Collection of underground water at the junction of the Lozoya and Jarama rivers

Abstract

The purpose of the arrangement described in this article is to take advantage of the unground water available at the junction of the Lozoya and Jarama rivers, to collect it for the Madrid water supply system. The water is collected by means of two Ranney wells, with radial drainages in metal plates with longitudinal slits. The total length of these slits, for each well, is 500 m. The filtered water is pumped to La Parra Canal, along a steel welded tube, with a capacity of 1 m³/sec. To increase the water pressure on the drainage surface, a small reservoir has been constructed, with moveable Taintor sluice gates and with two lateral spillways. The volume of 1 m³/s of additional water is an important increase in the water supply of Madrid, especially taking into account the short time taken to complete this project and its low cost. The water is of very pure quality, owing to the filtration that it undergoes, both along the river bed and at the collecting wells.