The engineering geology assessment of Belle Fontaine Road in Haiti was conducted by Joe Dunbar, Research Geologist, Geotechnical Laboratory, US Army Engineer and Development Center, USAE Waterways Experiment Station, Vicksburg, MS. The site visit took place from January 31 to February 4, 2000, in support of the US Agency for International Development (USAID), Haiti, Economic Growth Office, and their contractors as part of the US Army Corps of Engineers (USACE) Participating Agency Support Agreement (PASA) initiated in 1999 following the destruction caused by Hurricane Georges.
The purpose of the assessment was to provide engineering geologic support to evaluate alternatives for the Belle Fontaine road, assess landslide hazards for the proposed route, and make recommendations for mitigating existing slides on the road. The scope of the study was limited to a brief review of available geologic data, a site reconnaissance of the Belle Fontaine area, and participation in several meetings with USAID and their support contractors. The focus of the meetings was to review road alternatives and evaluate preliminary design specifications for the final route.
Improvements to the existing road were considered to be more cost-effective in the short term than extensive construction required for building a new road from the ridge crest to the river crossing at Trois Passes. Costs to improve the existing roadway will depend on the final engineering design, which is scheduled for completion by the engineering contractor at the end of February. The potential for landslide activity in the Belle Fontaine area is significant due to mountainous terrain and lack of vegetation on steep slopes resulting from deforestation.
Past landslide activity was identified approximately midway in the Riviere de l’Est Valley, where the coarse texture of river bed sediments and absence of any debris at the base of the rock face indicate high energy conditions within this part of the Riviere de l’Est Valley. The contractor has identified this unstable area in their engineering study and has routed the road away from this part of the river valley. For the mountain and mission segments of the road, rock falls are a major hazard to motorists and pedestrians, and control of surface drainage is essential to prevent further erosion of the roadway and the slopes upon which the road is constructed.