Hundreds of fish and thousands of shrimp were killed by the leak into the River Crouch in Essex last August, a judge heard yesterday (July 22).

The company was fined £20,000 and ordered to pay full Environment Agency’s, who warned Anglian of the leak, costs of £27,837 after pleading guilty at Basildon Crown Court.

Among the 666 fish killed were 187 eels, a protected species in danger of decline, particularly in East Anglia.

Others killed included large perch, chub and flounder as well as smaller flounder, bullheads and stone loach.

Several thousand dead young fish were also seen but were too small and numerous to count.

Mark Watson prosecuting said the pollution affected at least two kilometres of the River Crouch which flows through ‘protected environments with local, national and international conservation statuses’.

He said: “Anglian Water believed a transient fault with the electricity supply caused the pumps to fail at Long Meadow Drive Sewage Pumping Station.

“But there was no evidence as to why the system failed on this occasion. The company had not been alerted by its measuring equipment on site and only knew of the pollution when alerted by the Environment Agency.

“During investigations carried out by agency staff sewage was seen overflowing from a manhole and discharging under the nearby A132 road bridge, turning the river grey.”

Mr Watson added that Anglian’s records also showed that two alarms at the sewage pumping station failed between 8.43am and 7.48pm on the day of the pollution.

An Anglian Water manager told the Environment Agency there was a high level sensor at the Long Meadow site but it was ‘not active due to a power fluctuation’ earlier in the day.

He said pumps at the site had been replaced and required more power. He also told them that some changes had been made at the site since the pollution.

In a statement after the hearing the firm apologised: “Our investigations showed our pumping station was operating as it normally should, until an unpredictable and temporary fluctuation in the electricity supply.

“This was despite all precautions we had in place to try and prevent such an occurrence. This incident was entirely unintentional and we are sorry that it happened at all.”

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