Waltham Forest Council has been criticised by its Conservative group for the number of council-owned garages left empty.
A Freedom of Information request revealed 1,005 of the 1,527 council-owned garages are unoccupied, which could represent lost revenue of more than £672,000 a year.
Cllr Emma Best (Con, Endlebury) said two thirds of garages sitting empty was an example of “financial mismanagement” from the council.
Cabinet member Cllr Louise Mitchell, who is responsible for housing and homelessness prevention, said most of the garages would require repairs before they were safe to use.
She said the council was currently focusing resources on repairing its housing stock and that there are no plans to bring the garages back into use in the immediate future.
Cllr Best said: “This is absolutely scandalous at a time when the council is scaling back on key frontline activity.
“Not only is the council losing revenue which could be invested back into communities, but we all know that vacant and derelict garages often become a hot spot for fly-tipping, anti social behaviour and drug dealing.
“The council must urgently review and rectify this, when we look at local prices for self-storage there is clearly a market for storage base which the council are simply not exploring.”
The average weekly rental cost of garages is £14 for council tenants and £16.80 for non-council tenants, adding up to between £672,000 and £810,432 in lost revenue every year.
Cllr Mitchell said: “Many of these garages are voids which would require repair before they are safe to be used either for car parking or storage.
“We are currently undergoing a large scale improvement programme across our housing stock with improving resident safety our priority.
“Before we could begin a programme of bringing garages back into use, we would need to carefully examine any requirements arising from fire safety risk assessments and also the cost of refurbishment against the possible income to be gained.”