The layout-Carholm Landslides represent a complex series of landslides that achieved climatic proportions in 1997 and remain a hazard today. The Layou River is one of the largest watersheds in Dominica and drains about 10 % of the land.
Landslides were common in the area, with specific reports occurring between 1987 and 1997. There is an eyewitness account of a slide following Hurricane Hugo in 1989 and also following Hurricanes Iris, Luis and Marilyn in 1995. There was a major change to the pattern of small landslides. Dramatic slumping occurred between November 18 and 25, 1997. Two major slides blocked the river and created a natural dam. The dam was breached on November 21 with mudflows reaching the sea accompanied by extensive flooding of the lower river valley. A wall of material estimated at 50 feet high was washed downstream. An estimated 300 million gallons of water had collected behind the natural dam wall, at a depth of 60 feet and ¾ of a mile in extent. The riverbed rose dramatically in its lower reaches. This elevation was estimated at 30 feet at the location of the swing bridge. The river had dried up between November 18-20 1997 and then flooded on November 21. Further landslides occurred on November 25, 1997 and October 8 and 11, 1998 with subsequent dam breaks being significant events.
Socio-Economic Impact
Temporary evacuation of 600 residents
Loss of an access road to banana producing areas
Closure of Layou Valley Hotel
Loss of Swing Bridge
Loss of income through fisheries and tourism related sales
Severe disruption of traffic
Agriculture, Forestry and fisheries impact
Loss of approximately 40 acres of land
Loss of natural vegetation
Loss of bananas and tree crops especially citrus and cocoa
Destruction of cocoa crying shed and banana boxing plant
Siltation of river and buildup of sediment offshore
Pot fishery has been destroyed in the area
Fish sales have fallen away dramatically
Fishermen have been dislocated many must now use other landing sites
Reefs located two miles offshore are covered with mud
Aquatic life in the river was obliterated
Loss of streamside vegetation
Source: https://goo.gl/MN48Bh