Avaliação da intrusão salina nos poҫos dos bairros (Inhangome, Chuabo Dembe, Manhaua A e B, Icidua, Namuinho e Bazar) município de Quelimane

Abstract

Saline intrusion in wells is a phenomenon that occurs when salt water penetrates the freshwater aquifer, compromising its quality and potential use. This problem is particularly relevant in coastal regions, where the proximity of the ocean facilitates the displacement of salts to underground aquifers. This study aims to evaluate the saline intrusion in wells in the neighborhoods of Inhangome, Chuabo Dembe Manhaua A and B, Icidua, Namuinho and Bazar, Quelimane Municipality, quantify the salinity and electrical conductivity content of the water in the wells, identify the neighborhoods with the greatest influence of saline intrusion in the wells, and establish a relationship between salinity and electrical conductivity. Aiming at this, 35 water samples were collected, 5 samples for each neighborhood, in a total of 7 neighborhoods in the Quelimane Municipality. The samples were subjected to determination of salinity and electrical conductivity content and the depth of the wells in relation to the earth's surface was considered in order to relate the contents and depth. The results obtained indicate that all 35 water wells monitored in 7 neighborhoods contain salinity levels above the standard recommended by the WHO, for the electrical conductivity parameter about 8 water wells present levels recommended by the WHO, where 2 water wells were registered in Inhangome, 3 wells in the Chuabo Dembe neighborhood, 1 in Bazar and 2 water wells in Namuinho, and 27 water wells present electrical conductivity levels above the standard recommended by the WHO. The salinity levels in all neighborhoods range from 0.21- 12.99 PPT and the conductivity levels range from 0.63 - 19.99 mS/cm. The districts with the highest salinity levels are Icidua, Manhaua A and B, Inhangome, Namuinho and Bazar, while the district with the lowest level is Chuabo Dembe. For electrical conductivity, all districts have wells with extreme levels. Consumers are advised that drinking water with high salt concentrations can cause cardiovascular problems.