The operator of a Dorset watercress farm was today ordered to pay £5,967 in fines and costs for polluting the River Nadder with silt during maintenance work. The case was brought by the Environment Agency.
Ludwell watercress beds are located in a valley near Shaftesbury where spring water from the River Nadder flows across the watercress beds and into a lagoon where suspended solids settle out. The water is then returned to the River Nadder via a weir.
The site is owned and operated by Sun Salads Limited from Selsey, Chichester, West Sussex. The company, which runs a total of four watercress farms, holds two authorisations for the Ludwell site – an abstraction licence for taking water from the river and discharge consent for releasing settled effluent back to the river. Both are regulated by the Environment Agency.
Effluent from the watercress beds can be polluting to rivers and streams as it can contain highs levels of suspended solids and zinc. Growers use zinc to prevent a disease called ‘crookroot’, but must ensure levels do not exceed permitted limits as it can be toxic to aquatic life.
Suspended solids or sediment is found naturally in rivers but is polluting when introduced in large quantities and can damage aquatic ecosystems and affect fish breeding and health.
Every couple of years the settlement lagoon needs to be de-silted to remove any material that has accumulated. On April 3, 2007 contractors started emptying the lagoon at Ludwell before blocking off the consented discharge point to the River Nadder. This resulted in effluent containing high levels of suspended solids escaping into the river.
An Agency officer carrying out routine water sampling witnessed the spill and sampled the ‘extremely dark’ discharge to the river. The suspended solids were almost 10 times (191 mg/l) above the consented maximum of 20 mg per litre. An excavator was ‘disturbing large amounts of solids’ with each scoop.
After stopping the original discharge, contractors started pumping water through two mobile settlement tanks and into the river, but the speed of pumping was too fast and the system proved ineffective at removing suspended solids. This resulted in a second illegal discharge.
‘Prosecutions like this send a message to all those holding consents to discharge to the environment of the importance of making sure all releases meet the required standard and don’t cause pollution. This incident may have been avoided if somebody from Sun Salads had been on site to oversee the de-silting of the lagoon and ensured that no polluted water was released into the River Nadder,’ said Emily Pitts for the Environment Agency.
Sun Salads of Park Farm, Chichester Road, Selsey, Chichester, West Sussex was, today, fined £5,000 and ordered to pay £967 costs by West Dorset Magistrates sitting in Weymouth after pleading guilty to breaching three conditions of its Consent to Discharge at Ludwell Water Cress Beds on April 3, 2007 in contravention of Section 85(6) of the Water Resources Act 1991.
