A water supplier has admitted to polluting a Wiltshire river for many hours, which killed thousands of fish.

Wessex Water Services Limited, of Claverton Down Road in Bath, indicated pleas of guilty to three charges related to issues at Bowerhill Lodge Sewage Pumping Station near Melksham in 2018.

The body discharged stormwater into Clackers Brook between March 27 and April 3, allowed screened sewage to be discharged between July 29 and August 2 as a result of a mechanical electrical breakdown which could have been prevented, and failed to notify the Environment Agency immediately that discharges had occurred from outlet A of the pumping station between March 26 and August 21.

Wessex Water also admitted to a fourth charge which related to a separate incident at Wick St Lawrence Sewage Treatment Works on August 20, 2018, when untreated sewage effluent was discharged into the marsh rhyne system without an environmental permit.

Swindon Magistrates' Court heard earlier this month that 2,160 fish from 10 different species -  some of which were threatened and listed by conservation organisations - died as a result of the Bowerhill spill which polluted 1.1km of water for more than 54 hours.

The Wick St Lawrence spill lasted 28.5 hours and killed a number of eels from protected species.

Rebecca Vandstone, prosecuting on the Environment Agency’s behalf, said that “systemic failures” caused these incidents.

Solicitor Richard Kimblin KC, argued that their underlying causes – a hook breaking and pipe bursting, respectively – meant that his client’s culpability was “at the lower end of the spectrum”.

The defendant had entered guilty pleas at a hearing in October 2023. This latest step in proceedings was to determine whether Swindon Magistrates' Court or the Crown Court should deal with the matter.

The prosecution pushed for Wessex Water to be sentenced in crown court while Richard Kimblin KC, argued that his client should be sentenced in Magistrates court.

Ms Vandstone suggested that the utility provider’s annual turnover of £550m pushed it outside of the guidelines for penalties that the magistrates court can award, while Mr Kimblin countered by saying that it was not an exceptional case as the two events “arise from causes that are unfortunate but understandable.”

District judge Joanna Dickens said that she has dealt with cases involving very large companies in Magistrates court before and so decided this new one should be sentenced there, too, on Monday, September 30.