Ricardo Hirata
Groundwater + Megacities = a Brazilian perspective
Abstract: Although Brazil is the 9th largest groundwater user globally, the perception of its importance is still little recognized by society, due to the factors: (i) most of the groundwater extraction (82%) is carried out by private wells; (ii) illegal wells are greater than 70-80%; (iii) the training of water resources managers rarely considers hydrogeology, and (iv) fundamental and secondary schools do not teach hydrogeology. Groundwater is also invisible to official statistics. An example occurs in the Metropolitan Region of São Paulo (21.5 million inhabitants), where only 1% of the public water supply is provided by groundwater. However, 13,000 private wells extract 11 m3/s and supplement the water demand, increasing the population's dependence to 18%. This reality shows that a single and centralized city water supply must be rethought, especially in an environment of low financial investment. Traditional water management sees private users as a problem or a competitor to public utilities, but new Brazilian cities must consider them as partners and as part of the water crises solutions.
