A SURVEY of sewers in Henley will take an additional three weeks.
Thames Water engineers had expected to spend six weeks inspecting tunnels using CCTV but the work has not been completed in time.
Nearly seven kilometres of sewers have been mapped, surveyed and cleaned so far.
Michael Cathorne, Thames Water’s project manager, said: “We have cleared four big blockages but not found any major problems.
“However, as our work moves into the town centre in the next couple of weeks, we expect to come across some of the more heavily fat-blocked pipes.
“A lot of the work that has been done has involved mapping out the new sewers which we took ownership of last October in the transfer of private sewers.
“Getting this done is a lengthy process so we are expecting our work in Henley to take another three weeks.”
The company says it is investing Ł246million to reduce the likelihood of sewer flooding by 2015.
Common causes of sewer flooding are population growth, paving over green spaces and disposal of fat, oil and grease.
For more information, call the Thames Water helpline on 0845 9200 800, quoting reference number 966800.