A farming company has agreed to pay £49,000 towards prosecution costs after being fined for unauthorised work on a stretch of river that harmed the habitat of water voles, a protected species.

Paul Rackham Ltd, based at Manor Farm, Bridgham, pleaded guilty to carrying out works on the River Little Ouse at Lodge Farm Estate, Gasthorpe, near Diss.

A 2.4km stretch of river was dredged and deepened with work also carried out to raise and re-profile the riverbank. Vegetation was also removed.

The firm was last month fined £17,000 at Norwich Crown Court. Prosecutors had sought £63,000 in costs, including towards the Environment Agency investigation, but have now agreed to the lower settlement.

A £400,000 remediation scheme to repair the harm and to reconnect the River Little Ouse to the floodplain has been carried out by the company.

Norfolk flood risk officer, Naomi Daniel, said: “Businesses should ensure they have the correct permits before they carry out work.

“In this case, the actions of the company caused serious damage to the local ecosystem and endangered water voles which will take time to restore.”