Residents in the Middleton area had been complaining of 'smelly sewege' and huge tankers.
Cotton Valley, situated at Pineham, serves a population equivalent of 2.57 million.
A major pumping station to Cotton Valley Sewage Treatment Works is in Woodall Close, in a car park used for visitors to Ouzel Park. Residents had been complaining of 'huge tankers' making their way down the street several times a day.
A spokesperson for Anglian Water has said a blockage called the disruption.
They said: “Earlier this month our teams were notified that the sewers surrounding Cotton Valley in Milton Keynes had become blocked due to a third party disposing of rubble down the nearby manholes.
"Work to clear the sewers was undertaken under emergency road works and we used tankers to ensure customers could continue to use their facilities as normal, and to protect the environment from any sewage spills.
“This work has now finished and we would like to apologise to local residents for any disruption caused during this incident. We are continuing with investigations surrounding the incident.”
