La Palma - Water Tunnels

Water Tunnels

The most famous structures of La Palma are the minas galerias (water tunnels) which carry the water from sources in the mountains to cities, villages and farms (mainly banana plantations). La Palma receives almost all of its water supply due to the mar de nubes (sea of clouds), stratocumulus cloud at 1200–1600 m altitude, carried on the prevailing wind which blows from the north-east Trade Winds. The water condenses on the long needles of the trees and other vegetation, it then either drips onto the ground or runs down the trunk etc., into the ground. Eventually it collects inside the rock-strata, and is then drained via the galerias into aqueducts and pipes for distribution. The galerias have been cut into the rocks over centuries. To visit the galerias a permit is required. It is possible to walk alongside many of the aqueducts, a popular activity for tourists (similar to the levadas of Madeira). The tour to the Marcos y Corderos waterfall and springs is also popular.

There is an extensive network of irrigation canals in the valley of Los Llanos de Aridane. These canals carry water from the mountains throughout the valley and allow for the cultivation of bananas, avocados, flowers, and other plants. Each farmer gets a scheduled "turn" to fill an irrigation tank with water 24 hours of the day. If a farmer's turn is at 2 AM he will wake up and make sure to fill his tank when possible so as to have sufficient water for his farm.

These round tanks typically gather moss and lilly pads upon which frogs make their habitat.