The São Paulo Metropolitan Area (SPMA) in Brazil has approximately 22 million inhabitants and consumes an average of 61.6 cubic meters (61,600 liters) of water per second. Although nearly the entire public water supply originates from surface sources, it is estimated that about 18% of total consumption relies on aquifers through approximately 14,000 private wells. Aquifers contribute approximately 347 million cubic meters of water per year.