Beavers can help clean polluted rivers and reduce soil loss from farmland, according to a study by Exeter University and the Devon Wildlife Trust.
They looked at a captive colony of beavers in Devon, analysing water before and after it passed through their dams.
They discovered that the dams act as a filter, trapping soil which has run off from farmers' fields, and which contains nitrates and phosphorus from fertilisers..
These chemicals are not allowed into the drinking water supply.
Second swimmer named after Budleigh Christmas swim
The father of two was found at Sandy Bay
New support service for survivors of rape and sexual assualt
Police and Crime Commissioner launches new campaign
Flag removal on one Exeter road could cost £6k
Taking flags down on Bridge Road cost an estimated £6,000
Teignmouth lido to be sold off
Users say it should be kept for the community
Dumped batteries could still cause bin lorry fires
I'm worried that fires could still be an issue'
Stolen telehandler used in Co-op ram-raid
Taken from farm near Plympton
