CONSTRUCTION work on an important bypass is being held up by a gas bubble found beneath a disused landfill site lagoon.

The unusual problem has halted work on Colchester’s Western Bypass, in Stanway.

Investigations are now under way to find a way of safely dispersing the methane gas, which has also been giving off bad smells and upsetting residents for months.

Laura Sykes, Colchester councillor for Stanway said: “Essex County Council only managed to identify the gas because of the bad smell.

“Work on the Western Bypass was meant to start in the next month or so, certainly imminently, but this gas problem is going to hold it up.

“I don’t think we now know when the work will start. It’ll be as long as it takes to sort out this gas problem.”

The bypass will link the A12 with Warren Lane, via the Tollgate retail centre.

Mrs Sykes said: “Residents are certainly frustrated.

“The bypass needs to go forward to alleviate Stanway’s traffic problems. It seems as though the bypass has been the road to nowhere for ever.”

The road will be built by developer O and H Properties, in exchange for permission to build homes nearby. It was given planning permission in 2006, but delayed by the property slump.

Mrs Sykes’s husband, fellow councillor Colin Sykes, said he understood O and H Properties would be able to deal with the gas in the next few weeks.

He added: “It is believed the methane will be vented into the atmosphere, but if, when they try to do it, there is a bigger problem and there’s more gas than expected, then they might have to burn it off.”

A spokesman for Essex County Council confirmed it was working with the Environment Agency to deal with gas from the former Bellhouse landfill site.

Fluids which leached from the buried rubbish were treated in four aerated lagoons, he explained, adding: “The lagoons have rubber liners and are built on previously landfilled waste.

“A very small amount of landfill gas has built up under one of the liners, causing it to lift and form a pocket of gas, or bubble, within the lagoon. The lagoon has been emptied and the gas will be extracted from under the liner. The liner will then be inspected and repaired, if necessary, and the lagoon refilled.

“Monitoring and extraction pipes will remain in place to prevent the problem from recurring in the future.

“In the meantime, the remaining three lagoons are more than capable of treating the current quantities of leachate being removed from the site and there is no risk to people, property or the environment as a result.”