Al Baydha Water System, Part 1: Flash Floods
The most common way to die in the desert is dehydration. The second most common is drowning. Drowning in the desert may seem like an oxymoron, but it illustrates the tricky nature of dealing with water in desert climates; when it rains in a desert, the result is flash floods.
Floods form in deserts because of the lack of foliage. In non-arid climates, plants’ root systems aerate the soil and increase the amount of water the soil will absorb, and the plants themselves slow water flow. Here in the desert, the mitigating effects that plants would normally have on water flow are almost non existent, so the soakage capacity of the land is very low. Moreover, 100% of rain that hits exposed rock becomes runoff. These mountains are almost all rock, so rain gathers speed and power up high, and collects in the wadis, and rushes onto the flood plains, until it reaches the sea. The floods that form in the bigger wadis here in the Hijaz contain billions of liters of water and have enormous destructive power.
More than a few families in Al Baydha have lost loved ones, animals, and farms to floods.
