Charging for the use of hydromineral and geothermal resources in Brazil as an instrument of rational use of groundwater

Mineral groundwaters in Brazil are managed centrally by the Federal Union, while other water resources are managed regionally by hydrographic basin. The charging method varies according to the usage and the management system, generating an unbalanced charge on mineral water for bottled water. This study presents a comparison of the charging systems for groundwaters using data for a period of 8 years. The analysis evaluates the efficiency of royalty-based charging of mineral groundwaters against charging over consumption volume for non-mineral groundwaters, taking into account the scale of the producers and their locations. The findings show that the royalty-based system depends on market conditions such as demand, supply and the willingness of the user to pay for bottled water, whilst the volume-based charging system depends mostly on the resource availability and the capacity of the producers to save water. The results demonstrated that the royalty-based charging system favors the production of returnable bottles, with lower environmental impact, as the charge for large returnable bottles is approximately 7 times lower than for disposable bottles. The conclusion is that an integrated management system is required, so proper priorities can be established in the use of groundwaters to benefit the population and to minimize environmental impacts. The successful implementation of integrated management and charging systems are likely to require monitoring and control measures such as automated remote systems for monitoring water consumption, official inspections on consumption and audits on water-saving systems.