Bring back beavers to control flooding, environment secretary told

The cheapest and most effective way to control river flooding in Britain would be to bring back beavers to construct natural dams to hold back water, the UK Mammal Society has recommended to the environment secretary, Owen Paterson.

The rodents, known as "master river engineers", nibble and fell trees to create large lodges which restrict river flow, store water, and reduce flash floods and erosion. The UK has been lashed with storms and flooding in the past two months, with the south-west particularly badly hit, and David Cameron saying on Wednesday that it is unacceptable that parts of Somerset are still underwater.

Marina Pacheco, the society's chief executive, said: "We urge the government to consider a bold and cost-effective wildlife solution: bring back the beaver and allow it to apply its benign engineering skills to our river systems. Our waterways are fed by man-made ditches and field drains that reduce the land's natural ability to hold water. Excessive flooding of towns, villages and farmland in the lowlands is the inevitable consequence of this unnaturally rapid transfer of water from the hills."

The government is known to be considering paying farmers to hold back water in the uplands, but this, said Pacheco, could cost millions of pounds per year. "The beaver could achieve the same effects for free and forever if we are bold enough to re-establish and tolerate it as a natural component of our river systems," she said.

Beavers were native to Britain but were eradicated by landowners seeking to protect their fish and trees, hunters wanting their fur and by centuries of river straightening by government which destroyed their habitats.

Many other countries have reintroduced beavers successfully but Britain has been extremely cautious following landowner opposition. One trial reintroduction is nearing completion in Knapdale, Scotland, an 'unofficial' population has been established on the river Tay in the southern Highlands.

Plans for a reintroduction in Wales are at an advanced stage. Several English groups want to re-establish colonies but will have to wait for a full assessment of the Knapdale trial. There was a recent sighting of what appeared to be a beaver in the wild in Dorset, photographed by a retired environmental scientist.