They can also be obliged to do so if the aquifer they exploit is declared overexploited. The associations establish norms for distribution and control, regulate the use and maintenance of shared hydraulic systems, organise the shared payments and resolve problems among members. They play an important role in the RBAs, to which they assign members in the users’ assembly, which in turn elects at least a third of the members of key decision-making units in the RBAs, including the governing board.