Rivers reach flood levels in Port-à-Piment

Heavy rains in the watershed of Port-à-Piment early the week of April 23rd have led to flooding of the river systems. Rain gauges located in the towns of Randel and Port-à-Piment have collected data on the recent rainfall that accurately capture the weather patterns behind the flooding experienced on the ground. Staff of the Port-à-Piment Millennium Village Project and partners are monitoring for flood damages, including crop loss and increased cases of cholera, in the first major flood event of the 2012 rainy season.

Flooding occurred in Port-à-Piment through Tuesday. Floodwaters arriving in Port-à-Piment are murky, carry erosion-causing sediment from the upper regions of the riverbeds, which in turn create cloudy discharge into the mouth of the river as it meets the sea.

The rain event, which began around midnight on Monday, April 23rd, produced an accumulation of 5 inches of rain in the town of Randel in the upper mountainous region of the watershed. The sea level of Port-à-Piment at the base of the watershed, by contrast, accumulated only 1.2 inches of rain. The discrepancy in precipitation levels based on elevation is a regular occurance based on the topography of the region, with heavy rainfalls in the upper regions often resulting in severe flooding in the towns along the river at lower elevations.

The intensity of the rain in Randel experienced on Monday night was the at the same level of that of the floods in October of 2011, which accrued a total of 14 inches of water in the town of Port-à-Piment over the span of three days. The three days of sustained rain in October 2011 caused massive flooding and resulted in an increase in obsered cholera cases and isolation of several communities in the Côte Sud region. Though not as severe, the flooding observed on Monday and Tuesday in Port-à-Piment demonstrates the need for increased flood protection and early warning systems in the region, as the potential for isolated weather events causing flooding remains high. Soil moisture in the town of Port-à-Piment remains at an elevated level; saturated soil levels also increase the risk of flash flooding, as the penetration rate of water indicates the amount of possible runoff that causes flooding and erosion of river banks.

The month of April marks the beginning of the rainy season in southwest Haiti, coinciding with the hurricane season throughout the Caribbean region. The increase in precipitation causes a period of increased vulnerability for the majority of the residents of the Côte Sud region and the Port-à-Piment watershed. Residents rely primarily on agricultural crops for household income, which due to the steep topography and the instability of the hillsides are often in danger after heavy rains. Responding to agricultural assessments made with the ict4Ag mobile-phone based tool, 48% of farmers indicate that flooding would reduce the yield of their most important crop by at least 75%; 43% of farmers say that flooding would impact at least 50% of the yield of their most important crop. Additionally, the rainy season also exacerbates preexisting risk factors associated with water, particularly water-bourne diseases like cholera.

The rain gauges, along with river monitoring systems recently installed by researchers of the Earth Institute throughout the watershed, are part of the Port-à-Piment Millennium Village’s efforts to obtain real-time climate data on weather events such as these, which can in turn be utilised to develop accurate climate and flood modeling systems. Throughout the 2012 rainy season, weather event from heavy rains to high winds will be monitored and integrated with public health monitoring and socio-economic data to produce a disaster-risk reduction strategy for the Port-à-Piment watershed.