Congealed fat caused a sewer blockage, forcing waste and water onto a busy road.
Drivers reported the flooding at the double roundabouts on Palepit Corner, Cold Norton, yesterday.
Anglian Water spokesman Emma Staples said: “We are sorry that flooding is affecting the Fambridge Road and Cold Norton Road roundabout.
“Sewage has overflowed from the manhole because of a blockage of fats, oils and greases in the sewer which should not be down there in the first place."
Engineers have completed a CCTV survey of the sewer and will be jetting it to clear any remaining fats and debris from the pipes.