Biodiversity and climate change in North London

By Dennis Ayling, June 2022

This is about a missed opportunity in North London that has repercussions for Inner London boroughs, too.

Everyone now knows we are facing two interlinked emergencies: a devastating decline in biodiversity and catastrophic climate change.

Both threaten our survival, yet both were predicted over 40 years ago. Both are now crises over which we are imminently losing control.

In 1962, Rachel Carson's Silent Spring was published (1).

In 1979, a US National Academy of Sciences report (the "Charney report") found it highly credible that doubling CO2 will bring about 1.5–4.5 °C of global warming (2).  

This spring, the IPCC released the third part of its Sixth Assessment Report (3), looking at ways to limit & prevent human-caused emissions that contribute to global warming. “It’s now or never, if we want to limit warming to 1.5 °C." – IPCC Working Group III Co-Chair Jim Skea 

Why then, one wonders, is the London Borough of Barnet making its biggest mistake of the century in the face of the climate and ecological crisis?
Barnet is failing, at a pivotal moment in history, while all around the world others are producing imaginative and successful solutions to meet current global environmental challenges. The crying shame is that Barnet, with a little more courage, could be an enlightened civic leader for London, the UK and even internationally.

This is not a time to mince words. Let me set the context for my emphatic assertion, and then you should judge whether or not Barnet is passing up the chance to be a world leader in the face of the ecological and climate crisis.

I grew up in Barnet and I spent most of my adult life teaching in schools in the Borough. I have lived and taught in the southern end of Barnet, and I raised my own children and taught in the very green, northern tip of Barnet. I have had a lifelong love for this beautiful part of London. It is this passion for Barnet that compels me to readdress an issue I first raised over 40 years ago. At that time, I was living in Southbourne Crescent. My lodgings there were sandwiched between the rumbling Great North Road and the roaring North Circular Road. However, the rear gardens at Southbourne Crescent backed onto the Dollis Brook, close to where it gives rise to the Mutton Brook and the River Brent.

Let me start with the Dollis Brook, which already shows what is possible, and then go much wider. At Southbourne Crescent, I quickly found that I could walk north from our back garden alongside the Dollis Brook right out to the Totteridge Valley. It was an enjoyable discovery especially as it supported some significant wildlife. As a biologist and a member of the Herts and Middlesex Trust for Nature Conservation I was excited by the potential of this natural corridor. I saw kingfishers at the southernmost end of the Brook and identified aquatic indicator species in the stream that testified to its health. I began to consider how the Dollis Brook might be managed to enhance its wildlife. At the time, most of its length was a mown grass monoculture. Additionally, selective weed killer was being sprayed to maintain the brookside lawn-like appearance. I wrote to the parks superintendent suggesting that at least some areas should be managed like a hayfield to allow a proliferation of wild plants. This in turn would support a greater insect population, bird species, etc. I also advised ending the weed killer spraying because of runoff into the stream and consequent damage to the aquatic ecology. My suggestion to manage the Dollis Brook as an urban wildlife corridor was not taken seriously by the parks department. I tried writing to the local press. I recall at least one of my letters was published but nothing came of that either. However, after many decades, the Dollis Brook is now managed to support wildlife and provides a vital outdoor urban green footpath. So far so good, but what of the massive error on Banet's part?

Indulge me a little longer and I will show how the Dollis Brook, though important, was one element of a wider more profound ecological proposal. After my discovery of the Dollis Brook I started to look at the ecology of the borough more holistically. The north end of the Borough of Barnet is wonderfully green and rich in flora and fauna. Would it be possible to ecologically improve the southern end of Barnet by restoring some of its former green spaces? I have already mentioned that the Dollis Brook bifurcates near Southbourne Crescent. From there, it continues as the Mutton Brook running east and the River Brent flowing west. Both run parallel to the mighty North Circular Road but in opposite directions. At first sight, neither are at all promising as potential wildlife habitats and green footpaths.

Nevertheless, let us take a brief look at the east-flowing Mutton Brook. It immediately ducks south under the North Circular Road running towards Henley's Corner. In the 1970s, this area, too, was mown flat right up to the extremely busy roadside. I suggested planting a strip of woodland on the southern flank of the road to enhance it ecologically and to mitigate the impact of traffic noise and pollution on the green footpath to Henley's Corner. At this point, the Mutton Brook passes beneath Finchley Road. From there, it is a relatively short hop to the extensive Hampstead Heath via Little Wood and Big Wood. A wonderful wildlife corridor and green pathway from the Totteridge countryside to South End Green and Gospel Oak.

Now we can begin to focus on Barnet Council's massive missed opportunity to address the climate and ecological crisis that is now rapidly bearing down on us. Sadly, Barnet has discarded a wonderful chance to green the southern end of its borough and to meet the UN's call to make both local and global transformative change (4). Not only could Barnet have addressed enhancing the ecological diversity of the whole of its urban borough, but it could have made a significant contribution to mitigating the local impact of climate change.

For a moment, consider the current state of the short length of the River Brent that flows within Barnet's boundary.
hand-drawn map of the River Brent near Brent Cross shopping centre
As already mentioned, the Dollis Brook gives rise to the River Brent behind the rear gardens of Southbourne Crescent. The River Brent starts off reasonably well, flowing west through Brent Park, a narrow green wooded strip parallel to the North Circular Road's northern edge. It then passes under Brent Street (A502) to continue between the gardens of houses bordering the North Circular Road and Shirehall Park. This green stretch has wildlife potential, too. However, the next section where the river flows under Brent Cross Flyover and along the southside of Brent Cross shopping Centre to the Brent Reservoir (Welsh Harp) is an utter disaster and has been since I first raised the matter in the late 1970s.

I have already mentioned my early campaign to promote a Dollis Brook wildlife corridor and my efforts to champion it by approaching Barnet Borough's Parks Department and writing to the local press. However, linking Barnet's rural north to Hampstead Heath by enhancing the Dollis Brook and Mutton Brook was only half of my proposal for increasing the biodiversity of Barnet. The other half of my Borough-wide scheme was to have a west wildlife corridor from the Dollis Brook to connect with Brent Reservoir via the River Brent. Clearly, the west branch requires greater effort to refashion it as a wildlife corridor, but it is not impossible. What is more, it would hugely enhance the traffic-blighted southern end of the Borough.

I know for a fact that the full plan to have a north to south Barnet wildlife corridor with both east and west branches at its southern end was put to Barnet Council. Here is how Barnet Council was advised that it could green the length of its borough, especially the southern end dominated by major roads. In the late 1970s, I applied for the post of Head of Science at the former St Mary's Upper School, Hendon. During the interview for the post I was quizzed by Barnet's Science Inspector/Advisor about my interests outside of teaching. I mentioned my membership of the Herts and Middlesex Trust for Nature Conservation and explained my enthusiasm for regreening Barnet, especially its southern end. I was mindful of the social disparity between the deprived southern and the much more affluent northern end of Barnet. The Borough's Science Inspector was greatly taken with my vision of a north/south and east/west linked set of wildlife corridors. He asked me to elaborate in some detail on my full regreening proposal for the Borough. He subsequently put my comprehensive plan to Barnet Council.

After quite some time, when funding became available, the Dollis Valley Greenwalk part was developed. Sadly the other half of my proposal, involving the River Brent, was not taken up by Barnet.

Here is why, in 2022, after COP26 (Climate Change Conference) and with COP15 (Biological Diversity Conference) in China due (5), not carrying out the second part of my plan is a potential disaster. Supporting biological diversity in Barnet by means of borough-wide green corridors is now an urgent local matter as it is nationwide one. The aim being to sustain our rapidly declining wildlife and to give pleasure and healthy recreation to people. These corridors will also be vital in helping to mitigate some of the now inevitable effects of climate change. The section of the North Circular Road adjacent to Brent Cross Shopping Centre is a flood risk area that has seen cars submerged in the past. With the expansion of the Shopping Centre and its increased hard surfaces flash flooding and rain bombs from climate change will bring disastrous inundations. Reflect for a moment on the climate-related flooding increasingly occurring in urban areas around the world. Sydney, Australia is a recent example as is Valencia, Spain. Other more enlightened cities are already taking climate mitigating precautions and becoming sponge cities.

"What if a flood could be something we embrace rather than fear? This is the central idea of Prof Yu's sponge city. Conventional flood water management often involves building pipes or drains to carry away water as swiftly as possible, or reinforcing river banks with concrete to ensure they do not overflow. But a sponge city does the opposite, seeking instead to soak up rainfall and slow down surface run-off." (6)

Hull, in this country, has already adopted this sponge approach (7).

Given the Brent Cross area is dominated by concrete flyovers, hard road surfaces and numerous buildings, it will be prone to retaining heat as well as susceptible to flooding. Introducing an extensive area of vegetation at Brent Cross will not only serve as a flood alleviation sponge but it will also have a cooling effect. Thus, plants are also essential in urban settings to help mitigate the effect of climate related heatwaves.

"Healthy urban trees are known to have a cooling benefit. They do this through the release of water vapour, in the process of evapotranspiration. Trees also provide cooling through the provision of shade and because they reflect more solar radiation and store less energy than many artificial surfaces such as concrete and asphalt." (8)

As already pointed out, the River Brent has three sections to consider in any greening and rewilding programme:
the same map with the suggested nature reserve added
1. The Brent Park section simply needs sympathetic management to maximise its ecological value.

2. The section running through the back gardens of the houses of Shirehall Park needs some expert input. An imaginative scheme to win the backing of residents to garden in support of wildlife should be initiated (9). An incentive such as a reduction in rates might be offered, too.

3. The stretch running under Brent Cross flyover and along the south side of Brent Cross Shopping Centre needs major and radical ecological improvement. It will then not only serve as a wildlife corridor but will double as a sponge flood alleviation measure in the face of climate-related severe rainfall.

Assuming the River Brent continues to flow in a concrete conduit along this third stretch, tree and shrub planting is needed on both sides of it. This will include beneath the flyover. 

Additionally, thought needs to be given to reimagining the present concrete river gully. A totally bald concrete ditch makes for a sterile aquatic environment. There are proven ways to dramatically enhance the biodiversity and amenity value of urban rivers. This is being done all over the world and in London, too. For example, the recent restoration of the River Wandle in Croydon (10). Indeed, a stretch of the River Wandle in Carshalton has won a prize (11). Ecological enhancement measures are described in the links provided in the References at the bottom of the page.

I mentioned reimagining. 
Let us take a moment to visualise what enhancements are possible in a sterile concrete gully. They include recesses in conduit walls for plants and birds to occupy as well as gravel on the conduit floor to provide a substrate for plants.

"Simply removing hard riverbanks to increase riparian vegetation and habitat complexity can improve urban rivers and offer socio-economic enhancements as well. Even where flow rates are not reduced, riparian plants can cool rivers, stabilise banks and offer shade to fish and animals. Hard surfaces in urban areas can limit the amount of riparian planting, but even small amounts on highly degraded sites can significantly improve biodiversity. Introducing gravel substrate in highly constrained locations can provide important linkages for wildlife moving between open space and more natural areas." – European Centre for River Restoration (12)
view of a stream with a brick wall with holes in, and gravel in the stream bed

In some rivers and canals, floating islands have been used to increase biodiversity. Click here and scroll to see instant ecological transformations:

All the large, unused car parks south of this stretch of the river should be dug up, planted and turned into an extensive nature reserve. Not only is this ecologically desirable but it provides the climate change mitigation sponge and heat shield that will be vital here in the future. Additionally, such a greening of the redundant current car parking area will improve Brent Cross Town aesthetically. Furthermore, the roadside vegetation of this new nature reserve will serve as a vehicle microparticle and noise filter from the relentless heavy traffic on the North Circular Road.

It takes some imagination and vision to see a Brent Town Nature Reserve sited between the Shopping Centre and the North Circular Road. Yet pause and reflect on how our roadside verges have taken on a vital role in conserving our flora and fauna.

"Often overlooked and undervalued, road verges can be havens for wildlife, both plants and animals. These narrow lanes of land cover a large area of the UK and are crucial habitats for many rare and declining native species.They have matured into valuable wildlife habitats and corridors." (13)

Bear in mind, too, that all our major road arteries will see a massive drop in gaseous emissions and perhaps noise as we transition to electric vehicles.

Picture for a moment the area in front of the Shopping Centre as a green semi-wooded area. The more isolated areas around the various flyover elements could be managed as wildflower meadows. Visualise a sculptured flight of brent geese along the face of the flyover. Imagine some of the flyover pillars decorated with sophisticated botanical murals. Spectacular transformation is possible to give pleasure, to support mental health and to inspire other urban planners.

The images below illustrate how wildlife motifs can both enhance flyovers and draw attention to wildlife indigenous to their location. These photographs were taken at a flyover on interstate highway (I-35E) at Lewisville, Texas indicating species in Lewisville Lake.
large pictures of fish painted on the side of a raised section of motorway
the same pictures of fish, a closer view
Something like brent geese in flight could be adopted for the Brent Cross flyover (being as they are rare winter visitors to the Brent Reservoir)

two geese flying, black heads and necks
Brent Geese

A true green, tree-lined, walk from Brent Reservoir passing between the south side of the Shopping Centre and the roadside nature reserve would be an immense enhancement. It would then continue along Shirehall Park and through Brent Park to meet with the Dollis Valley Greenwalk.

Finally, a borough-wide scheme to engage residents in garden practices that support wildlife could be also initiated (14). Imagine a permanent Barnet biodiversity/climate exhibition at the Shopping Centre. It would aim to win over residents to become participants in greening the whole of Barnet. Additionally, the exhibition would promote the Borough's enlightened approach to creating green cityscapes that address both ecological and climate issues.

Involving the local community in environmental projects has already proven to work elsewhere. Take Woodbridge, Suffolk for example:

"This project is two-fold. On the one hand we want to create a patchwork of spaces in people’s gardens that are dedicated to, and focus on encouraging, nurturing and protecting biodiversity, that together form the “Community Nature Reserve”.
On the other hand we are trying to find out where we already have wildlife corridors, which will help us to study and improve biodiversity in our beautiful part of the world." (15)

The London Borough of Barnet has a rare opportunity, with the juxtaposition of the River Brent and the Brent Cross flyover section of the North Circular Road, to demonstrate how the most unlikely ugly urban site can be dramatically changed. Brent Cross would be wonderfully enhanced by a 'sponge' nature reserve. Such a transformation would be an exemplary ecological and climate change triumph to inspire cities everywhere.

Finally, there is a wider prospect to my proposal. Already, plans for London's hidden rivers to be resurfaced are afoot (16). Indeed, this has already happened in some places, e.g. the River Wandle in Wandle Park, Croydon (17). The River Fleet running from Hampstead Heath south to the River Thames has been mentioned, as has the River Brent where it passes through Wembley. This holds the exciting future prospect of outer boroughs, such as Barnet, feeding Central London with wildlife diversity through its river corridors.

Mindful of both global warming and a worldwide decline in biodiversity, I put forward my proposals for borough-wide wildlife corridors very early in my science teaching career. I have spent a lifetime involved with children. Now, half a century later, I am still passionately campaigning for our young people's future survival on a restored planet Earth.

With all good wishes for a more beautiful urban world

Dennis Ayling

Dedicated to my grandchild, Damon Atticus Allison

The following article concerning the Brent Reservoir (Welsh Harp) has just come to my attention. This area of wetland is a Site of Special Scientific Interest. The article is indicative of the extreme and shameful neglect of the whole Brent River system, especially in the face of the global biodiversity crisis.


(1)  Rachel Carson's Silent Spring published in 1962

(2) In 1979 a US National Academy of Sciences report

(3) This spring the IPCC released the third part of its Sixth Assessment Report 

(4) UN's call to make both local and global transformative change

(5) COP15 delayed until August

(6) Sponge cities embrace floods

(7) Hull's aqua greens are another example of the urban sponge approach

(8) How trees cool towns

(9) Wildlife Gardening

(10) Restoring the River Wandle

(11) River Wandle wins prize

(14) Creating wildlife pathways

(15) Woodbridge's community environmental projects

(16) Restoring London's Rivers, 2008

(17) Restoring London's Rivers, 2016

Deep Adaptation recommended reading

1. Book “Deep Adaptation: Navigating the Realities of Climate Chaos”

The report, edited by Jem Bendell and Rupert Read, provides the latest update over a range of areas, UK based but with a strong global & local orientation and recognition of the exacerbation of inequalities brought about via climate change.

It provides an up-to-date scientific assessment which is strong enough for editors and contributors to accept that, painful though it is to write or say – and harder still to accept – we are facing the inevitable or probable collapse of civilisation as we have known it (the two authors differ on whether ‘inevitable’ or ‘probable’). This is attendant, of course, with feelings of grief and despair, fully acknowledged in the book. In fact, our actions emanate from our feelings not our intellect.

2. Online article “What next on climate? The need for a new moderate flank”

The necessity now is therefore for deep or transformative adaptation, explained briefly in an article by Rupert on the need for a ‘moderate flank’ of which BCAG might well see itself as a part:


Barnet Sustainability Framework Note December 2021

Update 23 December 2021

  • Barnet’s Sustainability Strategy Framework was unanimously passed through at their Policy and Resources Committee meeting of 9 December (details below).
  • A number of points raised by Councillors (highlighted in the press story from the Barnet Borough Times Barnet Council ‘to achieve net zero emissions by 2030’) were set out in our BCAG briefing paper that we posted online ahead of the meeting, see below.
  • The report also states that “The council will carry out public engagement with residents to allow them to shape the development of the strategy in the new year. A public consultation will then be held in the spring, before the strategy is adopted by the council.” BCAG will be looking to take an active role in responding to this public consultation.

BCAG will be reviewing the Sustainability Strategy Framework in our January 2022 online meeting: a date for this meeting will be announced shortly. We look forward to seeing you then.

At Barnet Council’s Policy and Resources Committee (PRC) meeting, taking place on 9 December 2021, the agenda will include some long awaited detail on Barnet’s forthcoming Sustainability Strategy, said to be released in the new year. BCAG have produced the forthcoming briefing note on the Framework document and sets out some key requirements to ensure the Strategy is a success.

Download Barnet Sustainability Framework Note December 2021 (PDF 575 Kb, 6 pages)


Local Plan Briefing Note

Barnet Councils new Local Plan sets the Council’s vision for growth and development in Barnet over a 15-year period (2021-2036). It is out for consultation and representations until 9th August 2021.

Update 29 September 2021: The new Local Plan has now moved on to the next stage following the consultation on the Regulation 19 Draft Local Plan. You can follow progress on the Barnet council web site.

Update 10 August 2021: see BCAG response to local plan.

Is it important?

Yes! The Development Plan is the basis upon which planning applications in the Borough will be determined. In the next 15 years that means some 60,000 decisions taken by the Council involving the development of new homes, the amount of affordable housing, loss of open space, new businesses, how Barnet will look, its ‘character’, how it tackles Climate Change, biodiversity, wildlife, transport, energy etc will all be affected by it.

This version of the Local Plan is a draft document specifically produced to enable representations to be made on the draft plan that will then be considered by an independent Inspector at the examination stage. Written representations and appearing at the public examination are supposed to carry the same weight.

The draft plan is a technical document but do not let that put you off. If it does not say what you think it should – or says something you think it shouldn’t then make a representation. If you want to change Barnet’s policy at this stage keep in mind that you should have good grounds and sound evidence to back up what you say – just having an opinion won’t wash!

What key areas does it cover?

Pretty much anything and everything to do with the built and natural environment in Barnet. Chapter headings include:

  • Barnet’s Vision and Objectives
  • Growth and Spatial Strategy
  • Housing
  • Character, Design and heritage
  • Town centres
  • Community Uses and promotion of health and well being
  • Economy
  • Environment and Climate Change
  • Transport and Communications

How is the plan structured?

The Plan contains:

  • 309 Pages
  • 12 Chapters
  • 3 Appendicies
  • 52 Policies and supporting text
  • 67 Site Specific proposals

What is the key driver behind the plan?

By 2036 Barnet is looking at a projected population increase of over 50,000 up to a total of 452,000. This will need a minimum of 35,460 new homes (2,364 new homes per annum). Barnet’s Plan seeks to enable this growth and deal with the implications of it.

Are Barnet’s parks, open spaces and biodiversity protected?

The policy approach should be strengthened. The important part of the plan – the one in daily use by planners in determining applications and considered by developers is the Policy. In this plan the supporting text often reads stronger than the policy.

[The original document contains copies of eight policies in the appendix which appear to have a significant bearing on open spaces, biodiversity and parks in the borough. These are omitted from the web version]

Areas to consider for representations.

  • Oppose “low value, low quality” provisions in Policy ECC04. We should be protecting and enhancing all open space in the borough not allowing development on it. The ‘evidence’ to justify this policy is out of date, extremely subjective in its judgements and should not be used. Recommend removal of this element of the policy.
  • A Regional Park for Barnet based on the Green Belt. The idea has been around for many years but the there is nothing specific on how and when it will be delivered. The messages given in the plan on this are garbled. Recommend much clearer statement on how this is to be progressed.
  • Hedges get limited mention and Trees are subsumed within generalised policies. Recommend strengthened, separate policy on dealing with Trees and hedgerows.
  • B-lines – No mention of these pollinator highways, promoted by Buglife as part of the Governments pollinator strategy. The north-south corridor through London cuts across parts of the borough including parts of Finchley and New Southgate where there is a growth area and a number of site specific proposals. Recommend add B-lines to Key diagram, proposals map and covered in appropriate policies and site specific proposals.
  • Temporary use of development sites for green space. There is a policy on ‘meanwhile uses’ for temporary housing but not on potential for open space. Recommend new policy supporting temporary use of development sites for open space and community growing projects.
  • Front garden use for car parking. No policy on prevention of turning front gardens into car parking on those roads where planning permission is required. Recommend addition of policy opposing use of front gardens for car parking.
  • Support reasonably strong policies protecting Green Belt and Metropolitan Open land. The likelihood is that these policies will be attacked by developers.
  • Consider whether you should be promoting sites/ideas near to you. Two that I shall be promoting are: Creation of a new park in East Finchley in an area of open space deficiency and designating Barnet owned land adjacent to a local park as an extension to the park.

There are probably a lot more ideas that could and should be raised.

Use the forms provided.

Barnet are using a form for representations based on nationally prescribed ones. Do use them. It makes life easier all round.

Roger Chapman

Chair, Barnet Green Spaces Network

6th July 2021

The appendix of the original document contains the text of the following policies relevant to Open Space. These are omitted from the web version.

  • POLICY BSS01 Spatial Strategy for Barnet
  • POLICY GSS13 Strategic Parks and Recreation
  • Policy CDH07 Amenity Space and Landscaping
  • Policy CHW 02 – Promoting health and wellbeing
  • Policy ECC02A Water Management Policy
  • Policy ECC04 –Barnet’s Parks and Open Spaces
  • Policy ECC05 – Green Belt and Metropolitan Open Land
  • Policy ECC06 – Biodiversity

Barnet’s air quality. Why we should be concerned.

by Peter Piper, updated 4 October 2021

[Editor’s note: we have been contacted by Mums For Lungs, and you may like to work with them if you want to campaign about air quality in London.]

From 2016 to 2019 Central London experienced significant improvements in air quality [1], As a result there was a 97 per cent reduction in the number of inner London schools exceeding legal pollution limits – from 455 in 2016, to just 14 in 2019 – as well as a 94 per cent reduction in the number of these areas exceeding legal limits for nitrogen dioxide (NO2). It is predicted that this should increase the average life expectancy of a child born in inner London in 2013 by six months [1].

Despite this, the levels of air pollution in London are still far too high and the improvements in air quality in inner London have not happened in many outer boroughs. An Imperial College study concluded that toxic air had contributed to the deaths of more than 4,000 Londoners in 2019 [1], the boroughs with the largest number of air pollution related deaths in 2019 being Bromley, Barnet, Croydon and Havering [1].

That pollution-related deaths are higher in outer boroughs is partly a reflection of the higher proportion of elderly residents in these boroughs. Older people are generally more vulnerable to the impacts of air pollution. We know that air pollution increases the severity of other health problems, like heart attacks, strokes, diabetes and high blood pressure. Other factors are also involved. Londoners exposed to the worst air pollution are more likely to live in deprived areas and to be from Black, Asian and Minority Ethnic communities. There is also evidence linking air pollution to an increased vulnerability to the most severe impacts of COVID-19 [2].

The expanded ULEZ may exacerbate the problems Barnet faces when dealing with air pollution.

The success of the existing central London Ultra Low Emission Zone (ULEZ) gives confidence that the expansion of the ULEZ on 26 October 2021 [3] and tighter standards for heavy vehicles across the entire city will deliver wider benefits. It is predicted that this will prevent more than one million hospital admissions over the next 30 years, thus saving the NHS around £5 billion and [1,3]. Barnet Council has produced detailed information as to the parts of the borough most affected by air pollution, as part of its plan detailing actions it aims to deliver between 2017 and 2022 in order to improve local air quality in the borough [4].

The boundary of the new, expanded ULEZ will be at (but not including) the A406 North Circular [3]. Unfortunately as much of Barnet lies outside of this new ULEZ, this ULEZ expansion is unlikely to lead to a substantial improvement of air quality in the borough. Instead it may lead to many residential streets near the A406 in Barnet becoming more congested and polluted, as drivers try to avoid the charge. There are also the highly polluted trunk roads north of the A406 such as A1, M1, A41, A5 and A1000 that are not in the new ULEZ and will not therefore see much reduction in vehicle pollution.

BCAG would like to see a prioritisation of Barnet Council’s stated objective of exploring the option of increasing the ULEZ to cover the whole of Barnet. This could potentially have the most significant impact on improving air quality in the borough. GLA evidence for ULEZ expansion predicts a 31% reduction in NOx emissions in Barnet by 2025 if all of Barnet were to be in a ULEZ, but only an 8% decrease with just the area south of the A406 is in the new, expanded ULEZ [3].  Year-on-year diffusion tube measurements NO2 at 15 sites across Barnet show a moderate 7 year decline [4] (the more dramatic decline 2019-2020 probably being due in large part to the Covid lockdown, strong winds or high rainfall over this period). It will be interesting to see whether the diffusion tube measurements of NO2 at the 15 sites currently being monitored in Barnet [4] change significantly with the expansion of the ULEZ.

Furthermore, while expanding the ULEZ will help reduce NO2 levels in inner London (the latter mainly due to diesel exhaust), we will still be faced with the problem of breathing in unacceptable levels of PM2.5 particulates (ninety-nine per cent of London does not meet WHO recommended limits for PM2.5 – the particles most dangerous for health). Expanding low traffic neighbourhoods might not always solve this PM2.5 problem, since they can lead to traffic being diverted from more affluent “leafy” roads to busier, potentially less affluent areas. An Imperial College study of pollution levels in the Marylebone Road during lockdown found that particulate pollution from tyres and brakes did not decline with the reduced volume of traffic, since this traffic was now moving faster.

The prospect for real-time monitoring of the pollution in Barnet.

Barnet Council has produced a detailed pollution map of the borough [4]. However pollution levels at all of these sites will vary considerably over time with changes in traffic levels, weather conditions etc. What is needed is up-to-date information provided by continuous monitoring of pollution throughout the day (“real-time” monitoring). For the past few years Barnet has been continuously monitoring NO2 and PM particulates at two sites (Tally Ho and Chalgrove School)[4], the data being available on the Air Quality England Website : (

BCAG would like to see Barnet increase the information available to the public through “real-time” monitoring of pollution by: (i) becoming included the London Air Quality Network [5] and (ii) expanding its participation in the Breathe London real time monitoring of pollution [6].  Breathe London is currently placing sensors for continuous monitoring of PM2,5 pm10, temperature, humidity and pressure (not NO2)) at 300 sites across London [6] (see ). Although not stated in Barnet’s latest Updated Air Quality status report [4], 4 of these air quality monitors (called Node-S) were recently installed in Barnet (at Wessex Gardens Primary School, Orion Primary School, Martin Primary School and Cat Hill allotments). This welcome inclusion of Barnet in Breathe London will allow its residents, especially those with respiratory problems and those with children, to use the to know when best to negotiate Barnet’s pollution hotspots (the sensors continuously monitor PM2,5 pm10, temperature, humidity and pressure [6]. Furthermore, in addition to these Breathe London sensors, boroughs and other organisations will be able to ‘buy in’ extra sensors to the network at a greatly reduced cost [6]. Since the sensors cost only £40-50 each it is hard to see how failure to introduce a network of them can be defended simply on the basis of its cost. Instead, such a network of sensors could supply online localized air pollution data in real-time for multiple sites in Barnet where residents are potentially exposed to pollution. Residents will then be able to use the CityAir app to minimise pollutant harm to themselves and to their children, Policymakers can also identify problem areas and take steps to protect those who are most at risk, including school children and the residents of lower-income neighbourhoods. The technology is now available. BCAG believes it should be introduced more widely as a matter of priority.

Improving air quality is vital for our children’s future.

Children are one of the worst affected groups when it comes to air pollution [8-10]. According to Unicef UK, children are growing up breathing hazardous levels of toxic air across 86% the UK. It stunts their lung development and increases risk of asthma and pneumonia. Furthermore children breathing toxic air are four times more likely to have reduced lung function in adulthood. All policymakers should take necessary action to protect children especially from road transport emissions. A recent study found that children are most exposed travelling to school, not in the classroom [9]. Note how dramatically the sudden surges of NO2 in the environment of Barnet’s Chalgrove School disappear during the school summer holiday period :-

graph showing nitrogen dioxide levels from October 2020 to September 2021

BCAG would also like to see the right air quality standards – legally binding WHO recommended limits on pollutants – to be achieved by 2030, adopted in the Government’s new, but at present underwhelming, Environment Bill. This will be a once-in-a-generation opportunity to rebuild our cities and economies to be greener, fairer, and more sustainable. However under the Government’s current plans, air pollution in the UK is expected to remain at dangerous levels for at least another 10 years [7]. The estimated cost to health and social care services is upwards of a staggering £2 billion [8], as a result of its impact on heart disease, stroke, lung cancer and childhood asthma. The sources of pollution around London schools have been subjected to detailed analysis [10].








[7] Department for Environment, Food and Rural Affairs: Clean Air Strategy

[8] Public Health England: Estimation of costs to the NHS and social care due to the health impacts of air pollution,





Reducing carbon emissions from Barnet’s homes

by Syed Ahmed

A great blog by housing energy efficiency specialists Parity Projects on the workforce required to see homes on a zero carbon pathway – and the retrofit tasks and skills required to upgrade homes. As a reminder of the challenge just in Barnet – never mind the UK – there are 160,000 homes in the borough. The latest data shows that through the Mayor’s energy efficiency scheme have supported the retrofit of exactly 200 homes in the borough since 2016 (see data here). The Energy Company Obligation (ECO) programme is the Government’s main household energy efficiency programme. The latest data published by the Department of Business Energy and Industry (BEIS) shows that just over 5,000 homes received an energy efficiency improvement since this new phase of the scheme began operation in 2015. (See BEIS statistics for March 2020 here – tab 4.4 of the spreadsheet there).

So – over the past five years or so, being generous, some 5,500 homes in Barnet have had some form of energy efficiency improvements installed through a targeted programme. In addition – approximately 1.6m boilers are replaced every year across the UK. Barnet’s likely share of this would be about 10,000 or so per year – 50,000 over the past five years – which would all have improved the energy efficiency of homes.

Whilst this level of activity is to be welcomed, none of the work currently being undertaken in existing homes achieves anything near the zero carbon standard needed to fully address the climate emergency. Much deeper retrofits are required, and the scale of action needs to be significantly increased if we are to reduce emissions from the domestic sector across Barnet and all other parts of the UK.

Prioritising energy efficiency in Barnet’s homes will boost opportunities for local building services companies, insulation firms, plumbers and other associated trades. These are exactly the SMEs currently being hammered during the lockdown. Boosting energy efficiency will be good for Barnet’s homes, for tackling fuel poverty, for resident’s health and supporting local businesses and employment.


Post -Covid 19: What Will Be The New Normal?

by Tony Sarchet

A crisis as serious as the current pandemic has put normal life on hold. At the same time, it raises certain concerns about exactly what kind of normal life we should be hoping to return to once the crisis has passed. A lower carbon one would be nice.

Here are a few questions that have occurred to me, prompted by the changes we have all been living through:

Now that we’ve all been forced to get used to conducting meetings from home using platforms such as Zoom, will companies in future enthusiastically revert to spending large sums of money sending their employees across the country, continent or world to check into expensive hotels in order to transact business? Or will some proportion of them decide to forego the jet lag, the travel time and the expenditure? What will this mean for projected future airline capacity? Will the money these airlines are already pleading the government to bail them out with turn out to be money well-spent?

And now that companies have been forced to make arrangements for many of their employees to work from home, how many of them may occasionally prefer not to have to undergo the crowded and stressful daily commute? Will this have an impact on future passenger numbers?

And now that many smaller companies which previously supplied produce exclusively to restaurants and cafes have started offering home deliveries of fresh fruit and vegetables of impressively good quality, how much of a chunk of the big supermarkets’ consumer business might they retain? And wouldn’t this be good for both growers and wholesalers, and maybe even help to reduce food miles?

The new normal seems to be a place where there is such a thing as society, where people in medicine and the caring professions are regarded as heroes. I wonder what else will be discovered – or rediscovered?