How the government hopes air pollution will not be a block on a Heathrow 3rd runway

The Government has produced claims that adding a 3rd Heathrow runway would be compatible with air quality limits for NO2. The DfT statement on 25th October stated that the government had  done more work, since the Airports Commission, and this “confirms that a new runway at Heathrow is deliverable within air quality limits, if necessary mitigation measures are put in place, in line with the ‘National air quality plan’, published in December 2015.” That air quality plan has since been judged inadequate by the High Court ruling in the case brought by ClientEarth. The DfT also said: “Heathrow’s scheme includes plans for improved public transport links and for an ultra-low emissions zone for all airport vehicles by 2025. The government will make meeting air quality legal requirements a condition of planning approval.”Lawyers Bircham Dyson Bell comment: “would you build, or invest in, a new runway if you weren’t sure it could be used?” Heathrow and the government hope that, by 2040, 55% of Heathrow passengers will be using public transport, but there is no guarantee whatsoever that legal air quality limits would in reality be met. Currently [2012 data] about 41% of Heathrow passengers use public transport (about 28% by rail and 13% bus/coach – on the road). Heathrow hopes 43% will use rail by 2030. That is estimated to mean an extra over 56 million passengers using public transport compared to around 29 million today, and 6 million more passengers travelling to and from the airport by car.


Air Quality Judgment And Implications For Infrastructure Projects

BY ANGUS WALKER (Blog for law firm, Bircham Dyson Bell)


Today’s entry reports on this week’s High Court judgment on air quality.

The second most important legal case of the week has implications for infrastructure projects. (So does ,  [meaning the one on Brexit and Parliament] but we might as well wait for the appeal to the Supreme Court that will be heard on 7-9 December possibly by all 11 justices (there being one vacancy)).
The case is the second challenge by ClientEarth, an environmental pressure group, to the government’s air quality plans. It first challenged them in 2011, and the case went all the way to the Supreme Court, then the Court of Justice of the European Union, before being returned to the Supreme Court and .In that case the Supreme Court decided that air quality plans produced in 2011 by the government were inadequate and that revised plans had to be prepared and published by the end of that year. 
Accordingly, in December 2015, the government published for each of the UK’s 43 zones and agglomerations. You will notice that the plans deal specifically with nitrogen dioxide, as that is the toughest pollutant to keep below the required thresholds.The obligation under the is that if concentrations of certain pollutants in the air is still above set thresholds by 2010, then they must be brought within the thresholds as quickly as possible.
The two main thresholds are that average concentrations of NO2 must be below 40 micrograms per cubic metre, and that NO2 cannot be higher than 200 µg/m3 for more than 18 separate hours across a whole year.London in particular has some way to go, as that hourly threshold was breached on 9 January this year.

This week’s judgment

ClientEarth challenged the December 2015 plans again for being inadequate and on Wednesday the High Court ruled in their favour, quashing the entire suite of plans.  is pretty damning.

The main points are as follows:

The government decided against some measures to combat pollution levels on grounds of cost, but the court ruled that effectiveness of the measures should outweigh cost (albeit conceding that some measures such as banning all cars from city centres were disproportionate in their effects and therefore need not be considered). Paragraph 50 of the judgment states:

‘The determining consideration has to be the efficacy of the measure in question and not their cost. That, it seems to me, flows inevitably from the requirements in the Article to keep the exceedance period as short as possible.’

Secondly, the government’s practice of only doing modelling every five years to see how each zone is getting on was considered too infrequent in this urgent situation. Apparently they decided the EU wouldn’t start fining the UK until 2020 so that’s when they were aiming to achieve the targets, rather than the requirement of as soon as possible.
Thirdly, the model used by the government, the ‘computer programme to calculate emissions from road transport’, or COPERT, significantly underestimated air pollution compared with real-world measurements, and there was evidence that the government knew that but carried on using it regardless.The latest emission standard for vehicles, Euro 6, aims to limit NO2 emissions, and COPERT assumes that vehicles will in fact be 2.8 times over the limit. Depressingly, that is apparently too low an estimate and it should be four to five times. The judge concluded:

’86. [The air quality plans] identified measures which, if very optimistic forecasts happened to be proved right and emerging data happened to be wrong, might achieve compliance. To adopt a plan based on such assumptions was to breach both the Directive and the Regulations.’

The judge upheld ClientEarth’s case and quashed the entire suite of air quality plans. Further relief is being argued about next week.


The government is going to have to do much more to combat air quality and fork out some serious money on it if it is not to find itself in the courts again. To me, the 2015 plans just seemed to be a parroting of local authority measures without adding very much to those, so it seemed pretty inevitable that they would be shown up as not achieving the targets as quickly as possible.

The issue of Brexit hangs in the air – if and when departure from the EU happens, will the deal allow us to alter our air quality obligations? Even if so, that wouldn’t go down very well with many people, including the Mayor of London, and might well be too much of a political hot potato to do.

As most air pollution is caused by vehicles on the road, this may give rise to problems with projects that involve a lot of vehicles using the road, including highway, and of more recent interest, airport projects.

 with the proviso that it should only be allowed to operate if it could do so without slowing down compliance with air quality targets (see page 11).  [The Airports Commission’s Final Report said:  “Additional operations at an expanded Heathrow must be contingent on acceptable performance on air quality. New capacity should only be released when it is clear that air quality at sites around the airport will not delay compliance with EU limits.”]

When taking its decision to endorse Heathrow, the government commissioned further air quality work to demonstrate that Heathrow could expand without slowing down compliance.  [AIR QUALITY RE-ANALYSIS IMPACT OF NEW POLLUTION CLIMATE MAPPING PROJECTIONS AND NATIONAL AIR QUALITY PLAN   October 2016 by WSP Parsons Brinkerhof ] uses the same model, COPERT, and indeed admits in its foreword on page 1 that it doesn’t even take the latest COPERT factors into account. If that is based on a significant underestimate of emissions from vehicles, it is difficult to see how it remains valid.

[COPERT is an MS Windows software program aiming at the calculation of air pollutant emissions from road transport. The technical development of COPERT is financed by the European Environment Agency (EEA), in the framework of the activities of the European Topic Centre on Air and Climate Change. ]

Indeed, the government announcement [25th October 2016] says:

“a new runway at Heathrow is deliverable within air quality limits, if necessary mitigation measures are put in place, in line with the ‘National air quality plan’, published in December 2015.”

Well, that plan has just been quashed for inadequacy (although I note amusingly that a policy on page 228 of is ‘No third runway at Heathrow’).

The government goes on to say ‘The government will make meeting air quality legal requirements a condition of planning approval.’ That is probably unnecessary if they are legal requirements, but would you build, or invest in, a new runway if you weren’t sure it could be used?

On top of recent developments on air quality though, the  [work done by Jacobs for the Airports Commission, November 2014] on surface access states as follows (3.4.2):

‘with the baseline network in place by 2030, 43% of passengers are predicted to travel to and from Heathrow by rail, a value which is significantly higher than the 28% rail share observed in 2012. The proportion of passengers arriving at Heathrow by car is expected to reduce from 59% in 2012 to 46% in 2030. This would mean that there will be over 56 million passengers using public transport compared to around 29 million today, and 6 million more passengers travelling to and from the airport by car.’

Call me unsophisticated, but I just can’t see how adding 6 million car passengers a year onto the access routes to Heathrow won’t slow down achievement of air quality targets. But maybe I am being too simplistic and I am happy to be persuaded otherwise.Anyway, two very significant High Court judgments affecting infrastructure projects – and much more – in one week is certainly something to write home – or a blog – about.

4 November 2016



The Jacobs report for the Airports Commission also states: 

7.1.4  .(Page 74) ……. Currently,  [? 2014] 59% of passengers at Heathrow travel to the airport by car or taxi, and of the 41% who travel by public transport, 28% use rail and 13% bus/coach.  Similarly, around 43% of employees at Heathrow currently commute to the airport by car/taxi, with the 47% public transport mode share split between 35% using bus and 12% using rail.

7.1.5  The HAL submission indicated that an air passenger public transport mode share target of 52% (36% rail, 17% bus/coach) was used to test the impact of the new North West Runway on the rail network and road network. Employee mode share was assumed to be 43% public transport and 47% private vehicle.


7.2.1 Our analysis predicted that public transport mode share of passenger surface access trips to/from Heathrow would increase from 41% in 2012 to 55% in 2031. [The government document put out on 25th October says 55% by 2040.  Link ]  The main change is predicted to be in the rail mode share, which is predicted to increase from 28% in 2012 to 43% in 2031. This represents a net impact of up to 2,400 additional rail trips to the airport in the AM peak hour in 2030 as a result of the new North West Runway, with up to 1,400 additional rail trips leaving the airport.–lhr-nwr.pdf


[Jacobs (Page 86) expected around 32 – 35% of interlining (ie. international transfer) passengers by 2030. That would be about 35 million interling passengers out of about 109 million. These interling passengers do not leave the airport, give no benefit to the UK economy, but do not need to travel to or from Heathrow.

The Airports Commission Final Report  (Page 251)said:   “Without expansion, the number of international transfer passengers at Heathrow is forecast to fall from 20 million a year in 2014 to 8 million or fewer by 2050; with expansion this pattern of decline could be reversed, seeing up to 30 million international transfer passengers by 2050. ”

This Airports Commission document Strategic Fit updated forecasts (pages 137 and 138) says there would be 34.4 million international to international passengers at Heathrow in 2030 (carbon traded scenario, and 23 million in 2050.


The government statement on 25th October merely said: 

“Heathrow has pledged that there will be no increase in airport-related road traffic with expansion and committed to a target of more than half of passengers using public transport to access the airport.”   Link


Some rough calculations:

Heathrow in 2012   – 70 million passengers.

Around 20 million (about 29%) were international to international transfers.

So 50 million passengers travelled to and from the airport per year, most by road or rail (excluding domestic transfers)

41% came by public transport   ie 20.5 million (of the 50 million)
28% used rail     ie  about 14 million of the 50 million
13% used bus or coach (= road)   ie. 9.1 million  ie  6.5 million of the 50 million

59% used car    ie.  29.5 million passengers out of the 50 million


Heathrow by 2030  – about 110 million passengers

Airports Commission expects around 32 – 35% would be international to international transfers. (ie about 36 million transfer passengers).  If there was a lower proportion of these transfers, more would need to travel  to and from the airport by local road and rail.

So around 74 million passengers travelling to and from the airport each year, most by road or rail.

55% using public transport     ie. about 40 million of the 74 million
43% using rail     ie.  31.8 million of the 74 million (over twice as many as now – 17 or 18 million more than now)
12% using bus or coach (= road)   ie. about 9 million of the 74 million

45% using car    ie about 34 million passengers, of the 74 million (about 4.5 million more than now – about a 15% increase.)


Heathrow by 2040 – about 128 million passengers

AC said (Page 251) there could be 30 million international to international transfers by 2050

so about 100 million passengers travelling to and from the airport each year.
55% using public transport   ie. 55 million of the 100 million 

If  43% use rail   i.e. 43 million  (compared to 14 million now- that’s 29 million more)

If 12% use bus or coach  (= road)  ie.  12 million (compared with 6.5 million now)

45% use car    ie.  45 million passengers  (About 15 million more than now – or about 53% more than now).


But the numbers needing to use public transport, or the roads, would be much higher if Heathrow does not has as much as 32 – 35% of its passengers as international to international transfers, who do not leave the airport.  The numbers could all then be up to a third higher.

AW note

Heathrow third runway ‘can be built without a drop in air quality’

By JOE MURPHY (Evening Standard)

A minister has insisted that Heathrow’s third runway can be built without air quality getting worse in the capital.

Environment Minister Therese Coffey made the claim to MPs who lined up in the Commons to protest against London’s toxic air.

Twickenham Tory MP Tania Mathias said Heathrow expansion should be abandoned following the Government’s defeat in a court ruling this week, when judges ruled that current air quality improvement plans were not good enough.

“How can the Government support more pollution that would come from a third runway at Heathrow?” she demanded.

Tom Brake, the Liberal Democrat MP for Carshalton & Wallington called for action “now to improve the appalling air quality around Heathrow” and said the third runway should be halted “unless air pollution can be contained within the legal limits”.

But Dr Coffey insisted a third runway could be built “without it having an impact on the UK’s compliance with air quality limit values”.

She went on: “Policies at national, London and local level will help to ensure that the scheme can be delivered in line with our legal obligations in respect of air quality.”

…… and the rest of the article is not about Heathrow …. full article at