Groundwater resources of Parnamirim region, RN: water use and potencial

Abstract

The study area is within the Pirangi River Basin, situated in the state of Rio Grande do Norte, Brazil, covering about 370 km², where is located Parnamirim city. Urban expansion in the municipality of Parnamirim occurs under accelerated rates, and it takes place under no proper infra structure, notably by the lack of sewage networks, presenting high risks for groundwater contamination. Groundwater consists on the main source of water to supply urban and rural demands. The main purposes of this study were to quantify the use and evaluate the potential of groundwater in the area, considering the requirements of good quality water supply preventing the possibility of risks against human activities. During this study an updated register of wells and a characterization of the hydrogeological framework of the area were carried out, followed by the assessment of hydraulic parameters of the aquifer and the groundwater flow behavior. The saturated thickness of the Barreiras Aquifer System increases from West to East, presenting values ranging from 15.47 to 56.5 m (average of 32.45 m). The hydrodynamic parameters were estimated based on the interpretation of pumping tests, which provided transmissivity average 5.9x10-3 m²/s, hydraulic conductivity average is 2.82x10-4 m/s and specific porosity average of 15%. Groundwater flow direction is generally from West to East, allowing the recognition of recharge and discharge areas. Recharge was estimated to be about 253 mm/year, which corresponds to an infiltration rate of 16.4% of the precipitation

Keywords

• Sistema Aquífero Barreiras. Desenvolvimento urbano. Potencialidades Hidrogeológicas.