Boris Johnson has joined the growing protest against a 45ft-high sewer ventilation shaft being built on the Thames waterfront a mile east of Tower Bridge.

The Mayor has written to Thames Water objecting to the shaft going up in front of King Edward Memorial Park in London’s East End, campaigners were told at a protest meeting last night.

He has now given his backing to the campaign against turning the park into a construction site, joining Tower Hamlets Mayor Lurtfur Rahman, Poplar & Limehouse MP Jim Fitzpatrick and London Assembly budget chairman John Biggs.

Tower Hamlets cabinet member Alibor Choundhury told the meeting at Shadwell: “The mayor won’t accept any development on the foreshore. We’re getting an independent engineer to look at Thames Water’s proposals to study alternatives and show they’re not the only ones with experts and solutions.”

Campaigners don’t object to Thames Water’s plans to lay a 17-mile-long ‘super sewer’ from Hammersmith to Abbey Mills pumping station, to relieve London’s ageing Victorian drainage system that regularly overflows into the river.

But they are adamant that the only riverside open space between Wapping and Limehouse won’t be destroyed in the process, nor will they be left with a permanent ventilation shaft towering over their homes.

The campaign has 5,000 signatures so far to its online petition and has attracted support from celebrities including Dame Helen Mirren, Delia Smith, Anita Dobson, Lee Hurst, Steven Berkoff and Kenny Lynch.