Groundwater exploration for a susutainable supply plan in a rural community: Case cadeate, Santa Elena, Ecuador

Abstract

Manglaralto Water Board (JAAPMAN, for its acronym in Spanish) has been supplying water to Cadeate since 1988, which helps to address the problem of water demand in the area. Water supply in this study area is done by the groundwater exploitation with the wells located in the Manglaralto coastal aquifer, focusing on the water supply to homes and commercial premises linked to tourism. In a shortage of times, water is also distributed through tank trunks, which have a high price and without guaranteeing quality standards. The aim of this study is to identify suitable places for the construction of wells and the consequent development of the exploitation of an aquifer by geological information and geophysical geoelectric tests for the subsurface layer's characterization of the study area and proposal of an exploitation plan of wells in the Cadeate Commune. The methodology is as follows: i) Processing of geographical and geological information of Cadeate, ii) Field survey and geophysical tests to obtain a geoelectric model, iii) Interpretation of results by using specialized software (IPI2Win and RES2DINV) and iv) proposal for a sustainable exploitation plan. Layers of a shallow coastal aquifer linked to the Cadeate seasonal river, approximately 5 to 20 m thick, were identified with detritic material dominated by gravels, sands, with an important presence of silt and clays. These materials permeability reaches the magnitude of 10-3 m/s, and the average porosity is about 18%. A good exploitation plan was established, with a component of the rescue of ancestral knowledge for the establishment of artisanal dikes (tapes) that promote water sowing and harvesting.