Water company hopes to clear air over notorious sewage plant

Campaigners intensified efforts this summer in protest at the noxious smells emanating from the facility at Saltend, which was once hailed as “odour free”.

Contractors Morgan Sindall have been working on the new unit since the spring, which will be completed by the end of the month.

So far, test results have been positive, with no hydrogen sulphide – the gas which has given the plant its infamous “rotten eggs” smell – emanating from the new facility’s 28m stack.

The unit covers the sludge processing part of the site – which tends to be the smelliest – and uses Turkish pumice infused with natural bacteria in 10 large black tanks, half of which are known aptly as “peacemakers”, to treat the air.

While hopeful it will prove a success, councillors are pressing for compensation for communities which were affected this summer by the stink, which resulted from a combination of dry weather, which meant the sewage took longer to get to the plant, and was more concentrated, and the residue of the pea harvest, which is processed in Hull.

The stench led to a record 181 complaints and a petition with 2,400 names.

East Riding councillor John Dennis, who was at a meeting at County Hall, along with four representatives from Yorkshire Water this week, said: “Compensation is on Yorkshire Water’s agenda and further meetings will take place in coming weeks.”

He said a report from Yorkshire Water admitted their current odour control unit was “overloaded” in June, with an “off the scale” amount of hydrogen sulphide produced.

He said: “Yorkshire Water said it was nowhere near the levels that could cause problems for people – but it is worrying.”

He said a team of officials would be monitoring the situation closely next summer, with anyone who complained offered a pre-printed diary to record further problems. He added: “My feelings are of hope that it will work because council residents are sick and tired of it happening year after year.”

Matt Thompson, from Yorkshire Water, said while they believed the new unit would make a significant difference, they weren’t promising there was never going to be a smell.

He said: “Ever since 2000 we have had intermittent odours issues; last summer was particularly bad because of the dry warm weather, so when it was coming through the sewers it wasn’t diluted and when it came in here it upset some of the bacterial systems we have in place. It knocked it out of kilter.

“To have issues over 11 years is unacceptable; we needed to do something different which is why since March we have been investing £3.5m.”

He added: “We believe it will make a significant difference; we are not saying it will eliminate all odours around the site, that’s being honest and acknowledging that it is a waste water treatment plant and there’s always likely to be some odours.”

The bespoke system, the biggest in the region, has been designed by Odour Control Systems, for main contractor Morgan Sindall and uses tanks manufactured by Northern Plastics in Bradford.

Mayor of Hedon Ann Suggit, who lives near the site and has repeatedly raised the issue both with Yorkshire Water and East Riding Council, said she hadn’t had a complaint in the last month, which she said was unusual.

She believed Yorkshire Water was finally getting on top of the problem – but warned: “If it isn’t right by Christmas I will be on their back.”

Bugs that really are odour eaters

The plant is one of the biggest of its kind in Europe and treats 40 million gallons of waste water every day, including a complex mix of trade effluent, before discharging into the Humber.

The new system uses “wet” and “dry” methods to combat odours, using a bacteria which feeds on the substances causing the smell. “They live on the odour and they break down the odour,” said Sean Connolly of Morgan Sindall.