Plans for a congestion charge on Auckland drivers might not lower the city's pollution. File photo. Photo: RNZ / Lucy Xia
Congestion charges can lower emissions and travel times by putting cordons around the central city and spending the revenue on public transport, but proposals for Auckland could end up doing neither.
It is just after the morning rush, and GNS Science carbon specialist Jocelyn Turnbull is tracking carbon dioxide and carbon monoxide on a screen.
She is in a small room high above Auckland's Wakefield Street, where machines measure pollution levels every two seconds using air collected by a tube outside the building.
"We normally see the morning rush hour really clearly, that big peak that is mainly due to fossil fuel emissions," Turnbull said.
By comparing fresh air from Manukau Heads with samples from three central city locations, Turnbull can chart how Auckland's vehicles are heating the planet and raising levels of health-damaging substances such as nitrogen dioxide and black carbon (or soot).
But, surprisingly, plans for a congestion charge on Auckland drivers might not lower the city's pollution.
Jocelyn Turnbull of GNS Science in front of the tube carrying air from above the Auckland CBD into a monitoring station indoors. Photo: RNZ / Eloise Gibson
The Land Transport Management (Time of Use Charging) Amendment Bill has passed its first reading and a select committee is due to report back next month.
The bill would allow the government to work with councils to impose charges on motorists using busy roads at busy times, either by imposing tariffs for entering a cordoned area, or charging drivers for passing specific points on busy motorways (or a combination of the two).
But in its current form, the bill would not do much to cut emissions, says Auckland University senior planning lecturer and public transport expert Tim Welch.
While congestion charges have lowered emissions and travel times in cities such as New York and London, they did so by putting cordons around their central cities and spending the revenue gained on improving public transport.
Proposals for Auckland could end up doing neither, he said.
In the bill, central government - not the council - gets the final say on how earnings are spent, and there is no requirement to spend the money on offering better options for drivers.
"Without significantly investing in alternative modes, and then investing the revenue in frequent buses, protected bike lanes, or better train services, this isn't a congestion charge, it's just a tax on those who can't afford it," says Welch.
"The wealthy will pay and keep driving while everyone else gets stuck in worse traffic on local roads," he said.
Two of the six design options prepared for Auckland Council ahead of the law passing later this year would put tolling points on selected motorways only, rather than imposing a cordon.
"Charging drivers at specific points on motorways rather than implementing a proper cordon charge is transport policy theatre," says Welch.
"Drivers will simply rat-run through residential streets to avoid the toll, shifting congestion from highways designed to handle it onto local roads that aren't.
"When you force drivers onto longer, less efficient routes through neighbourhoods to avoid charges, you're increasing emissions, not reducing them."
Welch noted cars being driven in Auckland were also getting dirtier since subsidies ended for EVs.
A regulatory impact statement prepared for the bill confirms any climate or health benefits may be negligible.
"The scale of emission impacts is small, within the margin of error of modelling," it says.
"This confirms that charging to reduce excess congestion is unlikely to have a material impact on climate and health."
The lack of emissions benefits isn't inconsistent with the government's goals for the bill, which don't include improving climate or health.
That's a change from three years ago, when former Auckland Mayor Phil Goff promoted a congestion charge as part of Auckland's climate plan and named lowering emissions among the objectives.
Climate and health have since moved off the council's priorities for any future congestion charge.
"It was agreed with council that the goal of this was congestion reduction, and the good news is that central government agrees with that and that congestion reduction is our sole goal," said Auckland Transport programme director of infrastructure Graeme Gunthorp.
"Now that doesn't mean there won't be other byproducts and benefits, and emissions reduction is likely to be one of those and that is certainly something we are going to measure," he said.
Transport Minister Chris Bishop confirmed the goal was faster travel.
"The main objective of introducing a time of use charging scheme in Auckland is to reduce congestion, however the Congestion Question report showed it also has the potential to support an improvement in local air quality and reduce greenhouse gas emissions through a combination of reducing trips and improving the flow of traffic," Bishop said.
The Congestion Question report was produced in 2020.
It said reducing carbon emissions and air pollutants would be likely benefits of congestion pricing, partly because people would spend less time idling their engines and braking.
But transport modelling in the report found any declines in emissions would be small.
From baseline carbon dioxide emissions of about 9,229,000 kilograms a day, the various design options that were modelled were estimated to lower emissions to between 9,150,000 and about 9,218,000 kg a day, depending on the design - a drop as low as 0.1 per cent.
"Actual reductions are likely to be quite localised and depend on the nature of the traffic on a particular stretch of road and how people respond to the charge," it said.
The report also said ring-fencing any revenue for urban transport projects and services had been an important factor in reducing community resistance to congestion pricing overseas.
AT and Auckland Council want the bill changed so that some of the money has to be spent on giving drivers alternatives.
"The first draft of the legislation indicates that the money would be allocated to projects as agreed to by the transport ministry and council," said Gunthorp.
"We want it to be a little more prescriptive about providing solutions for people affected by the charge, that may be public transport services, frequency for example, or other measures."
Gunthorp said staff were yet to calculate the emissions benefits of the various project designs the council has to choose from.
To save ratepayers money, they will do the calculations after the options have been whittled down from the current six, which is likely to happen after the upcoming Auckland Council elections, and after the final law is passed, likely by the end of 2025.
"Each [proposal] will provide different benefits. It will be up to councillors to decide which of those is material enough to help them make a decision," he said.
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