Some Information on the Watersheds of the Massacre and Marion Rivers - Northern Border Extremity of Haiti/Dominican Republic

This technical report provides comprehensive information about the Massacre and Marion river watersheds located in the northeastern department of Haiti along the Haitian-Dominican border. The Massacre River watershed covers 382.7 km² with a Gravelius index of 1.49, indicating an elongated basin shape, while the Marion watershed covers 197 km². The document details the hydrographic networks, geological formations, and environmental challenges facing these border regions.

The report examines the complex geological composition of both watersheds, including sedimentary rocks (marl and sand, hard limestone, flysch) and magmatic rocks (andesite, rhyodacite, basalts). It addresses critical environmental issues including deforestation, land degradation, and soil erosion that particularly affect the Haitian side of the border. The document highlights how deforestation leads to rapid water erosion, reduced water absorption capacity, and alternating floods and droughts.

Significant socio-economic challenges are documented, including food insecurity in Haitian communities and widespread involvement in charcoal production, with 28% of households in the Massacre watershed engaged in this activity. The report notes population growth in border towns like Ouanaminthe, which has experienced 20% annual growth. Land tenure issues are also addressed, noting that most Haitian lands officially belong to the state but lack proper cadastral systems.

The hydrogeological analysis reveals diverse aquifer systems including alluvial aquifers, karstic limestone, and carbonated limestone formations with varying productivity levels. The document serves as a baseline study for disaster risk mitigation planning in these vulnerable border watersheds.