News: Sole wild beaver colony threatened by sewage spills

Since their reintroduction by the Devon Wildlife Trust six years ago, beavers have begun to thrive on the River Otter. However, sewage being discharged weekly from a storm overflow site upstream has the potential to cause the colony of about 20 families serious health problems, wildlife experts say.

The overflow site at Honiton, Devon, spilt 137 times last year, totalling 2,442 hours of spillage. The spill site, operated by South West Water, flows directly into the Otter. The water company was approached for comment.

Mark Elliott, who oversees the beaver project, said that the discharges were a massive concern. He added: “There is a whole range of nasties contained in sewage that could potentially impact them, like viruses and bacteria.”

Overflows usually occur during heavy rainfall as a “release valve” to prevent sewers from flooding. Effluent is diluted with rainwater but remains untreated, introducing contaminants and pathogens into the water that can cause toxic blue-green algal blooms.

Beavers became extinct in England in the 1500s. Their proposed reintroduction, which is out to consultation, forms part of the government’s 25-year environment plan, published in 2018. Beavers’ dams can reduce pollution and boost wildlife populations, a study from Exeter University shows. Dams mitigate the impact of flooding.

The Lower Otter valley is undergoing a £15 million project to restore natural floodplains and create 55 hectares of mudflats, saltmarsh and other habitats. The project is funded by the EU and the Environment Agency.

Dr Nicola Daniel, former chairwoman of the Otter Valley Association, said: “I find it quite extraordinary that we have had £15 million spent on the estuary and no work being done on the pollution levels.”

Raw sewage spills were a key reason why 84 per cent of rivers and lakes in England failed to meet the government’s target of good ecological status last year. Threatened with a backbench revolt, ministers have tabled an amendment to the Environment Bill, which will force water firms to ensure a “progressive reduction in adverse impacts of discharges from storm overflows”.

Source: The Times Online, by Tom Ball