An article in the herald earlier this week highlighted some of the health issues we see have with motorways.

People who live beside Auckland’s Southern Motorway are subjected to air pollution at nearly double the level of those 130m further away, research shows.

The researchers suggest looking at preventing people from living within 20m of motorways and building more walls to separate the roadways from homes, children’s facilities and businesses.

Fixed and bicycle-mounted measuring instruments, used in autumn and winter in Otahuhu, detected pollution levels that peaked beside the motorway from 7am to 9am, coinciding with the morning commuter rush.

The researchers, from Canterbury University’s geography department and the National Institute of Water and Atmospheric Research, found similarly high levels of pollution along Princess St, which feeds the motorway, and several other areas of high traffic volume.

Potentially of most concern is their finding of a morning peak of around 140,000 “ultrafine” particles of pollution per cubic centimetre of air.

These particles, a 10,000th of a millimetre in diameter, can penetrate deep into the lungs. Particulate air pollution is associated with lung disease and heart problems.

What this really shows is one of the key issues of having such a reliance on urban motorways. It also makes me wonder what it would do to the business cases of projects if we had also considered the health impacts and the mitigation needed to address those impacts. The article says some researchers are now suggesting we need a 100m buffer to motorways, the costs of doing that would be astronomical from both a financial and land use perspective.

Some will of course point out that electric cars will solve these problems and while it may to a large extent, as Peter has pointed out in the past, uptake of electric vehicles has been glacially slow and there is no sign of that changing any time soon.

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  1. A big finding from that studies author which the TV news story about it did mention briefly, is that the “perception of health impacts” from motorway pollution is just as important as the actual impact on health of the motorway pollution.

    In this manner it mirrors the findings with regards concerns that people have over electric power pylons and cellphone towers.

    The Environment court has previously accepted (in rejecting an application for a cell phone tower in Glenn Innes many years ago) that where a perception of health risks exists with a cellphone tower being proximate, then that is just as important to those residents and neighbours as if the cell phone tower had real and proven health impacts.

    Given that you have to wonder how come projects like Waterview (even tunnelled) got the go ahead.

    And of course while zero emission cars may be coming the same doesn’t apply to trucks yet, so while the NZ car fleet could eventually go electric the same for the truck fleet is not possible, so the pollution from the transport industry will be present for a long time to come.

    Even with the latest pollution standards for trucks It will take decades for these low pollution diesel engines to wash through the fleet.
    And all such low pollution engines rely on regular maintenance and tuning to stay that way – something NZ fleet owners do not do well.

  2. Bad pollution was found in Customs Street last year attributed to buses. Are you suggesting we should have a 100m barrier for bus routes as well?

    1. Can’t do that, but putting in LRT is a good start – until proper “zero emission” buses are practical and affordable.

    2. Actually the University of Auckland scientists attributed it to traffic, then The Herald arbitrarily started talking about ‘dirty buses’.

      Just because John Roghan blamed buses for all of Aucklands pollution doesn’t make it true, it just makes Roghan a bad journalist who doesn’t like buses.

        1. You only need read the report carefully:

          What appears to be the findings of reasesrch at first glance is actually just pure speculation from the Herald.

          The comment from NIWA is that the air quality on Customs St is poor. Then The Herald immediately notes that ‘hundreds’ of buses use the street each day, and neglects to note it is used by tens of thousands of cars and trucks a day.

          Then the NIWA scientists it’s not that bad by world standards. Then the Herald finds three people to speculate that it must be due to the buses, their usual go to gang of people with an axe to grind (including a “highly reputable” tax fraud who is off to jail shortly who has crusaded against buses for years)

          Not once is there any evidence the scientists attributed the pollution levels to buses, only traffic. They also note high nitrogen dioxide levels on customs, and queen, and albert, and victoria and Wellesley, I.e. Every main road in the city they looked at. It was the herald who decided to focus on customs st and to blame buses for everything.

          Note the last comment where NIWA admitted their methods where fairly unreliable. A real journalist would have reported “air pollution at or exceeding WHO recommendations across the central city”. The herald reports “we think buses are gross and were not going to mention cars once”.

        2. Should be a comment to Nicks comment.

          I think the finger on pollution is firmly and fairly pointed at diesel engines, whether thats buses or trucks or cars.
          This comment from study indicates that:

          “On the other hand, the study found concentrations of carbon monoxide from petrol cars were “far below any relevant standards or guidelines”.”

          So petrol cars are off the hook as the cause.

          I note this article on the Telegraph in the UK from last year on the subject of Diesel powered engines:

          Basically the Euro5 diesel engine standard doesn’t actually measure real world driving behaviour and so fails to measure the actual level of NOx (Nitrogen Oxides) produced by diesel engines – the main focus of the Herald story.

          And this all mirrors the tests that governments and tobacco industry used for years to measure Tar levels in cigarettes – the government tests didn’t cross check their tests with real life behaviour so when tests show low tar fags would work, and low tar fags came in, people actually just sucked harder on the fags to get the same hit of tar – something the government tests didn’t allow for, so while the industry could truthfully say they were dealing with it, they weren’t really. And yeah Euro6 standard helps – but only if you keep using the additives to make the catalysts remove the NOx components. Something a lot of diesel drivers would fail to do I’m sure in practice rendering Euro6 engines no better for NOx emissions I’m sure.

          But, fingering a few hundred buses while ignoring all the other (diesel) traffic in the mix is a bit of typical Herald shopping around for a culprit though.

          I also note Mike Lees comment on the matter:

          “Council infrastructure chairman Mike Lee said the results showed a need to reconsider introducing electric light rail to Queen St and its surrounds rather than double-decker diesel buses favoured by planners.”

          Which gives another hint as to why AT are looking at LRT over more diesel powered buses in the CBD.

        3. Can someone listen to Mike Lee, he tends to make sense consistently. Double deckers are an answer for the Northern Express and for the further outreaches of the network but not in the Auckland CBD. They are a cutesy London sort thing but they are a going to require more horse power and hence more emissions and it’s already revolting being a pedestrian around buses,trucks and lighter vehicles.

        4. +1

          Most of the really filthy buses are gone or going, but they could be more proscriptive with the latest standards for new buses.

          While I don’t accept that buses are the only thing causing pollution downtown, as argued above, they obviously do contribute. Given very clean vehicles are out there and on the market Auckland should be demanding them.

    1. Its not just motorways, its also building/turning arterials into de-facto urban motorways, like Te Horata Road, Pakuranga Highway as well.

      And while we can blame NZTA for the omtorways, AT is the agency responsible for those urban examples.

    2. Ain’t that the truth and yet ironically Wellington are getting rid of trolley buses. Diesel buses are quite good with emissions when new (the bus companies love to emphasise Euro 3 etc standards) but they go down hill spectacularly the higher they get in mileage and of course the standard servicing they receive. And diesel, worse than petrol, emits some deadly gases and equally deadly soot.

    3. Cruise Ship pollution?
      Not overly relevant in an Auckland city context. As the report itself says on air pollution:

      “The smokestack and exhaust emissions produced in one day by a single cruise ship have been estimated to be equivalent to those produced by 12,000 automobiles”

      So a cruise ship cruising around (not just docked) in Auckland harbour for an entire day equates to much less than 2 hours worth of pollution from all the cars and light trucks that cross Auckland Harbour Bridge?

      And note, when a cruise ship is docked e.g. for a day visit, the main engines don’t run – just the generators, producing much lower levels of pollution.

      I think we have bigger fish to fry. Like all those vehicles on the motorways all day and everyday and all the vehicles that use Customs Street for examples.

      And maybe at the outside all those container ships that come and go day in day out, they’ll cause more pollution than the cruise ships do.

        this ship visits the port few times a year, initially i thought it was having an engine problem, but it actually smoked like that for all the day it spent at the port and then she left. You can imagine the soot and the smell.

  3. I remember the black bogeys everyone used to get from the tube when I lived in London. Surely that can’t be healthy either?

  4. The motorway at Otahuhu is between 6 and 8 lanes depending on just where this is measured. I would hate to think what it would be at Western Springs or Grey Lynn where its 8 to 10 lanes when fully completed (this time around that is)

  5. Similar results come from studies of intersections with traffic lights, which have substantially greater negative health effects than grade separated junctions and roundabouts. The more the traffic stops and idles, the worse the air pollution. That’s why the idea of replacing the free-flow Dominion Rd flyover with congestion-causing traffic lights, then somehow regarding the created pollution hotspot as being a good place to put people, is poorly thought out.

    Road vehicles kill more people with their exhaust than they do in crashes, and intentionally putting yourself into that environment on a regular basis, such as living there, is akin to not wearing a seatbelt.

    1. But Geoff that’s fiddling about In the decimal points compared with investing to achieve real shift to transit and active modes from private car use. One car journey not taken will make far greater difference to total and local emissions than a few seconds of idling saved at one intersection.

      1. It won’t make any difference to the people living beside the newly created intersection (in a bubble of air pollution that probably exceeds WHO standards) whether they own a car or not Patrick. They’ll be slowly poisoned regardless.

    2. I think history shows that the more you “free up” traffic from impediments such as traffic lights and intersection idle-points, the more traffic you encourage in absolute terms. And over time, the more you do this, the more you detract from other, cleaner modes.
      Conversely, if you intentionally impede traffic, take away traffic capacity etc, then traffic is deterred. Initially it may shift elsewhere and congest other routes, but ultimately it will disappear as people re-order their behaviour patterns based on the opportunities actually available. If traffic-impedance is applied together with appropriate public transit improvement, then very quickly traffic volumes can be made to scale down, both at the impedance-points and overall. The polar-opposite of traffic inducement through “freeing it up”.

  6. I’m a sensitive petal and easily affected by chemicals which can make me physically sick. Renting in Arch Hill for six months was a particularly bad experience. From about 6.30am the emissions from the motorway would have me choking. While I’m easily affected my partner isn’t but it demonstrates that everybody in that area must be ingesting particles that are not good for your health.

    1. The NZTA routinely monitor air quality at some key locations, including Arch Hill. See Site AUC022 is in Arch Hill near the North-Western. It has been reporting what NZTA calls ‘medium’ concentrations of nitrogen dioxide since 2007, but levels appear to be rising. I understand an update to this report with more recent data is due for release soon. However the levels are higher than those found by the Otahuhu study reported in the Herald, and to put the label ‘medium’ in context, they use medium to mean less than 40 micrograms per cubic metre which is both the WHO guideline and the proposed Auckland standard (under the Unitary Plan).

      Monitoring was also undertaken around the St Lukes Interchange as part of the NoR/AEE process, but it doesn’t appear on the NZTA website. From memory I think the levels were similar.

  7. Scania buses rescently introduced in Auckland would have to comply with tough new EU emission standards..

    “Scania’s Euro 6 engines make it possible for keen operators to take the next step and invest in the greenest technology available in the market.”

    “Emissions of nitrogen oxides and particulates are cut by around 80 percent compared with the standards currently in force (Euro 5)”

  8. “People who live beside Auckland’s Southern Motorway are subjected to air pollution at nearly double the level of those 130m further away, research shows.”

    Are these pollution levels above international health standards?

    This stat tells us nothing. For instance the respective pollution levels could be 0.02 and 0.01 parts per million but if the internation standard is 0.7 parts per million it’s not really a factor is it. So how do motorway pollution levels in Auckland stack up against international health standards?

    1. There is no known minimum safe exposure to air pollutants from traffic emissions, a fact recognised in documents from AC, MfE, WHO, USEPA, etc. Our National Environmental Standards for Air Quality provide a “set level of protection”, not total protection. According to the current state of scientific evidence twice the concentration = twice the risk.

    2. “Auckland Regional Council’s monitoring has identified concentrations of pollutants (such as nitrogen dioxide (NO2) and fine particles (PM10) at urban monitoring sites around Auckland that exceeded both the National Environmental Standards and Ambient Air Quality Guidelines.”

      “The regional council calculated that approximately 80 percent of nitrogen dioxide in Auckland’s air comes from transport and that concentrations increased in the decade to 2006 due to an increase in motor vehicles on the roads.

      “Researchers estimate that vehicle-related air pollution results in 253 deaths per year in the Auckland region.”

  9. Dr Pattinson said noise walls helped “to deflect the plume of pollution”.

    Then why do we not line our motorways with suitable noise walls NZTA ?
    Not enough money ? I guess the health service will in part be paying a price for it in the decades to come until we are emission free.

    1. Because when they did that down near Manurewa a few years back, the residents across the motorway suddenly got all the sound reflected over to them – when they didn’t before and they got upset and complained to NZTA. NZTA scratched their head (and no doubt other parts of their anatomy), and said “thats not supposed to happen ,the barriers are supposed to absorb the sound and make it less not make it worse”.
      We don’t think this is possible.

      So after back and forth, NZTA then spent a boat load of money on sound and acoustic consultants and stuff and ended up deciding to redo all the barriers and change the angle of the barriers so that the sound that got bounced off them went up into the sky instead of across the motorway.

      Kind of obvious that sound barriers just move the problem don’t make it go away -but took a lot of work for NZTA to get it mostly right.

      So I think their attitude now is “we don’t do sound barriers by motorways” as they’re “too hard”.

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