The government has committed another £50million for a new Cambridge sewage works.
This means the total government funding so far has increased from £227million to £277million, breaching the funding cap originally set.
The existing Cambridge Waste Water Treatment Plant, on the north east of the city, is proposed to be replaced by a new plant on land north between Horningsea and Fen Ditton, known as Honey Hill.
The relocation project is being pursued so that the land the existing sewage works sits on can be redeveloped into 8,000 new homes.