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Sydney Water plans for bank restoration at Cup & Saucer Creek
The restoration will give a home for these Cormorants. They are sitting at the point on the diagram above.
I received some really exciting news about the Cooks River from Mudcrabs. Sydney Water recently spent over $3-million removing more than 6,000 tonnes of silt from the Cooks River & now intends to naturalise over 1km of the riverbank at three sites. They have called for tenders & work is planned to start in early 2013.
The three areas of riverbank to be targeted are at Whitten Reserve in Belfield, Flockhart Park to Beamish Street Campsie & the area in front of & adjoining Cup & Saucer Creek Wetland at Canterbury. All planning diagrams for the three sites show the planting of many new trees. This is a bonanza for the health of the Cooks River, the wildlife & the community.
From Sydney Water’s website - “Riverbank naturalisation can take different forms, but generally involves the removal of some, or all of the steep concrete channel bank & creating a more gently sloping bank. This is stabilised with native plants, trees & rocks. Naturalisation creates a softer landscape feel & can greatly improve the riverbank habitat for native birds & other animals. Wetlands can also be established as part of the naturalisation process. Wetlands have a significant role in improving the river’s ecology & health by treating stormwater runoff from streets & industrial areas, before it enters the river.”
Last year the Cup & Saucer Creek Wetland won the Highly Commended award at the NSW Stormwater Infrastructure Association Annual Awards for Excellence. Sydney Water deserved to win. The wetland cost $900,000 & was money well spent. Cup & Saucer Creek Wetland is a fantastic achievement & is very beautiful. Lucky are the people whose properties back on to or face the wetland. I’d love to be waking up to the sound of the birds in the morning.
From being a lawn with a couple of trees, it is now an important habitat area filled with waterbirds & other life, including turtles. On top of this, the wetland cleans the stormwater coming down the Cup & Saucer Creek channel before it enters the Cooks River. The community will benefit from the new works too, as we have already benefited from the environment of the Cup & Saucer Creek Wetland.
The habitat around Cup & Saucer Creek Wetland from the pedestrian bridge at the Sugar Factory to Mary McKillop Park will be extended & the lawn removed. This is a good length in an area filled with waterbirds. There will be new viewing platforms, new seating (great because there isn’t much), saltmarsh plants & gravel paths, plus many new trees. The area from Burwood Road to Beamish Street will also have new trees, saltmarsh plants, a viewing platform & a gravel footpath. Similar additions are planned for the area at Whiddens Reserve.
Slowly this beautiful river will be repaired from the terrible damage inflicted upon it over the last century. The restoration works by Sydney Water will be a better legacy to bestow on future generations & I am quite excited about it.
You can download the plans here – http://bit.ly/RriIM7
For more information see Sydney Water’s website – http://bit.ly/SmzOgl
Sydney Water plans for the area from Flockhart Park to Beamish Street
Sydney Water plans for Whidden Reserve
A flock of Fairy Martins are busy building mud nests under the Illawarra Road bridge in Marrickville.
1. Tree collector Enzo Enea has opened his Tree Musuem in Rapperswil-Jona Switzerland to the public. The museum has a collection of 2,000 different species of trees gathered over the past 17-years & is in the grounds of a 14th Century monastery set on 2.5-acres. Brilliant idea. I bet it will be very popular. http://bit.ly/lr4MBJ
2. So simple, I wondered why it wasn’t the norm already. Designer Danor Shtruzman has come up with a way to water street trees & verge gardens by directing any water that hits the footpath to the plants. Grooves set in the footpath direct water to drains, which then take the water to the roots of plants or trees. Nice. http://bit.ly/OrSbLt
3. The city of Copenhagen in Denmark has unveiled plans to create the first climate-adapted neighbourhood & I love it. 20% of the street area (around 50,000 sq mts) will be reclaimed for trees & plants. Stormwater will be directed to planted areas reliving the sewerage systems of a great amount of water when it rains. Bicycle paths will also act as storm water channels. There will be water towers, green roofs, urban gardens & green houses. “….the project will instead operate with the city’s visible surface & make the city greener, so that water is both delayed & the urban spaces are simultaneously transformed into wondrous places for the city’s residents to hang out or exercise.” http://bit.ly/PZFn2b
4. A campaign has been launched to raise $4 million dollars plus to replace the forest that was burnt in the Lost Pines State Park & surrounding areas in Texas. 95% of the forest was lost to the fire. The plan is to plant 4-million trees. “Foresters say it will be at least 30 years before the loblolly pine seedlings grow to resemble a forest.” Quite a sad statement really when you think how easily our forests are cleared for woodchip. http://sacb.ee/Ov80od
5. Sadly, about 301 million rural trees have died in Texas as a result of the 2011 drought. Estimates are that a further 5.6 million trees will die in urban areas of Texas also as a result of the 2011 drought. http://usat.ly/OSstp0t.
6. A 1.3-acre urban farm called Eighth Day Farm in Holland Town Center Michigan has been created in the middle of a shopping mall car park. The community can learn about farming, where food comes from & help in the farm as well as buy produce grown without chemicals or pesticides. This is a great idea & will help cut down the Urban Heat Island Effect as well. http://bit.ly/MIlKYt
7. Two tree species considered extinct on two occasions have been rediscovered in, “highly threatened fragments of dry forest in coastal Tanzania. One of the trees, Erythrina schliebenii, belongs to the genus of ‘coral trees,’ which have spectacular red flowers & viciously spiny trunks. The other tree, Karomia gigas, was only known from a single specimen cut down a few years after it was first discovered in coastal Kenya in 1977.” http://bit.ly/RaVUON
8. In an excellent move by the 2012 IUCN World Conservation Congress, a ‘Red List’ has been adopted by for whole ecosystems, instead of just for threatened species. Dr Emily Nicholson of the ARC Centre of Excellence for Environmental Decisions & University of Melbourne’s School of Botany said of the change, “We’re hoping that by establishing sensible global rules for assessing the status and resilience of whole ecosystems we can better protect both them & the individual species they contain.” http://bit.ly/TztaVq
There are a number of pretty verge gardens along Newtington Road Stanmore.
Project WOW – WALKING ON WATER – a collaboration between Marrickville West Primary School, Marrickville Council & the local community in the Riverside Crescent sub-catchment area. Learn about the relationship between how we live, the water cycle, the greater environment & the Cooks River. It should be an inspiring & fun event. Everyone welcome. 
Showing the basin from the top with part of the swale in the foreground
On a steaming hot day last October we went to see the recently completed Johnston Street Bioretention Basin at Earlwood & go for a walk around Illoura Reserve.
The bioretention basin was much larger & more interesting than I expected. The bush at this location was also a surprise being quite different than other areas of Wolli Creek that I have walked. The trees were gorgeous. Towering Red Gums & Turpentine trees lead into the bush & the dreaded Privet was blooming so the air smelt nice.
We went back again today just to see how much the plants in the basin had grown after all this rain we had. It was as expected, lush & green. What wasn’t expected was all the work done by the volunteers of the Wolli Creek Preservation Society. Signs say they are regenerating the bush around the basin. They had opened up a pathway that allowed us to walk right around the basin & up to the Red Gums. It is so nice being in bushland. That it is so close to Marrickville LGA makes us very lucky in my opinion.
Red Gum - there are many great trees in this location
I had not heard of swales & bioretention basins until after starting SoT, so here is a brief rundown of what they do & some stats about this particular basin. A bioretention basin is constructed to manage & clean stormwater before it enters creeks or rivers. Stormwater enters our waterways at a terrific pace. This can erode the bank in places, but also erode the bottom of the watercourse. Stormwater also delivers an enormous amount of pollution to our waterways – nitrogen, phosphorus, heavy metals & fine sediments. All these have a detrimental effect the water quality of our rivers & creeks.
A bioretention basin is really a scooped out landscaped area of land that can be big or small. They generally contain 3 layers: course sand or pea gravel at the bottom, another layer of sand in the middle & sandy loam at the top.
The idea is that stormwater from our streets is directed to the bioretention basin where it literally percolates through these levels. This not only slows the stormwater, but it also cleans it of oils & other substances that comes off our roads. The cleaned water is either allowed to seep naturally into the ground to make its way to the river, or channeled via a pipe or pipes at the lowest layer as it is in this case.
Finally the surface of the basin is planted with native grasses & small shrubs. The plants need to be able to tolerate water as well as periods where the basin is dry. Swales work on the same principle, but rather than a shape of a basin they look similar to a rocky creek bed. The Johnston Street Bioretention Basin also includes a long wide swale running downhill beside the basin. There is a large pipe that directs water from the basin to the bottom of the swale.
The Johnston Street Bioretention Basin, built by Sydney Metropolitan Catchment Management Authority, is expected to remove approximately 2,353 kg of sediment & 13kg of nitrogen annually before it enters Wolli Creek, which flows into the Cooks River & on to Botany Bay. Their sign says that the system is designed to remove 100% of gross pollutants, 79% total suspended solids, 57% total phosphorus & 30% total nitrogen. It’s beautiful & a terrific boon for the environment. It’s also well worth a visit.
I made a short video of the Johnston Street Bioretention Basin & Illoura Reserve here – http://bit.ly/uPLiQX
Showing the swale & the path to Illoura Reserve which is just around the bend.
Raingardens slow water down, spread it out & then soak it into the ground. Hard surfaces speed up rainwater, concentrate it into a smaller area & take it to drains & then to wherever the drains go. In our case, it is mostly the Cooks River.
“A rain garden is a beautiful landscape feature you can put in your yard at home to collect rainwater runoff from your rooftop, your downspouts, driveway, any hard surface. And the plants & soil in the rain garden will filter out any pollutants found in that runoff & slow it & divert it before it goes in the storm drains.” They can be big or small.
Because of recent research by researchers at the University of NSW, we now know for sure what everyone suspected; that the Cooks River is a hotbed of pollutants. Interesting that fishing is increasing along the river when it would be dubious any fish caught is safe to eat. Unfortunately, most of the pollutants (oil, metals, pharmaceuticals, pesticides & other contaminants) come from stormwater that flows directly into the river. Stormwater even as far away as Newtown is in the Cooks River catchment area.
Marrickville Council designed & are in the process of implementing quite detailed stormwater management across the municipality to reduce pollutants entering the Cooks River. Some accessible examples are the swales in Steel Park & at Thornlie Street Marrickville South & raingardens in Wallace & Hill Streets, also in Marrickville South.
I have just learnt of a community driven effort in Seattle to curb pollution from stormwater runoff into Puget Sound. Residents plan to build 12,000 rain gardens over the next 5-years to prevent approximately 160 million gallons of stormwater pollutants entering Puget Sound each year. It is estimated that 40,000 metric tons of oil & grease enter Puget Sound every year & that 75% of all the toxins found in the Sound comes from stormwater runoff. Therefore, 12,000 raingardens should have a significant & positive impact on the water quality of Puget Sound & this benefits everyone, including the environment.
I think it would be quite easy to set up a similar program in Marrickville LGA, as well as the other Council areas that surround the Cooks River. If we started in our neighbourhood first, perhaps the other communities would be inspired & do the same. I think most people care about the health of the river. The great thing about raingardens is that once you build them, they essentially look after themselves.
Raingardens can also help street trees by diverting stormwater into the ground rather than down the drain.
This news item video explains succinctly how raingardens work, their benefits & of the resident campaign in Seattle. “There are many misconceptions about rain gardens. People wonder if they’ll cause flooding or if they’ll become mosquito breeding grounds, or if they’ll be fussy to maintain. But according to the rain garden experts, these are all myths. Probably the biggest myth is that you can’t use these systems or bioretention areas, rain gardens, on poor soils, soils that don’t drain well. And, actually, you know, we’ve applied & installed, you know, designed and installed bioretention systems on poor soils. And they work pretty well. Very well, actually.” – http://htl.li/7UjE3
The following are short videos of swales & raingardens built in Marrickville South. They are all quite different from each other & all enhance the landscape. They probably look even nicer as the plants would have grown more since these videos were taken.
Raingargen: Thornley Street Swale Marrickville South– http://bit.ly/uhFMYa Raingarden: Hill Street Marrickville South – http://bit.ly/vWlgsX Raingarden: Wallace Street Marrickville South – http://bit.ly/u9NNKy Raingardens, Swales & a Saltwater Wetland – Steele Park Marrickville South http://bit.ly/trc9yS
This is one type of raingarden. It is at the bottom of Hill Street Marrickville South & was built by Marrickville Council. Raingardens can be made to look like an ordinary garden with flowers & small shrubs & be of any size.
I saw this clever idea in Marrickville recently. These milk crates prevent the under-road pipe from becoming blocked with rubbish & leaf litter. This photo is of both sides of the same street.
New verge gardens along Mansion Street Marrickville South - a massive improvement to the streetscape
Marrickville Council has recently replaced the concrete footpath & created verge gardens along Mansion Street Marrickville South. I think they look terrific & greatly improve the streetscape. The street trees now have an opportunity to collect sufficient water when it rains & the gardens themselves should reduce stormwater runoff. There are no problems for pedestrians as there are wide pathways from the roadside to the footpath placed at regular intervals.
Considering that Marrickville Council spends in excess of $2-million every year just on mowing grass verges, I think verge gardens like this would be a far better use of our rates. Imagine what $2-million could do each year if it were put into planting street trees & landscaping our streets & parks. It wouldn’t take too long to significantly green up our landscape.
Research has shown that the greener the environment is, the happier & healthier people tend to be. Verge gardens are also beneficial for the environment. They help collect stormwater & pollution from passing traffic & if planted with wildlife-friendly plants, could also provide a food source for our urban wildlife.
Red Flowering gums along a series of verge gardens in Dulwich Hill
We know a good-looking street tree increases the property value of those near it, so it’s only logical that verge gardens & a better-looking streetscape would also improve property values. Green really does equal money when it comes to real estate, especially in high-density areas like the Inner West.
Of course there are streets in Marrickville LGA that do not have room for verge gardens or where they would be impractical, but many could have them. If verge gardens are put into the right places, they should not impede pedestrians or people leaving vehicles. The size of the verge gardens I have seen across Marrickville LGA mean that people pushing prams or shopping trolleys can do so without difficulty.
On the newish verge gardens in Livingstone Road Marrickville, Council has put a concrete path from the kerb to footpath opposite the front gate of all the houses facilitating unobstructed movement from car to house. This has been repeated in all the other verge gardens I have seen. Where multiple verge gardens have been created along a street, there is a pedestrian pathway to the footpath every few metres big enough for a wheelchair, pram or trolley. Council also don’t put plants on the kerb-side of the garden so that people don’t have to exit the passenger-side of the car into shrubbery that could cut their legs or cause them to fall.
My experience of Marrickville Council is that they are highly vigilant when it comes to safety so I can’t imagine them putting in a verge garden where it would cause people problems.
If Council were not spending all their time mowing grass verges, they could be managing the verge gardens instead. Apparently, once they are grown, verge gardens look after themselves & only need a bit of occasional weeding. There is always room for other plants so if property owners wanted to add other plants, they could. They just need to be safe plants for passing pedestrians, children & dogs – so no cacti or other plants that could cause injury, nothing that could cause difficulty for passengers leaving cars & no high-growing plants that could reduce visibility for drivers.
I know this is a contentious issue in the community. I’ve heard arguments against verge gardens that residents should not have to look after the verges, therefore grass verges must continue. My personal opinion is that verge gardens have much in the way of benefit & there is no reason why Council cannot continue to look after these areas. Some people say they like grass verges & I appreciate that. I don’t dislike grass, but I much prefer plants & flowers.
The reality is the climate is changing & as a society, we must make changes that will help lower the urban heat island effect or we will be condemning ourselves to be living in an oven. Grass verges are less effective at cooling through evaporation than plants & trees. A dried out grass verge can take on the qualities of hard surfaces, not absorbing rainwater well. Grass requires a lot of water & maintenance to keep looking good & does nothing to help with biodiversity.
These verge gardens at the Arlington Oval intersection in Dulwich Hill are stunning
View of Sydney from Sydney Park. Note the masses of trees & some Grevillea flowers
About 3 kms from Sydney’s CBD is a glorious emerald jewel called Sydney Park. If you live in the Inner West & own a dog you probably go there often because it is leash-free & offers an incredible amount of room for dogs to run themselves into happy exhaustion. There are even water bowls for dogs to have a pit-stop drink. I knew of Sydney Park’s existence, though I had no idea just how wonderful this park is. My impression over the years was garnered by what I
What I thought Sydney Park was about
could see as I drove along Sydney Park Road in St Peters – a lot of trees near the road, the old brickworks buildings & an enormous grass hill that I didn’t feel like climbing. Then I read an article in the Inner West Courier in 2009 about the killing of a black swan by a dog. Black swan……in Sydney? This enormously sad news item & the subsequent letters from the community was the prompt I needed to finally visit.
That first visit in 2010 is something I will not forget. We stood at the bottom of the park at the Harber Street entrance & surveyed an enormous park with multiple lakes, masses of normal-shaped large trees, patches of woodland & birds everywhere. We were hooked. How had this wonderful place been unknown to us for so many years? If you haven’t been, you must go at least once. I doubt it will be your last visit.
Reflection in the lower lake
Okay there are hills, but most are easily walked. Many people run up them. Wide bitumen footpaths meander through the park. If a hill seems too much for today you can easily head in another direction. The bulk of the park is wheelchair accessible though better if you have someone who can help you up those hills if needed. Prams are a cinch. There is an ‘all-abilities’ playground, accessible toilets & a kiosk, though I haven’t seen these yet.
The 44-hectares of Sydney Park is less than 20-years-old & was built on a former clay extraction & waste disposal site. It is a prime example of how industrial & landfill land can be turned into something beautiful. It was created by the City of Sydney Council who continue to manage it. They not only have created something that is beautiful & entirely useful for the current population, but everything they are doing is creating something for our children’s children & beyond. I don’t know how many Fig trees the City of Sydney Council have planted, but I’d guess at least 200 trees. I’ll have to find out. The Figs are planted reasonably close to each other to create a continuous canopy when grown & to provide shade. They are all young, but in 2-3 decades time, these Fig trees are going to provide phenomenal beauty. Just imagine how lovely this park will look in 100-years time.
Sydney Park has tree precincts. There is the Palm area, the Grevillea woodland, the Tea tree & Callistemon woodland, the Eucalypt woodland, the Casuarinas woodland, the Acacia woodland & so on. We have not seen all the park as yet so there is bound to be more woodland areas. Trees within the park are used to great effect to screen neighbouring factories & surrounding roads. There is no philosophy of maintaining sightlines into this park. Sydney Park is an oasis & provides refuge from busy city living. As much as possible, the noise of busy Princes Highway & surrounding main roads has been kept out, both visually & audibly.
Wattle blooming on an island in one of the lakes
Not only is it a place of beauty, but Sydney Park also functions as a stormwater collection & filtration site. Stormwater from surrounding suburbs comes to a large holding pool where it is filtered & sent on to the first of 5 fairly large lakes. From there it is filtered into the next lake & so on, until it finally filters through the ground into the watertable. The lakes provide 5-star habitat for a wide range of water birds, including migrating birds & Spoonbills.
There are birds everywhere in Sydney Park & they are both wary & curious of people which means you can have a good look at them, but not touch. City of Sydney Council has almost completed fencing the lakes to prevent another dog attack. Wooden poles attached to the cyclone fencing have made the fences look beautiful & a part of the landscape as well as being functional. This is just one example of how artistic, but functional design has been used in Sydney Park. Nothing here is ordinary in my opinion. Everything has been done with beauty in mind & to provide food & habitat to urban wildlife.
There are a number of swales that take stormwater from the park itself into the lakes. We last visited while it was raining & it was easy to see the design that had been implemented to capture runoff down the hills. Much had been directed into woodland & garden areas & the remainder channeled to meet up with bio-swales that took the water to the lakes. To prevent soil erosion, great long snakes of coir encased in rope were laid around garden beds or in front of vulnerable trees. Some of the pathways are permeable.
Kite flying is easy in Sydney Park
While there are areas of lawn for informal ball games, City of Sydney Council have not created yet another park that is essentially paths & lawn surrounded by trees around the periphery & a few along pathways. They have recognized that people want & need shade & desire areas to sit where they can be in the shade. There is not a Crepe myrtle to be seen. They have planted a range of bird-attracting trees & shrubs making this park useful to urban wildlife & there are many areas where it is difficult for people to enter allowing wildlife to have safe habitat.
Much of what has been done in Sydney Park could also be done along the Cooks River. If it were, it’s likely that a greater range of water birds would live along the river. Poles have even been sunk upright into one of the lakes to allow birds to perch as well as making an artistic statement for humans. Trees have side branches offering other places to perch. Few plants are ornamental only. While there are grasses around the lakes, grasses are not the main feature of any planting. Even groundcover is of the type that produces food for small birds. There is loads of colour from flowering trees & shrubs & this will change seasonally. The ground is healthy as there were a range of gorgeous mushrooms & toadstools growing after the rain.
I am in love with Sydney Park. It would have been expensive for City of Sydney Council to create, but this is money well spent & the park is going to only get better as it matures.
There are other features, such as a memorial woodland, that I will post about later. Sydney Park is a prototype of a people-friendly, dog-friendly, wildlife-friendly green space that is not ordinary in any sense & that will only improve as the decades pass. City of Sydney Council have probably won awards for Sydney Park. If they haven’t as yet, then they should. They deserve it.
I have posted a short YouTube video – Birds at Sydney Park Wetlands & will upload more videos of various aspects of this park later – http://www.youtube.com/watch?v=JsHvuGPBjk4
Poles for birds & art in the newest lake. The new fencing can be seen on the right
Yesterday evening we went down to Steele Park in Marrickville South to have a look at how the new swale is going & it’s going well. The new trees have survived, as have many of the plants closer to the river. Those
8 new trees in this garden & a section of great exercise equipment on the left
near the beginning of the swale close to Illawarra Road have not done so well. Having participated in planting these I’d say that 80% planted on the small incline have died. This area is much drier than the other areas.
The saltwater swale is wet & the plants here are also growing well. I still think it looks fantastic & as the plants establish & get stronger it should only improve. In 2-3 years it will be even better. Let’s hope this kind of work & the likes of Cup & Saucer Creek Wetland happen for all the stormwater catchment areas along the Cooks River.
Steele Park
The place is also alive with the sounds of frogs. You can’t get much better than the sounds of frogs at dusk.
I think there has been more planting further along where the planted section meets the grassed area of Steele Park near the playground. Still further along are two mounds where 8 young trees have been planted in one & 4 in another. I was happy to see new trees, especially as they were not Casuarinas. Unfortunately 1 tree has died.
I have only one query & that is why bird-feeding plants & shrubs are not planted along this section of the Cooks River. I haven’t seen bird-feeding plants & shrubs anywhere along Marrickville’s part of the Cooks River, except for some plants in Tempe Reserve. I could be wrong, but my husband hasn’t seen any either. Maybe a Banksia or two, but no Grevilleas or other flowering plants that provides food
There is an acre of Grevilleas at Sydney Park
for birds & flying-foxes. I don’t understand why. Maybe it’s because these plants cost more than grasses or maybe Council doesn’t want them there because they are not indigenous to the area.
We planted 4 Grevilleas & it is astounding how much wildlife comes to feed from these every day. Many species of native birds come taking it in turns, though it is not unusual to see 2 species eating nectar together. Both big & small birds eat from the Grevilleas. Often I am unaware that birds are inside a Grevillea shrub until they come bursting out if I walk too close. Native bees collect nectar as well & at night lone flying-foxes quietly graze until every flower has given up its nectar. I find this particularly special to watch & feel pleased that 4 plants can feed so much urban wildlife.
There is plenty of room for bird-feeding plants & shrubs in most areas of Marrickville LGA, but particularly in the parks & along the Cooks River. To me it is quite strange to have so few sources of food along the Cooks River. The area should be supporting an abundance of wildlife. Instead, the non-waterbirds come to the river areas to sleep, but leave during the day to search for food.
I made a 1.45minute YouTube of the swale at – http://www.youtube.com/watch?v=jz5Sh8gx-Cc
One of several garden areas in Steele Park showing 3 new trees. There is plenty of room for some bird-attracting plants & shrubs
Happy concrete
I have mentioned recently that Portland Oregon in the US has for a while been my number one favourite with all things environmental in an urban environment. If it can be done & improves the livability of the environment, they do it. If it extends the life of a street tree, they do it. If it improves stormwater management, they do it. They also have what appears to be large community interest & involvement with a thriving community of volunteers across many programs that better the urban environment. Portland shows the rest of us what can be done.
The latest that I have discovered is depaving. There is a push coming from the community to remove unnecessary concrete in urban environments for the following reasons –
- It’s ugly & not seen as conducive to creating livable cities.
- It’s bad for stormwater management. Hard surfaces increase stormwater, over-burden drains & carry large amounts of ground pollution to rivers, lakes & oceans.
- Impervious surfaces prevent much of the rainwater seeping into & refilling the groundwater table.
- Impervious surfaces increase the Heat Island Effect making our environment hotter than it needs to be resulting in increased power usage just to cool our buildings.
- Concreted surfaces have destroyed habitat & made whole areas unsuitable for urban wildlife.
- In some cases these kind of surfaces have disconnected people from the natural world. Some people see concrete as ‘clean’ & fallen leaves as ‘dirty.’ This creates a cycle where more & more trees in gardens & along streets are seen as pests & either removed or vandalized. Once the overall canopy is lessened, the Heat Island Effect grows, power use also grows, but what doesn’t grow is urban wildlife who has fewer places of habitat & food supplies.
Thankfully street trees were planted last year in this vast area of new asphalt in Camperdown. The photo doesn't show it, but the pavement is at least 5 metres across with plenty of room for gardens
Paul Sheehan wrote the following for the Sydney Morning Herald in July 2009 - “You, reader, live in a primitive city. In a hundred years from now, the society we are building will look back & marvel at how little we really understood about the world we have constructed for ourselves.
We are stewing in our own juices.
Last Wednesday, a night of driving rain, I attended a seminar where more than 100 professionals, a standing room-only crowd, had gathered to learn about practical, cheap, achievable ways of stopping Sydney’s pot from simmering. These were not wide-eyed utopians. In purely parochial terms, the heating of our biggest cities is even bigger than the global warming debate. Because the rise in temperature is mostly & demonstrably caused by outdated thinking.
The story starts on Observatory Hill, at the southern end of the Harbour Bridge, where weather records have been kept daily since 1860. What the observatory has recorded is a rise in the average temperature at the centre of Sydney from 20.5 degrees to 22 degrees. As Sydney grows, Sydney slowly heats.
At last Wednesday’s seminar we learnt why – 27% of the surface of the metropolitan area is covered by bitumen, the black tar which soaks & retains heat & thus changes the city’s climate.
Nearly all the rainwater run-off on this 27% of the city is lost to productive use, flowing into Sydney Harbour because it is designed that way. The city’s rooftops also gather heat. Roads & pavements maximise the waste of arable land. Tree-planting is stunted for legal reasons. Topsoil is “scalped” by roadworks. The increasing use of air-conditioners is creating more energy. More heat begets more heat.”
There is much more to this article, including the work Landscape Architect Micheal Mobbs & his neighbours are doing to green & cool the residential streets of Chippendale – http://www.smh.com.au/environment/climate-change/we-are-stewing-in-our-own-oven-20090726-dxew.html
I wrote about Micheal Mobbs & his green verges here – http://savingourtrees.wordpress.com/2010/10/24/verge-gardens-in-chippendale/
Great use of stormwater, but not very efficient
People & local Councils have paved whatever they could since the late 70s. It was a movement of convenience as concrete is easier to drive on, easier to walk along & easier to clean with a hose. The main beneficiaries were people with a disability who need flat surfaces to get around & parents with prams.
I believe we need to continue to provide safe & easy access for everyone & there is much need for improvement in this area. Just last month I watched a man in a wheelchair who was forced to travel along the road next to Petersham Town Hall with the cars because there were no wheelchair ramps on the high kerbs at all 4 corners of the cross road. There must be many such areas like this that make wheelchair travel dangerous & difficult.
Leaving aside wheelchair & pram accessible footpaths & kerbs, many government authorities overseas think that concrete worship has gone too far &, because of the above negative effects, are rethinking their concreting practices of the past.
Most car parks do not need to have concrete or asphalt/bitumen. They can easily be compacted permeable surfaces allowing stormwater to travel into the ground to the water table rather than into 100-plus-year-old drains. Permeable surfaces actually need less maintenance than do impervious bitumen surfaces & therefore are cheaper in the long run. Appropriate trees can be planted within the parking spaces improving the visual outlook & also helping with stormwater & pollution uptake.
Footpaths do not need to be wall to kerb, except in shopping strips where a greater use of the footpath space is required or where the space between building & kerb is unusually narrow.
This was a very popular landscaping idea in the 1990's. Cement pavers with pebbles or mondo grass in between allowed walking, but let the water drain away.
Marrickville Council is adept in building bio-swales & rain gardens. There is no reason why a small rain garden or two cannot be built within a car park if there is a reasonable flow of water from nearby buildings & from the lie of the land when it rains.
I suspect these ideas will be dismissed in most areas of Australia as ‘too greenie’ because of the convenience of paved surfaces. However, in a few years depaving will be the norm because of the worldwide push to restore groundwater, lessen the Heat Island Effect, restore habitat & make cities more livable.
Although many governments are stalling any real action on climate change, some overseas already depave, create green space & plant more trees in public spaces in cities because they know what is coming. It is like a slow culture change. Once we get used to these changes back to softer infrastructure, we will cope with the bigger changes of gravel lanes & fewer paved surfaces.
If we can create a balance where people who require flat surfaces for mobility can have this, but remove unnecessary hard surfaces & green up, we will have a much cooler, prettier, more environmentally friendly & wildlife habitable environment to live in. It doesn’t take much to create a huge improvement on many levels.
Here is a 4-minute film where the Portland community removed 278.7 sq metres (3,000 sq feet) of asphalt to create a community space with a perennial food forest. http://www.streetfilms.org/depaving-day/
Many hundreds of cars use this car park to busy shops in Croydon 7 days a week. Cars are sheltered from the sun under Ornamental Pear trees, there are garden spaces where the trees are, red gravel allows the water to pass into the ground. There are no tyre troughs or dips & it is easy to walk on. Your car is cool when you return from shopping & it is visually pretty making the shopping area look more inviting. (Ignore the imprisoned tree. It's far to late for it now)
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