They say where there's muck there's money – and council bosses in Leeds will be hoping the adage proves true when they launch an advertising trial.
The council is aiming to rake in some cash from a form of advertising that makes use of the "reverse graffiti" technique.
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The trial involves cleaning selected parts of dirty buildings, pavements or street furniture to form an advertising message.
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But the decision to go ahead with the year-long trial – due to start next month – has come under fire, with one councillor accusing the council of hypocrisy.
Coun James Monaghan (Lib, Dem Headingley), street cleaning spokesman for his group, said it was a form of graffiti advertising that had been common in Leeds since last year and the council had taken enforcement action against organisations carrying it out.
The council is working on the pilot with a company that specialises in this form of advertising. It will be allowed to place adverts in selected areas authorised by the council, which will get a share of the revenue raised.
Adverts will be placed in some of the city's busiest areas including Boar Lane, Park Row and the streets around Millennium Square.
Coun Monaghan, who fears the new policy will send out a confused message on graffiti, said: "At best this trial sends out a conflicted message, at worst it is just plain hypocrisy.
"The council's streetscene team have in the past rightly considered this form of advertising as graffiti and have taken enforcement action
against companies who do it.
"But now it seems that they've given up on this approach so they can exploit it for a quick buck.
"It seems bizarre to me that the council is trying make a virtue of the fact its pavements are dirty. Instead of using dirty streets for advertising, why don't they just clean them instead?"
Coun Richard Lewis, executive member for development, said: "At a time of unprecedented cuts to the council budgets it is our duty to explore all options for saving money and raising revenue. This will allow us to protect frontline services as much as possible.
"This trial scheme is an innovative way for the council to generate revenue and benefit from a new type of advertising. Every pound raised will be reinvested in council services."