South West Water has been ordered to pay £89,000 in fines and costs for polluting a stream in Woodbury near Exeter. The case was brought by the Environment Agency.

A court heard how large numbers of fish died following the incident at Ham Lane Combined Sewer Overflow (CSO) in September 2014 following an illegal discharge. CSOs are allowed to discharge during storm conditions to prevent the internal flooding of properties. They are not permitted to operate during periods of dry weather.

The spill was caused by a blockage that resulted in effluent being discharged into a nearby stream over one to two days. The pollution adversely affected water quality in the stream and killed more than 150 fish.

The water company must report any fish kills that occur following a pollution incident. It failed to report this important information to the Environment Agency.

Instead, a witness alerted the Environment Agency to the seriousness of the incident after seeing South West Water staff collect and remove dead fish from below the CSO discharge pipe over several days as part of its remediation work on the stream.

The discharge occurred during a period of dry weather. The dead fish included minnows, stone loach, bullhead and eels.

Pete Ball of the Environment Agency said:

It is important water companies regularly inspect and maintain their structures and assets such as CSOs to ensure they are operating in accordance with their permit and do not cause pollution.

While South West Water responded quickly to this incident, it failed to report the extent of the environmental impact of this spill, especially the fish deaths.

Appearing before Exeter Crown Court, South West Water Ltd was fined £70,000 and ordered to pay £19,023 costs after pleading guilty to breaching its environmental permit at Ham Lane Combined Sewer Overflow (CSO), Woodbury on or around 27 September 2014.