Assessing the Return Periods and Hydroclimatic Parameters for Rainwater Drainage in the Coastal City of Cotonou in Benin under Climate Variability

Table 1

Flood records in Benin and their impacts during the last four decades.

Year	Hazard	Regions	Impacts/damages
1985	Floods	Mono, Zou, Borgou-Alibori, Ouémé-Atlantique	61 people were reported missing; 11637 houses, 651 schools, 2704 km of roads, 201 bridges, 17412 ha of farmland, 7937 tons of cereals, and 5421 heads of cattle were destroyed
1988	Floods	Zou, Borgou-Alibori	270,000 people affected, 2706 km of roads, 30,000 ha of farmland, and 25,000 tons of grain destroyed, and livestock lost
1991	Floods	Zou, Atlantique, Littoral	700,000 people were affected and 556 ha of farmland destroyed
1994	Floods	Borgou-Alibori	4600 destroyed houses and roads, 19000 ha of farmland flooded, loss of livestock
1996	Floods	Zou-Collines	147,901 people affected, roads destroyed, 1544 ha of farmland flooded, 893 tons of agricultural production lost, significant loss of livestock
1997	Floods	Atlantique, Ouémé, Mono	Destruction of houses, farms, and roads
1998	Heavy rainfall	Ouémé	Flooded farmlands
2001	Thunderstorms	Littoral	The capsizing of two boats on Lake Nokoué with loss of life
2002	Thunderstorms	Mono	Destruction of the roof of three classroom modules
2003	Heavy rainfall	Littoral	Flooded roads
	Thunderstorms	Mono	13 flooded schools
2004	Thunderstorms, floods	Littoral	Flooded roads
2005	Thunderstorms	Littoral	Houses destroyed, neighbourhoods flooded
2006	Thunderstorms	All regions	Houses destroyed, neighbourhoods flooded
2007	Thunderstorms, floods	Littoral, Mono, Northen-Benin	3476 people were affected, 1382 buildings and 5459 ha of farmland destroyed
2008	Floods	Ouémé	5 deaths, 15498 ha of farmland lost, 3190 animals dead, 17 schools and clinics flooded
2010	Floods	55 municipalities were affected to varying degrees (out of 77 in the country)	46 deaths; 680,000 people affected, of whom 150,000 needed shelter; more than 55,000 damaged houses, 455 schools and 92 health facilities partially or completely destroyed
2011–2015	Floods	All regions	25 deaths; 215 hospital admissions, 11652 houses affected, 46871 people made homeless, 140287 ha of farmland and 37339 animals lost, 259 storage units destroyed, 119 schools affected

Source: ABV-OMM-GWP initiative volta GIC [19].