It’s for carrying out unsafe street works and works under the Immediate works category when they should have been planned.
Thames Water was charged for five offences and also has to pay £10,000 towards the Council’s legal costs.
Council officers witnessed unsafe working practices at four locations between January and July last year.
Work sites contained open excavations and mechanical equipment which could have put members of the public at risk.
This prosecution brings the total amount of fines by the council against Thames Water this year to £107,000.