ALTERAÇÃO ANTRÓPICA NA QUALIDADE DOS AQUÍFEROS COLUVIONAR E ITAQUERI NAS CABECEIRAS DO RIO MONJOLINHO, SÃO CARLOS-SP

Anthropic change in the quality of the Coluvionar and Itaqueri aquifers in the upstream of the Monjolinho River, São Carlos, SP

Abstract

In the city of São Carlos, the Monjolinho River, important water supply s source, has its headwaters located in the peri-urban region, with a consolidated urban area, an industrial and a rural area. The phreatic aquifers in the sub basin are important in hydrological dynamics; however, their hydrochemical quality has not yet been investigated. This work aims to understand the impacts generated by anthropic activities on groundwater in the headwaters of the Monjolinho River and for this 28 physical-chemical geoindicators were selected. Water samples were collected from 7 supply wells, in periods of high and low rainfall, with two wells located within the urban perimeter (P26 and P41) and five located in the rural region (P12, P13, P16, P19 and P42). The wells located in the rural area had higher concentrations of the parameters, K and Total P, in addition to Ca. In the urban region, P26 had high concentrations of Na, Cl and N-nitrate, suggesting contamination from sewage, or by the pools located in the surroundings. The study identified interference from urban and rural anthropogenic activities, such as sewage leakage and increase in leachate in groundwater aquifers in the Monjolinho river sub basin.

Keywords: São Carlos, groundwater quality, periurban area, supply source.