Zimbabwe has appealed for $100m (£82m) to help those hit by floods that have killed 246 people since December.
Officials say floods, which follow a crippling drought, have swept through villages, destroying roads, crops and livestock in the south of the country.
The air force has transported some marooned villagers to safety.
Last week the cash-strapped government was criticised for reportedly spending up to $2m to celebrate President Robert Mugabe’s 93rd birthday.
Mr Mugabe has declared the floods a national disaster.
Around 2,000 people have been left homeless by the flooding, with a further 1,500 described as “marooned”, in an official government briefing, with communities cut off by the damage to roads.
Five bridges on major highways have been swept away, Transport Minister Joram Gumbo told local media.
The deadly floods have compounded the problems facing many Zimbabweans, who are still reeling from the affects of a crippling drought.
More than four million people are estimated to be in need of food aid after rains failed last year.
In what the government calls “an astounding shift from a drought condition to an excessively wet situation,” it lists 10 provinces, mainly in the south and west of the country, which have been worst affected by the recent flooding.
Public infrastructure has been badly hit with 74 schools damaged, Minister for Local Government Saviour Kasukuwere said.
Seventy dams had burst and 85% of the country’s dams were full, meaning that “even low amounts of rainfall will cause flooding,” he added.
Zimbabwe hit by deadly floods after drought