Concerns that the multi-million pound revamp of Anglia Square poses a pollution risk to Norwich's water quality have prompted an objection from the Environment Agency.
The organisation has lodged a 'holding objection' to the proposal by Weston Homes and Columbia Threadneedle for up to 1,100 homes, plus retail and commercial space, at the shopping centre.
The agency has submitted the objection with Norwich City Council, urging the authority to reject the planning application unless the developer provides more information on how sewage from the new homes would be dealt with.
Ed Abigail, planning advisor for the Environment Agency, said: "We are raising a holding objection to the application as submitted because the applicant has not supplied adequate information to demonstrate that the risks of pollution posed to water quality can be safely managed."
Mr Abigail said the wastewater treatment site which serves Anglia Square is Whitlingham Water Recycling Centre.
He said that is at 99.9pc capacity and added: "Its ability to treat additional flows is extremely limited."
He said the developers should have discussions with Anglian Water to consider those capacity issues and to come up with solutions to treat wastewater flows.
He said: "The applicant can overcome our objection by submitting a foul water strategy demonstrating how foul water flows will be managed.
"The proposal needs to give consideration of the capacity for treatment of the additional foul flows at the Anglian Water treatment works, so not to cause deterioration of the water environment."
However, Anglian Water, which is not a statutory consultee for the planning application, believes there is still capacity at Whitlingham Water Recycling Centre.
It has scheduled meetings with the Environment Agency over the methodology the organisation used in its calculation that the centre is at 99.9pc capacity.
Weston Homes was approached for comment over the Environment Agency's holding objection but did not want to comment.
Previous proposals for Anglia Square were blocked by then local government secretary Robert Jenrick two years ago, despite a planning inspector recommending approval.
Fresh plans have dropped the controversial 20-storey tower, which proved so divisive in the initial application, but the scheme is being opposed by Historic England and SAVE Britain's Heritage.
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