The monitoring system covers 99 national groundwater deposits, reservoirs and tail systems, 1,671 w'ells and 43 springs and includes 1,074 observation stations with automatic devices. Also, groundwater extraction is monitored for 7,000 major water users for different purposes (drinking water, industry and irrigation), with the supply network comprising 45,000 wells, 28,800 of which are functioning and pumping 17.7 million m3/ year. Since 2001, the investments in groundw'ater monitoring and exploration have increased by 15-20 per cent per year, all covered by a long-term programme folly funded by the State (chapter 3).