Congestion Charging Location Options

by Matt Lowrie

New York is the most recent city to implement congestion pricing and it's already been a success, will Auckland be the next city to do it?

Legislation to introduce time of use charging (congestion pricing) is currently making its way through parliament, with the government intending to pass it before the end of the year. It remains to be seen whether the major issues with the bill - with the government giving itself control of the design of scheme and revenue raised by it - will be addressed by the select committee. While we wait for that, Auckland Transport have released their latest work studying the impacts of a potential congestion charging scheme.

The information released essentially expands on the work done in 2020 as part of The Congestion Question, which created a concept scheme that was unanimously supported in an inquiry by Parliaments Transport and Infrastructure Committee in 2021.

The work released focuses on the location of a congestion pricing scheme and a summary of the information is covered off in this presentation. There are a lot of other elements to any future scheme that will be needed, such just what the cost is, what else is needed to support a scheme - such as changes to public transport, and what other measures are needed to mitigate any impacts of a scheme.

To help answer the location question, AT came up with a list of thirteen different options for comparison with a mix of area and/or corridor-based options. These were shortlisted to six options. They haven't come up with a final preferred option yet as are waiting for the outcome of the legislation as well as additional work on those other elements.

By comparison, these are the seven rejected options.

For each of the six options, AT have done some modelling on the impacts of the scheme. For it they just used the prices suggested in the 2020 study - which for light vehicles was up to $3.50 per trip at peak times but less at other time - but as noted above, more work would be needed to confirm the exact amounts. On questioning, AT also acknowledged that the model they use for regional level impacts here doesn't do well with active modes so for the city centre options, where better quality cycling options exist (for some trips), there could be some good uplift too.

As you can see, there are some big differences between how many are expected would need to pay a charge across each option and there's not a linear level of impact on vehicle reduction and PT demand change, for example option 1c sees a greater reduction in vehicle trips and greater increase in PT demand than 3c while charging 22,500 fewer vehicles. AT noted that this is in large part because the city centre focused schemes are more likely to impact trips that have better alternatives already.

As part of this work AT have talking to a lot of people, including even running some deliberative democracy sessions, and one of the key takeaways was the need to have good alternatives and to avoid rat-running. The modelling undertaken for these options includes looking at where traffic increases and decreases based on these schemes. This helps to understand where work might be needed to help mitigate the impacts of whatever option is chosen. They only show the results of a couple of the options though.

I think how AT choose to mitigate the impacts will be critically important. If they just put in standard traffic calming measures but there's a heap of drivers using them it still won't be a great outcome for local streets. Instead, I think it will be even more critical that they develop and properly implement Low Traffic Neighbourhoods.

Despite the diversion impacts, the modelling suggests that overall, average speeds across the regional will increase in the morning peak by nearly 4% in option. By comparison without any pricing scheme average speeds are expected to decrease by 6% as the city continues to grow. It's also interesting that there are some quite different outcomes in the afternoon peak

AT were quick to point out that while those percentages might not sound like a lot, for trips more directly impacted by the scheme the impacts could be substantial and in line with the travel time savings promised by big rural motorway projects. What they don't note was that they would achieve these savings while also generating additional revenue, something those motorway projects never do.

In a briefing AT also came up with what they labelled a 'crude' measure of efficiency for these options by looking at the average minutes saved regionwide compared to how many vehicles get charged. Based on this measure, option 1a was considered the most efficient with an average 10.8 minutes saved across the AM and PM peaks per vehicle charged followed by 1c at 10 minutes. Options 2c, 3b and 3e were all similar at around 9.3/9.4 minutes and option 3c was the worst at 8.8 minutes of saving.

As well as needing to mitigate issues like rat-running, a large part of the discussion of congestion pricing schemes has been on the impacts of it to people on lower incomes. While how specifically that might be mitigated is subject to more work, they do note that the more city centre focused schemes means have fewer impacts on low-income people.

There are a couple of big things I think AT have missed in their analysis so far, or at least in the summary.

• What are the impacts to public transport

  • Presumably many buses will also enjoy some travel time savings, though some routes may get worse as a result of traffic diversion. Either way, the impacts to all of those passengers should be considered in the analysis.

  • As the analysis gets deeper, AT will likely need to understand where that additional PT demand is coming from. Will existing PT routes have enough capacity or is additional investment required to improve services.

• What are the impacts on safety - Fewer vehicles on the road should help reduce crashes but will that be offset by faster journey times?

Personally, I think option 1c seems to strike a good balance. For only a slightly larger overall area, one that better represents the central city, there is a much bigger impact on vehicle reduction and good improvements in travel times as a result. It also avoids the risk of tying another noose around the city centre. Option 2c is also appealing for its even bigger impacts but it feels like that would be much more technically and politically challenging to implement.

There's still a lot more work to be done before we get to an actual scheme and a lot will depend on the final form of the legislation.