The Environment Agency has prosecuted Portsmouth Water Ltd for causing pollution to enter a tributary of the River Itchen, killing 287 fish.

The case went to court on Monday 7 January at Lyndhurst Magistrates Court. Portsmouth Water was fined £10,000 and ordered to pay costs of £1,483.

A river keeper at Lower Itchen fishery reported the pollution to the Environment Agency on 12 January 2007, when he noticed a milky white substance had been discharged into a watercourse that drains into the river. The pollutant was Polyaluminium chloride (PAC), a compound used to treat drinking water for public supply. PAC is known to be hazardous to aquatic life. The Environment Agency attended the incident immediately and found dead fish that included dace, roach, stickleback, minnows and stone loach.

Portsmouth Water Ltd helped to the clean up the watercourse.

Bill Scott, Environment Officer said: “The River Itchen is a high quality chalk stream of international importance. Portsmouth Water should be taking all reasonable steps to ensure that they do not cause pollution and, on this occasion, pumping waste water into the wrong drain has caused the death of hundreds of fish. This could have been avoided with better working practices.
 
“Fortunately, the effect of the incident was limited to this small watercourse and the nearby fishery was not impacted. This is, no doubt, due to the keeper noticing the incident and alerting us so quickly. Without his quick-thinking there was a very real prospect of the pumping continuing until the Itchen itself became polluted. We hope the improvements that Portsmouth Water have made to their operations will avoid an incident like this happening again.”