Description
The city of Gonaïves is the capital of the Artibonite department of Haiti. It has a population of about 300,000 people. It is situated on a flat plain on the coast, with a small river La Quinte running past it (see Figure 3.17). During most of the year, all the water in this river is used for irrigation. However, after heavy rainfall, the small La Quinte stream can swell and overflow its banks to run through the surrounding lands including the city of Gonaïves. Moreover, if at the same time, the sea water level is high, the water accumulates near the coast and the city is severely flooded. In September 2004, Hurricane Jeanne caused major flooding and mudslides in the city. Four years later, the city was again devastated by another storm, Hurricane Hanna, which again flooded parts of the city and killed 529 people.

A modelling chain was developed to simulate storm surge, rainfall runoff and flooding of the city of Gonaïves, as a result of a hurricane storm passing by. The end user defines a hurricane track by a series of coordinates of the eye of the storm and a maximum wind velocity. This information is transformed into a time dependent wind field by WES and into a rainfall field by the R-CLIPER module. The wind field is input to a Delft-3D storm surge model of about 1500 by 1500 km (resolution of 5 to 6 km, bathymetry from GEBCO2008). The rainfall field is input to a Wflow hydrologic model, which covers the watershed of the La Quinte River and neighbouring streams at a resolution of 100 m. The DEM for this model was derived from TanDEM-X.

An exmple of flooding map in Les Gonaives – Haiti.