Groundwater mapping using DC resistivity in Leogane, Haiti

The residents of Leogane, Haiti have historically relied on shallow hand-excavated wells as a source of water. Following the 2010 Haiti Earthquake, a cholera outbreak occurred in Leogane. Cholera is exacerbated by excessive amounts of standing water, so the streets in downtown Leogane were paved and a strom water drainage system was constructed to reduce surface water and mitigate the cholera. However, many of the wells, some of which had been productive for centuries, dried up and it was hypothesized that the new pavement and drainage system disrupted groundwater recharge in Leogane. To address this issue, a study was performed to evaluate groundwater conditions in Leogane so that existing wells cold be remediated and new wells could be constructed appropriately. This study was performed in February 2018 with the support of the Society of Exploration Geophysicists Foundation Geoscientists Without Borders. The groundwater study included surveying and sampling of shallow water wells and electrical DC resistivity testing throughout Leogane to evaluate water quality and estimate the depth to the water table. This study revealed the presence of two aquifers, including a shallow (0-12 m deep) unconfined aquifer containing coliform-impacted water and a deep (> 15 ft deep) confined aquifer containing clean water. It was also concluded that the presence of the pavement and storm water management system did not impact groundwater and fluctuations in well performance are most likely due to seasonal variations. The results of this study will be disseminated to the public through local authorities affiliated with the Catholic Church and will be used to provide guidance for future water well remediation and development activities.