A Taunton potato farmer has been prosecuted by the Environment Agency for causing silt, soil and potatoes to escape from a field and seriously pollute a tributary of the River Tone in Somerset.

David Mitchell, of Hillcommon in Taunton, Somerset appeared before Taunton Magistrates Court on 18 June 2025. Mr Mitchell pleaded guilty to an offence of causing silt laden water from a field under his control at Combe Florey to enter a stream on two occasions in August and again on September 2022.

The judge found that the pollution was so significant in that it would take a winter of normal water flow to wash the sediment away.

He was given full credit for his guilty plea by the District Judge and fines and compensation were ordered to be paid within 12 months. He was ordered to pay a total of £9,078 in fines and costs based on his means as disclosed to the court. The court heard that other clean up, equipment purchases and compensation to the landowner, already paid by Mr Mitchell, have totalled over £35,000.

River hit hard by run-off sediment

On 7 September 2022, an Environment Agency officer identified a sediment pollution to the Back Stream watercourse in Combe Florey. A considerable length of the bed of the watercourse was found to be covered, bank to bank, in a thick layer of sediment. The investigating officer traced the pollution to a large field close to the railway bridge in Combe Florey where soil had run off the field down onto the A358 and into the Back Stream.

The field had been rented that year by Mitchell to grow potatoes, which had not yet been harvested when the pollution occurred. Thunderstorms and wet weather conditions resulted in the loss of an estimated 50-100 tonnes of soil from the field.

Large numbers of potatoes could be seen in the watercourse and along the edge of the roadside, along with the significant quantities of silt and mud. The busy A358 had to be closed on two occasions for the Highways Agency to clear drains and remove tonnes of soil from the road.

The soil deposited under the railway bridge was so deep it prevented vehicles from being able to use the A358. Mr Mitchell agreed to pay compensation of £1,128.10 to a motorist for their losses as a result of this incident.

A considerable length of the Back Stream watercourse's river bed in Combe Florey was covered, bank to bank, in a thick layer of sediment.

Road closed by similar incident month earlier

The Environment Agency investigations revealed that there had also been an earlier incident in August 2022 which had also closed the A358. Following the initial incident in August, Mitchell, an experienced potato grower, was provided with silt fencing along with guidance and advice paid for by the Somerset Rivers Authority. Only a small section of fencing was used and this was not installed according to the guidance given by advisors.

A small number of hay bales and a soil bund had also been installed at the bottom of the field in an attempt to prevent further soil from leaving the field. It was also established that the potatoes had mainly been planted up and down the sloping field which significantly increased the risk of soil erosion and run off.

Environment Agency expects all farmers to be aware of their legal responsibilities to prevent pollution events

The Environment Agency expects that all farmers need to be aware of their legal responsibilities to prevent pollution events like this from happening. Farmers renting their fields for the growing of high risk vegetables should ask prospective tenants what they intend to grow and ask to see their risk assessments and soil management plans to ensure they don’t also potentially become liable for such incidents.

David Womack, of the Environment Agency, said:

“David Mitchell had control and custody of the land he rented up until the point of harvest and was therefore responsible for the land management practices.

“He chose to grow a high-risk crop on a sloping field with light soils. As an experienced potato farmer he should have identified the risks of using this field and taken reasonable steps to prevent large scale soil loss.

“No formal risk assessment and no adequate precautions to prevent soil loss had been taken. This made it highly likely that soil erosion and environmental damage would occur in even moderate rainfall conditions.”