HYDROGEOLOGICAL ASSESSMENT OF THE BRITO FORMATION, NICARAGUA

The Brito Formation of Paleogene age blankets a majority of southwestern Nicaragua along the Pacific coast. The marine sedimentary strata outcrop along 75 kilometers of coastline, extend inland as far as 25 kilometers, and are estimated to be greater than 2,500 meters in thickness. The strata and geological structure of the formation support discontinuous, fractured aquifer systems that supply a major portion of water resources for the region. Nicaragua’s Pacific coast has been experiencing sustained growth and development due to tourism, political stability, and lower investment costs compared to other Central American countries. Groundwater resources of the Brito Formation are considered especially vulnerable to negative impacts of overexploitation due to limited recharge and the coastal setting. The reliance upon groundwater resources is increasing significantly along the coast, and water availability has evolved as a major concern to communities, stakeholders and researchers.

In response to community and stakeholder concerns, and documented challenges of finding and sustaining reliable sources of groundwater, a focused assessment included reconnaissance, hydrochemistry analysis, well monitoring, and recharge estimates to better understand the Brito Formation hydrogeology. These data and results illustrate opportunities and vulnerabilities, and the assessment provides an important resource to guide groundwater exploration, planning, sustainable groundwater management, and continuing research.