WALTHAM Forest Council wrongly withheld information that could prove a housing association faces a multi-million pound loss on a housing development at Walthamstow Stadium, a public body has ruled.
The authority has repeatedly refused to release a viability assessment which campaigners claim will show property developer London & Quadrant (L&Q) has made a £26 million loss on the stadium in Chingford Road, Walthamstow, after buying it in the property boom to turn it into a housing estate.
The council has cited commercial sensitivity as the reason for not disclosing the documents, but campaigners insist evidence of the apparent loss is in the public interest because L&Q would be forced to tap into its taxpayer-funded reserves.
The Information Commissioner's Office (ICO) has now ordered the council to release the data after saying it would not harm any "economic interests" after campaign group Save Our Stow's (SOS) referred the refusal to the body last month.
The ICO report said: "The council has failed to demonstrate that the withheld information engages the exceptions relating to the course of justice and the confidentiality of commercial ... information.
"The commissioner does not consider that it has been shown that disclosure of the information would adversely affect the economic interests of L&Q."
SOS campaigner Ricky Holloway said: "It's the biggest victory that we've had during the whole four-year campaign.
"They have shown what the council was doing was wrong, and that it's in the public interest to show whether this is a huge loss of taxpayers' money.
"This could be one of the biggest wastes of taxpayers' money in history. We look forward with great interest to receiving the viability assessment."
L&Q hopes to build a 294-home housing estate on the former dog track but has met opposition from groups which either do not want to see the blocks of flats built or support a rival bid which includes a greyhound racing track.
L&Q's proposals were passed by the authority earlier this year but still await a date for Mayor of London Boris Johnson to approve them.
Mr Johnson has stated that the viability of the development would be a major factor in his decision.
Chingford MP Iain Duncan Smith said he hoped the mayor would take the figures into account when they are released.
“I welcome this decision as it is important for my constituents to know what the viability assessment amounted to, as well as what assumptions L&Q made to arrive at it," he added.
"I cannot understand what they had to hide and urge them to release the assessment this week and not drag it out to delay the publication.”
The council must now provide the viability figures within 35 days, or can lodge an appeal.
An L&Q spokesman said: “We maintain that this viability assessment is commercially sensitive. It is a normal part of the planning process for developers to submit commercial information to planning authorities, which both parties acknowledge may be of a confidential or sensitive nature.
“As a not-for-profit housing association, L&Q makes long-term investments to generate a surplus that is re-invested in new and existing affordable homes, and services for the people who live in them.
“Our plans will deliver a £50m iconic development which preserves the heritage of the Walthamstow Stadium site and provides around 300 new homes, a modern sports centre run by the community for the community, a children’s nursery and allotments, as well as more than 250 jobs to meet the needs of local people.”
The Guardian has approached the council for comment.