|Water tap in La Calera, Valle Gran Rey|
In contrast to some of the other Canary Islands, La Gomera has an abundant supply of water. While the many open reservoirs are exclusively used for irrigation of the crops in summer, nearly all the drinking water and the domestic supply comes from wells and springs that produce water of excellent quality. Rainfall replenishes these, but the forest that covers the top of the island produces additional water when the mist and fog that are carried across the mountains by the trade winds condensate on the trees and percolate through the ground to feed the springs.
However, the past winter brought very little rain to La Gomera and a recent survey revealed that half of La Gomera's drinking water available through the public water supply is lost and wasted because of an ageing and often faulty infrastructure. Measurements have shown that there are numerous leaks between source and households. The town of San Sebastian is now introducing 2.500 pressure reducing valves and diffusers in a measure which is expected to save 44.000 litres of precious water per day.
Other towns like Valle Gran Rey have also begun to replace old and leaking pipes, but it will take a long time until the full amount of water entering the distribution system will actually be contained within the grid and available to consumers.
The water survey included water reservoirs and it was found that agriculture uses 82% of all available water, while about 18% is for human consumption, including the 6,3% used by the tourism sector. More than three quarters of all available water on the island of La Gomera comes from underground sources.
The island's capital San Sebastian is the only town so far which uses treated and purified waste water for the irrigation of its public parks and green areas, saving 0,6% of all available water.