JOHANNESBURG, 21 January 2011 (IRIN) - Heavy rains and localized flooding across southern Africa from Angola to Madagascar are raising fears that the devastating floods of 2000 will be repeated. Then, thousands of people were plucked from rooftops by helicopter, several hundred died, and Mozambique's agricultural production was severely impacted.

"All countries in contiguous southern Africa are expected to receive normal to above-normal rainfall between January and March 2011 - northern Zimbabwe, central Zambia, southern Malawi, central Mozambique and most of Madagascar are expected to receive above-normal rainfall," said an update by the UN Office for the Coordination of Humanitarian Affairs (OCHA), published on 20 January.

Hein Zeelie, an OCHA humanitarian affairs officer based in Johannesburg, South Africa, told IRIN that across the region water levels in rivers were "very high", but at this stage "you cannot compare the current situation to previous flooding in Mozambique."

In the past decade, "a lot had changed" in southern Africa, he said. There was greater coordination between governments, and countries were much more prepared for dealing with flooding.

Part of these precautions was the regular release of water from the Kariba Dam on the Zambezi River in Zimbabwe, and the Cahora Bassa Dam further down the river in Mozambique, to reduce the risk associated with suddenly having to discharge a large volume of water. The Zambezi River Authority (ZRA) was planning to open "two spillway gates of Lake Kariba on 22 January 2011", OCHA noted in its flood update.

"This ... may result in rising water levels and, in time, possible flooding further downstream. The Zambian government has already issued flood warnings to districts adjacent to the lower Zambezi River, and district disaster managers are alerting communities and preparing for possible flooding. Zambian authorities have informed those in Mozambique of this decision," OCHA said.

The Zambezi River, the continent's fourth largest, rises in Zambia and flows through Angola, along the borders of Namibia and Botswana, and into Zambia again, then along the Zimbabwean border and through Mozambique, where it reaches the Indian Ocean about 150km north of the port city of Beira.

Cyclone season

Zeelie said the cyclone season, which begins in January and runs through to March, was an added threat. So far there had been no cyclones, but these weather systems "usually pick up in February", and "they [cyclones] are the main drivers of devastation."

In 2000, torrential rains had been falling across Mozambique since 8 February when tropical Cyclone Eline made landfall near Beira on 22 February. Five days later flash floods overwhelmed low-lying farmlands and there was wide-scale flooding in the capital, Maputo.

"Historically, the rainfall will increase during the period of end-January to end-February (March in some countries), and this is when major rivers increase their levels and flood low-lying areas, mainly the most productive agricultural areas," the southern Africa office of the International Federation of Red Cross and Red Crescent Societies (IFRC) noted in a recent report.

"Lessons from the Mozambique floods in 2000 are relevant, as most of those floods were caused by flash water released through the major regional rivers. Monitoring the situation and strengthening disaster prevention measures in the next six weeks is critical ... to prevent a possible escalation of floods into a regional disaster," the report warned.

"Tens of thousands of people could be displaced or evacuated, and hundreds of thousands more could be affected by damage to crops and shelter."

Farid Abdulkadir, Disaster Management Coordinator at IFRC, told IRIN that volunteers had been placed on high alert, and emergency stocks, including shelter, blankets, chlorine tablets and mobile water purification plants, had been prepositioned throughout the region.

"Compared to 2000 the [disaster response] system is much better prepared, but we fear the situation will be quite intense."

Unlike other countries in the region, Abdulkadir said, Mozambique faced "triple disasters occurring at the same time", with water flowing down rivers – such as the Zambezi and Limpopo, which disgorges into the sea near Xai-Xai – as well as rainfall over the country and cyclones from the sea.

Heavy regional rains

In South Africa, weather-related incidents, including floods, lightning strikes and tornadoes, are thought to have killed 40 people
between mid-December 2010 and 17 January 2011, and more than 6,000 people had been displaced, according to the National Disaster Management Centre.

Heavy rains in Lesotho caused crop damage, and four people died in a landslide. In Madagascar, local reports said heavy rainfall in the
southern city of Tulear on 6 January 2011 resulted in the death of two people.

The Angolan media reported that 11 people died in flash floods in the northern province of Luanda, and said more heavy rain was expected.

OCHA Zambia Disaster Management Team met recently "to discuss the flood situation, and will be providing a brief on preparedness activities shortly. These activities will include mitigating the chances of cholera outbreaks."

In the past two weeks, heavy rains have fallen across Zimbabwe, and "there have been isolated reports of flash floods in some parts of the country, but no major floods as yet," OCHA said in its report.

However, "There are indications that water levels in most rivers and dams are rising, and that many dams, particularly in the north, are nearing capacity."

Source: The Integrated Regional Information Networks (http://www.irinnews.org )