Hundreds of protesters took to Clissold Park on Friday afternoon to demonstrate against proposed road closures in Stoke Newington.
Hackney Council wants to shut Brighton Road, Walford Road and Nevill Road to rat-run traffic to clean up the toxic air and reduce the dangerous driving that blights the residential streets around Cycle Superhighway 1 (CS1) in N16.
But that plan, unveiled in 2017, ignited a furious PR campaign from parents at William Patten Primary School in Church Street that has now spread to four other schools - Grasmere, Shacklewell, Newington Green and St Mary's.
Modelling work commissioned by the council shows traffic and pollution increasing on main roads around the scheme, but health chiefs believe this would be all but entirely mitigated by a greener bus fleet that is already being rolled out, green walls around schools, the introduction of "school street" rush hour traffic bans, and the rollout in 2021 of Sadiq Khan's ultra-low emission zone across the borough.
Working under the banner of "CleanAir4Schools", parents from the primary schools in question have argued the council should abandon the scheme until the ULEZ is introduced - something that has in turn angered families living within the affected area, who say they are already living with unacceptable levels of air pollution around the clock and that the council needs to hurry up and shut their streets to cars.
Sure enough, Friday's protest followed a counter-demonstration in Brighton Road on Tuesday urging the council to enforce the road closures as soon as possible.
It is a bitter row and neither side has shown any side of backing down.
Banners and placards in Clissold Park on Friday afternoon read: "NO2 to stunted lungs," "You wouldn't make us drink dirty water," and: "More school pollution? You must be choking."
Jenna Fansa, mother of two children at William Patten Primary school, said: "The council is ignorantly carrying on with these road closures without thinking of the consequences."
She added: "This protest is not the end. We'll take the council to court and go all the way if we have to."
The council commissioned a 12-month air quality modelling project by a team of independent experts from Cambridge University, whose results the campaigners have dismissed, and has just announced a second consultation on the project.
The team behind Friday's protest includes a lawyer, traffic expert and environmental scientist.
A parent from Grasmere Primary School, Tom Edge, was worried about the impact of the plans on his youngest child who has cystic fibrosis, a condition mainly affecting the lungs.
He said: "There's an enormous depth of feeling about these closures.
"Children will be compromised and grow up bearing the brunt of the extra pollution.
"The damage is irreversible and it's a terrible legacy to bequeath them.
"In a period where air pollution is going down overall, children are being asked to make all the sacrifices.
"Children should be going into adulthood with their best chances intact rather than have their health crippled as a result of decisions taken by other people."
The Cambridge experts' model shows that, while there would be a small increase in nitrogen dioxide pollution at some school playgrounds, all except Grasmere would still fall within the national limit of 40 microgrammes per cubic metre.
The area at Grasmere that exceeds the limit is currently a car park, the council says, but would have levels of 40.9 or 40.1, depending on which road closure option is chosen, when converted to a playground. Even this is disputed, with the headteacher saying it is merely next to a car park, although it seems to be a rare point of agreement that the car park will at some stage be removed.
Curiously, that will be done with the help of Take That star Mark Owen, who is linked to the school through Take That songwriter and parent Jamie Norton, and has recorded a charity single that will help fund both St Joseph's Hospice and the school itself.
As well as the grown-ups, child protestors were heard too.
Eight-year-old Ashveer Singh of Grasmere Primary School said: "I'm asthmatic and I'm worried these plans will make it worse and worse.
"Every day of every year people are affected. If we don't put a stop to this we might die out."
Campaigner Lucy Harbor claimed the council's actions had led to a rupturing of community spirit between rival demonstrators in the area.
She said: "It's sad that residents are pitted against one another and it's upsetting when residents badmouth us.
"We want a balanced picture with clear facts and information so that both sides can come together."
These strained relations were evident on Tuesday when families living near Brighton Road said their support of the closures was being drowned out by their noisy neighbours.
Anna Williams said: "We don't want the council to 'press pause' [a slogan adopted by CleanAir4Schools] - that will only stop progress on all of the changes the borough needs like improved cycling and reduced car use.
"If it's paused we're worried we'll disappear off the agenda and be left to live in these unsustainable conditions on our streets.
"It's only a matter of time before there's a fatal accident from all the traffic and dangerous driving."
Fellow neighbour Jonny Fort added: "For two years residents have been promised action from Hackney Council.
"There can be no more pauses, no more endless consultations.
"Local parents can't wait any longer."
Earlier this month Hackney Council shot down claims by CleanAir4Schools that air quality tests conducted by climate experts around Stoke Newington schools were "not fit for purpose".
The council is due to hold a public survey on the plans, providing it is passed by cabinet later this month.
Announcing the latest twist in the saga last week, deputy mayor and transport boss Cllr Feryal Demirci said: "The Walford Road proposals are aimed at reducing rat-running traffic and creating a better environment for walking and cycling.
"Residents of Walford Road, Brighton Road and Nevill Road in particular have raised significant concerns about the traffic and the wider adverse implications that this has for the neighbourhood.
"Residents have told us they want to look at and feed back on the proposals in light of the air quality modelling, so I'm recommending further consultation is carried out on option B of the scheme, which, is currently considered to be the better of the two options.
"This will ensure all residents can weigh up the benefits of the proposals alongside the air quality modelling and measures we're implementing to tackle poor air quality in Stoke Newington."
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