A PUBLIC inquiry is under way into levels of permitted sewage discharge into the sea on a stretch of the North-East coast.

Thirty witnesses are expected to give evidence at the hearing into Northumbrian Water's application to vary its permitted consent over discharges from outfall pipes at Hendon, in Sunderland, and Whitburn, South Tyneside.

It follows a number of objections over the discharge levels, led by the pressure group Campaign Against Sewage in the Sea at Sunderland (Cass).

Cass and other objectors, including Seaham Environmental Association, claim discharges exceed permitted levels, despite the opening of a £70m treatment plant in Hendon.

Professor Malcolm Hooper, the Cass chairman, said excessive flows of sewage bypass the new system on too many occasions, even when there is no rainfall, leading to effluent and debris littering beaches.

"We feel very strongly that we have what is effectively a nice pint pot, but a quart of sewage is bypassing it regularly. The system can't cope and we want it sorted out," said Prof Hooper, emeritus professor of medicinal chemistry at Sunderland University.

Northumbrian Water believes the inquiry will vindicate the investment and action taken by the company to improve sewage treatment in the Wearside area.

Representatives say the extra provision it is seeking is needed only occasionally, during periods of heavy rainfall. It believes the new treatment centre is capable of coping on all but a handful of days a year.

The inquiry, overseen by inspector Rupert Grantham, is expected to last up to three weeks at the Seaburn Marriott Hotel in Sunderland.