A blaze at Yorkshire Water’s waste water treatment plant at Saltend, near Hedon, destroyed an odour control unit last month, placing the burden on a new £3.5m unit installed at the site in December 2011 following scores of complaints from residents.
The company has diverted odours from the damaged unit into the new one and has also deployed two mobile odour control units, although it has now admitted some smells have escaped.
A spokesman said: “Prior to Tuesday July 16, certain parts of the site were not fully odour controlled, and consequently, given the very warm weather conditions, there have been occasions when we’ve detected an increase in odours, which we’d like to apologise for.
“We continue to operate odour masking sprays around the site when appropriate, and a regular programme of ferric dosing is further helping us to control any odours around the plant.”
He added: “Whilst there is always likely to be some odour owing to the operational nature of the site – it’s one of Europe’s biggest waste water facilities which treats up to 40 million gallons of waste water every day, including a complex mix of trade effluent – we’ll continue to work hard to manage and reduce any odours as much as possible.”
After the fire, the company was warned there would be “severe consequences for residents” if it failed to control odours at the site.
Firefighters spent an hour tackling the blaze, and local politicians feared it may lead to the release of unpleasant smells that blighted the lives of many residents two years ago.
Coun Mike Bryan, East Riding Council member for South West Holderness, said he was “bitterly disappointed” to learn of the fire but had been assured measures were being put in place to ensure smells did not escape.