On 8 September 2021, at Sheffield Magistrates Court before District Judge Redhouse, the company was fined a total of £150,000 and ordered to pay £36,506.25 costs.
Yorkshire Water Service Limited pleaded guilty to 2 charges at an earlier hearing. The charges were causing sewage sludge to enter a tributary of the Mother Drain and breach of permit condition relating to ammoniacal nitrogen levels in their final treated sewage effluent.
Representing the Environment Agency, Rebecca Chalkley told the court that Yorkshire Water Service Limited holds an environmental permit. The permit authorises water discharges from Balby Sewage Treatment Works under a number of strict conditions.
On March 28 2017, Yorkshire Wildlife Trust reported that Mother Drain at the Potter Carr Nature Reserve, had become discoloured and smelt of chemicals. The site is of Special Scientific Interest.
Environment Agency officials attended and confirmed pollution of the Mother Drain. They saw small pieces of toilet paper floating in the water, which looked grey, and sample results confirmed high levels of ammoniacal nitrogen in the water.
Due to the severity of the pollution the Environment Agency requested the Internal Drainage Board to switch off a pump station used for land drainage. It was switched off to prevent polluted water passing downstream to the River Torne, they also instructed abstractors to cease abstracting water. This included Doncaster Golf Club.
Once the Environment Agency contacted Yorkshire Water Services Limited, they confirmed that there was an issue at Balby Sewage Treatment Works.
Officers attended Balby Sewage Treatment Works on March 29 2017 and took a sample of treated sewage effluent which contained ammoniacal nitrogen above the permitted maximum limit.
During the site visit Yorkshire Water Services Limited explained that a valve failure had led to a settlement tank on site draining sewage sludge. The sludge drained inside a building and onto surrounding ground.
Later, in an interview under caution, Yorkshire Water Services Limited explained that the valve failure happened on Monday 27 March 2017. But they did not contact the Environment Agency because they thought effluent was contained on site.
The company further added that electrical damage caused by the incident affected parts of the works and disrupted the biological treatment processes. This resulted in a deterioration of the treated sewage effluent quality.
In response to the incident Yorkshire Water Services Limited placed aeration equipment in the Mother Drain. The Environment Agency continued to investigate and monitor the effects of the pollution for over a week. There was no sign of dead or distressed fish.
In court, District Judge Redhouse found the culpability of Yorkshire Water Services Limited to be ‘high negligent’. Due to the fact the incident could have been avoided if there had been a drain survey at the site and if the valves had been checked.
She stated that whilst the general public may consider the actions reckless when applying common everyday language, in criminal legal terms it was negligent. She described it as “very negligent”.
A spokesperson for the Environment Agency said:
Water companies are aware that their activities have the potential for serious environmental impacts, and they know that we will take action when they cause pollution.
In this case Yorkshire Water has failed the environment, customers and the system of environmental laws the public puts its trust in.
Polluters must pay, the Environment Agency will continue to do everything in its power to ensure that they do.
If anyone has environmental concerns they should call our 24/7 hotline on 0800-80-70-60.
On or before 27 March 2017, at Balby Sewage Treatment Works, Yorkshire Water Services Limited did cause a water discharge activity in that sewage sludge entered a tributary of Mother Drain contrary to Regulation 12(1) and 38(1)(a) of the Environmental Permitting (England & Wales) Regulations 2016.
On 29 March 2017 at Balby Sewage Treatment Works, Yorkshire Water Services Limited did breach condition 11 of environmental permit T/83/45405/R in that treated sewage effluent readings of ammoniacal nitrogen readings exceeded the maximum amount of 20mg/l of authorised by the said permit, contrary to Regulation 38(2) of the Environmental Permitting (England & Wales) Regulations 2016.