AN agricultural expert is warning that highly-toxic run-off from Wiltshire farms could leak into and pollute waterways this summer if farmers aren’t vigilant.

Rupert Wailes-Fairbairn, of leading farm insurance broker Lycetts, is urging farmers to check their clamps ahead of the season's first cut, which was delayed by the cold, dry spring.

If the effluent from the silage clamps gets into the waterways, it can have a devastating impact on fish, wildlife and ecosystems as it could be up to 200 times more toxic than untreated sewage.

He fears that too many farmers haven’t checked their silage clamps are airtight and leak-free because they aren’t fully aware of the dangers of poor silage storage.

“Silage effluent is extraordinarily toxic - so the damage it can cause to watercourse eco-systems is profound,” he said. “Once the effluent is in the ground and reaches a watercourse, it is very difficult to contain."

Mr Wailes-Fairbairn says the run-off can find its way into springs, wells and boreholes and public water supplies which will then require immediate action by an Environment Agency-approved contractor.

“Farmers must therefore make every effort to ensure their clamps are well maintained, and that includes all pipes and tanks as well.”

According to the Environment Agency, there has been a steady rise in the number of water pollution incidents in recent years, from fewer than 6,500 in 2015 to almost 7,600 in 2019. Most of these are caused by water/sewage companies and farmers.

If farmers are found to be negligent in their storage of silage and other polluting materials, such as agricultural fertiliser and slurry, they face hefty fines.

Mr Wailes-Fairbairn said that whilst insurance cover is available for the clean-up, it is not available for the substantial fines that could result from action taken by the Environment Agency as a result of any incident.

“Farmers have many HSE and Environment Agency standards to comply with and must keep ahead of the game to avoid these fines, which remain uninsured,” he added.

“Now is the time to do robust checks on the clamp, before the first cut of the season. Measures should include checking that the floor is sound, that cracks are properly repaired and that wall coatings and overlapping protective films are intact.

“A deep clean will allow farmers to inspect the clamp for damage, as leaks will be more easily identifiable but be careful not to damage protective lining, asphalt or concrete surfaces.

“Collection channels should be regularly cleaned out and drains checked to ensure they are watertight. Before filling the clamp, flush the drains with water to ensure they are free from leaks or blockages.

“Remember after filling the clamp to regularly monitor effluent levels and routinely check nearby watercourses for signs of pollution.

“This proactive approach will not only allow farmers to rest easy in the knowledge they are fully compliant with working practices and not polluting the environment, but that they won’t suffer an unexpected financial hit if things go wrong.”