The successful prosecution at Leeds Crown Court on Friday 28 January 2022, was brought by the Environment Agency following a pollution incident in November 2017. Caused by the failure of a valve at Yorkshire Water’s Dale Road sewage pumping station in Cockersdale near Bradford, an estimated 20 million litres of raw sewage was discharged into Tong Beck over a four day period between the 4th and 8th November 2017.

The unpermitted discharge of raw, untreated sewage can cause serious harm to aquatic life. An investigation into the impact of the pollution by the Environment Agency found that it had caused significant damage to the ecology of the beck and led to the death of hundreds of adult and juvenile brown trout downstream of the pumping station.

Yorkshire Water’s Dale Road site used to be a sewage works but was converted into a pumping station. The station is automated and unmanned. The pumping station incorporates an underground well into which sewage flows under gravity. From the well sewage is sent by large pumps via a rising main to a local sewage works.

The Environment Agency had raised concerns following issues with the pumps at the pumping station in 2010/11 and in response Yorkshire Water had upgraded the pumping station and renewed the pumps in 2012. During the re-fit, the company installed what was intended to be a temporary isolation valve on the rising main just outside the boundary of the pumping station. The isolation valve was intended to be a temporary measure and was not installed to the same standard as permanent infrastructure, neither was it mapped by Yorkshire Water on its asset record system or scheduled for inspection.

To deal with the fact that the pumping station is not manned there is a telemetry system at the pumping station which monitors whether the pumps are working. However, there was no telemetry monitoring of the rising main. As such, the telemetry system did not notify Yorkshire Water’s monitoring station of the failure of the valve or the resulting loss of sewage from the rising main.

A spokesperson for the Environment Agency said:

All businesses, including water companies have a responsibility to ensure their activities do not present a risk of harm to people and the environment. Yorkshire Water’s failure to adequately safeguard its systems has led to significant damage to the ecology of Tong Beck, which may take many years to recover. We welcome the ruling by Magistrates in Leeds today and hope that this sends a strong message to others that the Environment Agency will hold polluters to account.

In mitigation, Yorkshire Water expressed remorse. They said they acted quickly once they became aware of the discharge. They commissioned their own sampling and analysis, monitored the watercourse over the following days, undertook a full clean-up of the site and immediate area and undertook repairs to ensure the pumping station was brought quickly back into operation.