begin where there is abundant rainfall but then flows for hundreds of miles into and through arid regions. Rivers can create ribbon oases which sustain life for plants and animals that otherwise could not be in the more arid region.