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.
Axminster children connect with space station
Space cadets link live with astronaut
East Devon should get new CEO
Local Government Association recommends new boss
Long-serving County Council leader steps down
John Hart leaves after 15 years
Football club changes kit to honor former player
Exeter Royals' tribute to young star
Crime Commissioner reveals top priorities
What is the force's next goal?
Torbay MP explains why he didn't vote on smoke ban
He says adults should be able to make up their own minds
