After almost 20 years of the Lei Cidade Limpa (Clean City Law), which heavily regulates outdoor advertising, São Paulo is poised to backslide to its old ways. The (perhaps ironically named) Commission to Protect the Urban Landscape has approved the Boulevard São João project – a plan to cover four buildings at the intersection of Avenidas São João and Ipiranga with LED panels, in the manner of New York’s Times Square. The prospect of garish ads among the city’s historic buildings makes me anxious.

When São Paulo introduced the Lei Cidade Limpa in 2007, our relationship with our surroundings changed almost overnight. More tasteful, subtler spots were found for ads (on newsstands, for example) and we started to notice the architecture around us. Colourful murals popped up on tower blocks and we discovered major talents such as street artists Gustavo and Otavio Pandolfo, better known as Osgemeos.

From Buenos Aires to Seoul, other cities took note. Over the years, polls have shown that the majority of São Paulo’s residents approve of the law. An elevated view of the Viaduto Nove de Julho and Rua Formosa, with buildings featuring murals, including one by artist Eduardo Kobra (Image: Alamy) If the new plans go ahead, São Paulo’s buildings will once again be reduced to a canvas for ad campaigns, bombarding pedestrians with slogans – hardly conducive to a high quality of life.

When advertising is allowed to overshadow a city’s essence and character, the results are invariably ugly and confusing. The Boulevard São João project is a hard sell. For the sake of his city, São Paulo’s mayor, Ricardo Nunes, should turn out its lights. Read next:‘If you have the privilege, this is a way to survive.’ How two 1950s towers built community in São Paulo Why Casa Santa Luzia is São Paulo’s most beloved supermarket