Major floods in late 2008 and 2009 have plunged southern Africa into a growing humanitarian crisis, killing dozens and displacing thousands.

The Zambezi River Basin is affected annually by floods, bringing death and disease to those living along the banks. The fourth largest river in Africa, has its source in Zambia and flows through Angola, back into Zambia, and along the borders of Namibia, Botswana and Zimbabwe to Mozambique, where it empties into the Indian Ocean.

With no sign of a let-up in the rainy weather, there are growing fears the flooding could worsen in the coming weeks and devastate the region's largely agricultural-based economies in the middle of the critical summer growing season. The floods also raise the threat of outbreaks of malaria and cholera.

By mid-March, the Zambezi River in northeast Namibia had risen to an alarming height of 7.82 metres (25.7 feet) at Katima Mulilo town - the second highest level in 40 years, according to Namibia's national paper The Namibian. The highest record for the Zambezi was 8.16m in 1969, according to the Ministry of Agriculture.

Namibia's president has declared a state of emergency in the north central and northeastern regions, and warned of food shortages. Many of the more than 200,000 people affected are subsistence farmers already recovering from serious floods in early 2008 which destroyed crops and homes. The north central region is affected by heavy rains in southern Angola and Namibia which have turned local rivers into raging torrents.

In Angola, at least 30,000 people have been made homeless. Government figures say 90,000 hectares (222,000 acres) of land has been destroyed. The Red Cross says more than a dozen people have died, many of them in the southern province of Cunene where more than 75,000 people have been affected.

In neighbouring Zambia, officials say the country may be facing its worst floods in 40 years.

In January 2008, Zambia declared a national disaster after floods swept through the landlocked nation and several neighbouring countries, killing at least 45 people and destroying roads, bridges, crops and livestock. This year's flooding has already damaged crops and roads.

Parts of Zimbabwe have been affected by heavy rains since December 2008 that have worsened the country's cholera epidemic.

Rains have also pounded parts of Malawi and Mozambique displacing thousands and drowning farmland.

Mozambique is flood-prone. U.N. agencies have warned the flooding there could be worse than in 2000-2001 when over 700 people were killed and hundreds of thousands left homeless. Up to 300,000 people in river communities throughout central Mozambique were affected by flooding in early 2008, with 29 killed.

Every year in Malawi villagers living along the flood plain of the Shire river - the country's largest - risk losing their crops and their homes, and 2009 has been no different. At least 2,100 families have been affected since the Shire burst its banks due to heavy rains.

Heavy rains in Zambia, Mozambique, Zimbabwe and Malawi have caused several swollen rivers to burst their banks, forcing thousands of villagers to flee flooded homes. Panicked residents have drowned or been killed by crocodiles as they attempted to cross rivers for higher ground.

Heavy downpours are common in southern Africa in the rainy season, which runs generally from November to April.