Haiti: Rivière Grise Diversion Dam – Irrigating 12,350 Acres

USAID’s Global Water Coordinator Christian Holmes
When USAID’s Global Water Coordinator Christian Holmes visited the site of the future dam he was able to stand on ground that during the rainy season is up to 10 feet underwater.

Under the Feed the Future West Watershed Initiative for National Natural Environmental Resources (Winner) program in Haiti, USAID will commit $10 million to build a diversion dam across the Rivière Grise, north of Port-au-Prince, by February 2015.  

USAID’s Global Water Coordinator Christian Holmes recently visited the site and surveyed the future dam’s location.

In the rainy season the river crests the bank, ten feet above the riverbed. The dam will divert water to a channel, which will irrigate approximately 5,000 hectares (about 12,350 acres) supporting primarily beans, maize, okra, peas, plantains, and tomatoes. It will run 400 meters diagonally across the riverbed and use a "sheet pile" structure, consisting of interlocking steel beams pounded down vertically into the riverbed.

At its highest point, the dam will be six feet tall, dropping in height as it connects with the channel. A significant effort will have to be made to periodically clear out the sand, gravel, and rocks accumulating behind the dam. Previous check dams built in the 1950's and 70's to moderate flood waters are now completely underground, covered by accumulated debris.