Street trees – a public health issue

Shaw Street in Petersham is a good example of a good green street that has a lot of traffic. It’s not a wide street, yet tall reasonably closely spaced street trees have been planted.

We know that vehicle-related pollution & particulate matter is a public health issue as these can cause respiratory & heart illnesses/diseases & increased incidences of death.

In 2010, research from 700 worldwide health-pollution studies found that traffic pollution within a 500-metre radius of a major thoroughfare was likely to –

• Exacerbate asthma in children
• Trigger new asthma cases across all ages
• Impair lung function in adults &
• Could cause cardiovascular illness & death.  See – http://bit.ly/QpiYx6

We also know that street trees help improve air-quality by removing some of the vehicle-related pollution & particulate matter from the air.

Thanks to research published in June 2012 by researchers at the Lancaster Environment Centre at Lancaster University http://bit.ly/Pk4skG  we now know that that this level of pollution removal is actually much higher than previously thought, making humble street tree & other street vegetation more important than ever for human health.

Previous studies thought street trees captured less than 5% of air pollution from vehicles. The small percentage may have given an out for Councils not to have street tree planting as a priority.  However, this study from the Lancaster Environment Centre has shown that –

• “increasing deposition by the planting of vegetation in street canyons can reduce street-level concentrations in those canyons by as much as 40% for nitrogen dioxide & 60% for particulate matter.
• Deposition rates of nitrogen dioxide & particulate matter to vegetation are much higher than those to hard, built surfaces.
• Substantial street-level air quality improvements can be gained through action at the scale of a single street canyon or across city-sized areas of canyons.
• Vegetation will continue to offer benefits in the reduction of pollution even if the traffic source is removed from city centers.”

I love what this property in Stanmore has done with the area along the laneway outside their house. You see this type of area often & mostly they are left to the weeds.

What wonderful research.  It clearly shows that the budgetary spending by Councils needs to be much higher for planting street trees & increasing the urban forest as trees are very much a public health issue.

Adding street trees & other vegetation should be a priority along main roads, secondary main roads & along shopping strips.  Verge gardens, pots filled with plants, green walls & hanging baskets are examples of vegetation that help to remove vehicle-related particulate matter.

As we know, street trees & other greenery also improves human happiness as well as increasing spending by around 11% along leafy shopping strips (by happy people).  Concentrating only on diet & lifestyle issues is not the only consideration public health should be looking at. Green streets full of street trees & other vegetation where trees cannot be planted is an important & vital step to ensuring a population can remain healthy.

Busy Glebe Point Road Glebe is a great example of a green shopping strip. It looks like this for most of its length. Where trees can’t be planted the City of Sydney Council has suspended large hanging baskets or reclaimed a parking space to plant a street tree. It look great & feels great too.  

Marrickville Road shopping strip with its few deciduous street trees always strikes me as bare

This section of very busy New Canterbury Road Petersham has looked like this for at least 3 decades.  

 

 

 

Melbourne & the Great Tree Removal

In news just in, the Victorian Labor state government has ‘refined’ rules regarding street trees & power cables.  The new law, “set minimum clearance space” around cables. It ranges from 30cm to 3.5m, depending on the type of powerline.” The energy companies must be planning a big celebration party.

“Banyule Council deputy mayor Jenny Mulholland, whose municipality includes Ivanhoe & Eaglemont, said many of Melbourne’s leafy streetscapes would be reduced to rows of tree stumps. She said 75,000 trees would be affected, costing the council $3 million, or the equivalent of a 6% rate rise.”

Street trees in Darlinghurst

Quite understandably, many of Victoria’s local Councils are very unhappy about the new rules, as the fine is $30,000, which I presume will be for each tree that breaches the clearance space.  Councils will need to spend millions of dollars pruning & removing larger trees just to comply with the initial stages. Then there will be ongoing costs. This is death to most local government budgets.

Here is where it gets really interesting.  Melbourne is famous for its street & park trees.  Having lived there I can attest that is it is a lovely green city with large street trees everywhere.  Most ordinary streets in Melbourne are what we in Sydney would call ‘an avenue of trees’ & regard as special streets.  The city prides itself on its street trees & it has lots of urban wildlife.  People & businesses take care of the street trees.

We visited Melbourne recently & it seemed that there were more trees than when I lived there.  There was no rubbish around trees in the areas we visited, trees were not in cages, branches were not snapped off & main shopping strips were full of large leafy trees.  Large street trees in the middle of the road is the norm.  The general height of street trees in Melbourne is much higher than in Marrickville LGA.   Most street trees reach well above the gutters of buildings & many are higher than the buildings themselves.

Quite simply, the city & surrounding suburbs looked glorious. Speak to any Melbourne person about the street trees & watch their face light up. They love them.

It makes a big difference to how a city & its suburbs work when there are a lot of street trees. People are drawn to eat outside. Melbourne is a coffee-drinking culture.  There are hundreds of cafes with people sitting at tables eating & drinking under street trees.  They were doing this as a norm 30 years ago, while here in Sydney it is a relatively new thing.

Street trees in Liverpool Street Sydney

Many of the street trees of Melbourne are deciduous so, like Canberra, they have visible seasons with autumn colours, bare trees in winter & spring growth. Because much of Melbourne is flat terrain, trees are visible in the distance. They also bring much beauty to industrial areas or areas where the quality of the buildings is not so attractive.

Take the trees away & you have removed much of what makes Melbourne special. The city won’t recover & the loss of street trees will affect tourism in a major way.

Add the fact that Melbourne is very hot in summer. Most years they have a few days of constant heat-wave conditions.  Take the street trees away & the heat island effect is going to be horrendous. Then there is winter where the winds come straight from Antarctica & are bone-crunching freezing. With fewer street trees, the wind won’t be diffused & will roar around the streets. The heat will be hotter & the cold colder.

To me the Victorian Energy Minister Peter Batchelor has made a really strange decision. In one foul swoop he will seriously affect tourism for the city, he will ensure rates rise dramatically, he will anger the Councils & seriously anger the people. How will they accept that their beautiful streets are going to be denuded & made ugly? The process may start, but I doubt it will last long once people & industries start noticing the impact & the loss of quality of life.

Has the Minister not heard of global warming or climate change? Just how hot does he want the city of Melbourne & its suburbs to become?  Imagine the follow through as more people go to hospital with heat, respiratory & cardiac related illnesses.

Hills Figs in Jersey Street Marrickville

The real winners of this decision are the power companies & the retailers of air-conditioning units.  Every residence will need at least 1 air-conditioning unit & sales will go through the roof. More electricity will be used & power costs will increase dramatically. The city will pump out CO2 making us proud polluters in the world stage.  Urban wildlife will die. The city will be dirtier from particulate matter & dust that usually gets picked up by the trees.  People will be angrier. Graffiti will get worse as it is known to be high in areas that have few street trees. Rates will rise again just to pay for graffiti removal & state taxes will rise due to the increased pressure on the health system.

It’s astounding that this ‘rule’ comes out of the mouth of a representative of the people who is supposed to be doing things for the people & for the benefit of the people.  While the rest of the country & the world gets its act together about trees in urban areas & greens their cities, Melbourne will be doing the opposite.  Right now Melbourne is a role model of what a green city looks like.

Street trees in Salisbury Road Stanmore

Then the National Broadband Network will roll out.  If they don’t put the cables underground, they will put them on the power-poles just like Optus did.  They will probably want their broadband cable positioned another metre below the Optus cable & then all the street trees will have to be removed.  Great move.

In a senate debate, “To bury or not to bury,” the following was written – “To provide optical fibre cables aerially, the NBN Co will need to either use existing electricity utility infrastructure, or to build their own poles where there are none in existence. Aerial cabling is most likely to be used in existing, or ‘brownfield’ areas, where telecommunications & other infrastructure already exists. Extrapolating from that assumption & taking guidance from the Tasmanian roll-out, the committee believes that aerial cabling may be deployed over the vast majority of the 90 per cent FTTP footprint.”

http://www.aph.gov.au/senate/committee/broadband_ctte/third_report/c04.htm

I can’t imagine the people of Melbourne will just sit back & allow their suburbs be made into wastelands. I will watch how this pans out & report back on the most interesting bits.  Good luck Melbourne.

http://www.heraldsun.com.au/news/victoria/melbournes-famous-tree-lined-streets-could-be-stripped/story-e6frf7kx-1225941423229

Particulate matter & Type 2 Diabetes

Street trees along the City of Sydney Council end of King Street Newtown proving it can be done

We know that the particulate matter in air pollution comes from vehicles & coal power stations causes respiratory disease, including asthma in both children & adults as well as heart attack related death. Now 2 new research studies done by entirely different research groups in Germany & the USA have shown that particulate matter also increases the incidence of Type 2 Diabetes.

… the new data provide important & more rigorous evidence that real-world pollution may be tampering with blood sugar control in a large & growing number of people.

The researchers used proximity to roads — where vehicles would be a major pollution source — as a proxy for exposure to fine particulates. Women who developed diabetes were more likely to have lived nearest to heavily trafficked roads.

Compared to the 25% of women living farthest from busy roads, the relative risk of developing diabetes was 15% higher for the 25% of women living closest to major roadways.

There is a growing body of literature suggesting that people with diabetes may be more susceptible to the harmful effects of air pollution.

All the more reason why we need to start planting more street trees, especially on & around main roads. This issue is fast becoming one that will have serious impacts on our health system.  It makes sense to use nature to try to lessen the impact of our 21^st Century lifestyle as money spent now may help mitigate the financial cost of disease in the future.

It’s well worth reading the full article – http://www.sciencenews.org/view/generic/id/63971/title/Air_pollution_appears_to_foster_diabetes

I wrote about this issue here – http://savingourtrees.wordpress.com/2010/06/29/living-close-to-a-main-road-is-bad-for-your-health/ &

http://savingourtrees.wordpress.com/2010/09/21/trees-particulate-matter/

Trees & particulate matter

Marrickville Council section of Parramatta Road on right. Leichhardt Council on left

An article was published in Reuters Health this week about research done by Dr Robert A Silverman of the Long Island Jewish Medical Center in New York.  Dr Silverman studied the link between particulate matter (pollution from vehicles & coal-fire power plants) & 8,000 heart attacks in New York City between 2002 & 2006.

“As the levels of particulate matter air pollution increased, more cardiac arrests occurred.”

“When they looked at fine particulate matter (particles 2.5 micrometer or less in size), they found that the risk of having a deadly cardiac arrest rose by between 4 & 10% with every 10-microgram-per-cubic-meter increase in fine particulates.” The current EPA standard of 35 micrograms per cubic meter is grossly inadequate.

“Being indoors may offer only limited protection since small particles can penetrate into buildings and homes.”

As far as I can ascertain, there are only 3 things that stop particulate matter –

• removing all vehicles from the roads,
• closing down coal-fire power stations &
• trees.

In 2003 there were 204 million vehicles on the road in the US.  This increased to 246 million vehicles on the road by January 2010.  In 2009, there were 50 million more vehicles on US roads than 6 years previously, though in 2010, it dropped to only 46 million more. In comparison, China is estimated to have in excess of 70 million vehicles on the road by the end of 2010 & expected to have over 200 million by 2020. Still they wont have caught up with the Jones’s.

Australian statistics were hard to get though I did find that 13.2 million vehicles, including motorcycles, were registered in Australia at 31 March 2003.  I would expect the numbers to be much higher for 2010.

Worldwide it is predicted there will be 1.2 billion vehicles on the road by 2015.

Only the cost of petrol or a severe shortage of oil is going to bring down vehicle use numbers.  You can see why most cities are trying to encourage public transport use, walking & cycling.

As for coal-fired power stations, Australia does not look like it is planning to reduce or stop them with up to 12 new coal-fired power stations planned across the country.  Unfortunately, in NSW they intend to mine for coal in the small bits of land that is Koala habitat.  If you are interested in this – https://www.savethekoala.com/ is a terrific resource & Deborah’s (Tabart) Diary gives regular updates about the Koala situation in Australia https://www.savethekoala.com/deborahtabartsdesk.html

Everyone loves this end of Crystal Street because of the large trees

Lastly, we come to trees. Trees remove up to 60% of street level particulate matter & dramatically improve air quality, which is why their presence is so important in high traffic areas.  The more trees in an area, the better the air quality. Trees also absorb other pollutants such as Ozone, Nitrogen Dioxide & Sulfur Dioxide through their leaves.

A street tree removes 9 times the amount of air-born pollution from passing traffic than does a tree on a nearby property.  Street trees also improve the air that enters people’s homes, especially important as particulate matter penetrates buildings even when the windows are closed.

Large trees provide the most benefit as they provide greater absorption of particulate matter.  Small stature trees that are the perhaps the most common sized tree across Marrickville LGA have far less ability to do this.

The issue of pollution from vehicles is becoming an issue that is too hard to ignore. I am of the opinion that many of our roads in Marrickville LGA are quite dangerous in this regard due to the large volumes of traffic every day. Even small suburban streets that are more like lanes can have in excess of 7,000 vehicles/day.

If the Marrickville Metro expansion goes ahead there will be a potential loss of 142 trees & an extra 4 million shoppers a year. You can just imagine the air pollution around the surrounding residential streets & the planned plaza.

Parramatta Road & the Princes Highway are mostly treeless in the section that is under the governance of Marrickville Council.  It’s not just a matter of beautifying areas that are seriously lacking in aesthetic beauty, it is a matter of public health.

Parramatta Road under the governance of City of Sydney Council

This problem is not going to go away.   I think the NSW state government should allocate money to Marrickville Council to plant trees on these main roads. This is a major project requiring funds that Marrickville Council cannot afford. For this reason it is imperative that the state government fund it as a special environmental project.   It will save the government much greater amounts of money in the long run as people living in Marrickville LGA may just end up in the health-care system.

The population of Marrickville LGA is going to expand. We will all be living & shopping closer together & despite what the authorities say, I believe that the ‘culture of the car’ is not over by a long-shot.  If I am correct, then the issue of pollution-related illness from vehicles is going to spike in the Inner West & we are going to need many more trees to try & lessen the particulate matter that the residents & workers are breathing in.

On 29^th June 2010 I posted ‘Living close to a main road is bad for your heath’ which discusses this issue further.

http://savingourtrees.wordpress.com/2010/06/29/living-close-to-a-main-road-is-bad-for-your-health/

To read the article with a link to the research paper – http://news.yahoo.com/s/nm/20100916/hl_nm/us_pollution_cardiac