Almost invariably when serious flooding happens, journalists quote a conservationist, NGO representative or government official blaming the disaster on upland deforestation.

One recent example of widely reported claims linking deforestation with severe flooding occurred last October when Hurricane Stan unleashed several days of heavy rain on Central America.

But in a new report titled “Forests and Floods: Drowning in fiction or thriving on facts?”, the Food and Agriculture Organization (FAO), the Center for International Forestry Research (CIFOR) and the World Agroforestry Center (ICRAF) say there is no scientific evidence linking large-scale flooding to deforestation.

“Government decision makers, international aid groups, and the media often blame flooding on deforestation caused by small farmers and loggers,” said Patrick Durst, Senior Forestry Officer for FAO’s Regional Office for Asia and the Pacific. “The conclusion is not only wrong, scientifically, but such misguided views have in the past prompted governments to make life harder for poor farmers by driving them off their lands and away from the forests, while doing nothing to prevent future flooding.”

Although the report acknowledges forests can help reduce the runoff that causes localized flooding, it says tree loss does not significantly contribute to large-scale, widespread flooding. According to Durst, even at the local level the flood-reducing effects of forests are heavily dependent on soil depth and structure, and saturation levels, not exclusively on the presence of the trees.

“Protecting forests can have many benefits, but won’t stop large scale floods,” said CIFOR’s David Kaimowitz. “If deforestation causes floods, you’d expect a rise in major flood events paralleling the rise in deforestation. But the frequency of major flooding has remained constant the last 120 years, going back to when lush forests were abundant.”

The report says the sharp increase in the economic and human losses attributed to flooding is caused not by deforestation but mainly from population growth and increased economic activity. Cities have long been established on flood plains because the benefits of living near water outweighed the risk of flooding. People originally settled on high ground close to flood plains. But as towns have grown, housing estates and commercial zones have moved to the low-lying flood-prone areas. As a result, what were minor floods are now often major disasters.

The report says political expediency may explain why the conventional wisdom about forests and floods remains unchallenged. The myth allows governments to implement logging bans and thus appear to be trying to stop flooding. But in China, Thailand and the Philippines, logging bans have put millions out of work. In Romania, over 1,000 people were recently prosecuted after the country was devastated by flooding.

According to World Agroforestry Centre's Dr. Meine van Noorwdijk “We need to stop blaming people who work near forests for floods that affect entire river basins, and instead consider land-use issues, including poor logging techniques and urban development issues. Policy makers and development agencies should pursue solutions based on the best available science. This is just one example of why agricultural research is vital to reducing global poverty.”

In addition to the FAO, CIFOR and ICRAF, the International Water Management Institute (IWMI) and the International Centre for Integrated Mountain Development also contributed to the report. GC

For the full report, “Forests and Floods: Drowning in fiction or thriving on facts?”

visit ‘Publications’ at CIFOR’s website: http://www.cifor.cgiar.org

For the news release announcing the report, go to ‘Press Room' at CIFOR’s website.