Sydney, Melbourne and Brisbane together account for half of the population, all with a fraction of the gross densities of cities such as Amsterdam, Berlin and London. Except for the innermost municipality areas (boroughs) of the two former – accounting for 1 in 25-30 of the inhabitants of either city – with 80, 40, 9 (net), 50, 60 and 70 inhabitants per hectare gross respectively.
Four challenges faced nationwide in both urban, suburban and rural areas are: Average homes sizes being the second largest in the world at almost 200 sq metres. The number of cars per capita being the third highest in the world after the US and New Zealand. The proportion of parents driving their children to school. And a majority of employers offering free car parking for their employees – sometimes in highly accessible locations and town centres.
This article sets out seven priorities that could maybe halve Sydney and Brisbane energy use and carbon emissions within a few decades – the former with two or three city centres, Sydney Harbour, Parramatta and the just announced South West Creek, the former and latter 50 km apart.
1_ Low carbon row housing town centres
New housing suburbs are somewhat old fashioned – with their endless two or three car household bungalows – a twenty century solution for the twentieth first century. When maybe half of households would be happy in semi dense walkable neighbourhoods. With two or three storey terraced, row or town houses or two or three storey semi detached (twin) houses. Especially if located within long walking distance of walkable apartment neighbourhoods with ground floor mixed uses – for shopping, services, leisure, crafts, co-working – and a train or tram station at their centres.
Present day Sydney is particularly relevant, as the model for new neighbourhoods within a kilometre or a mile radius of a new train or tram station already exists in the inner western suburbs of Sydney. With its mixture of dwelling types and sizes – apartments, terraced bungalows and town houses – small businesses, parks, craft, retail, civic and commercial services and activities.
Constructing apartments within half a mile radius or 200 ha gross area of a station, row housing within the next half a mile radius or 600 ha, and semi detached and detaches houses within the next half a mile radius or 1100 ha further out. The former two should generate enough footfall to support mixed use ground floors throughout the mixed use apartment neighbourhoods.
At 50 and 25 units per hectare gross (including roads), the two former could accommodate up to 5k and 8k dwellings respectively. With 30k inhabitants within a mile radius or 8 sq km of a station. Or 44k inhabitants within 1.5 mile radius or 19 sq km. If half the land is residential, one sixth parks, one sixth civic and one sixth commercial. With car parking either underground or as curbside perpendicular and longitudinal residential parking along side streets. Saving energy and land – reducing emission, distances, travel times and commuting – easing daily life, mobility and logistics.
The above example contrast somewhat with the newly announced town of South West Creek, near the planned Sydney western airport, where a similar amount of inhabitants – 30k – will be housed in an area twice the size of the above example – 15 sq km rather than 8 sq km.
As for accommodating another 4.5 million inhabitants or 2 million households by the middle of the century in Sydney. If half were to live in apartments or row housing, and half of them in mostly new greenfield areas. There would be a need for 16 new train or tram station towns within one mile radius of apartments and row houses. Together these 16 towns can accommodate half a million households or one million inhabitants within long walking distance or a mile radius of the station. Providing the 200 ha mixed use apartment neighbourhoods with enough inhabitants to support a vibrant social, civic and commercial scene and life.
2_ Multi-use ground floors and parks
Nurseries, services, craft and light industries could increasingly be located on the ground floor of apartment buildings throughout near station areas of the two cities. Including workshops, studios, co-work places and pre-school nurseries in apartment blocks adjacent to parks. Nurseries sharing the use of a communal garden within the block or the adjacent local park during the day. In new near station areas, a mixed use local or larger park could be provided for every 8 or 10 surrounding blocks in medium and higher density areas. Large enough to be used by a large nursery during the day, a sports court for adults in the evening, and all local inhabitants young and old alike at the weekend.
3_ Low carbon homes, commercial and civic buildings
Most of existing homes of the two cities are lower carbon, so turning them into zero carbon should be possible for the great majority of homes. Electronically controlling solar gain and natural ventilation by more shading during the summer months and more glazing during the winter months goes a long way. As for new apartments, they should all be able to rely on convection cooling during the summer months by including adequately sized and located vertical ventilation shafts.
Most new and some existing commercial and civic buildings have a great potential for being mostly cooled and ventilated by convection. As for existing buildings, controlling solar gain during the summer and winter months goes a long way in converting them to lower carbon. Introducing a requirement – similar to that in Switzerland – for all windows to have external sun shading should be implemented within a year or two.
4_ Low carbon e-mobility
Daily commuting to work, nursery, for shopping, education or leisure is complicated in both almost entirely suburban cities. Further complicated by fact that the population of Sydney is estimated to double to 9 million – on par with present day London – and Brisbane to a third of Sydney's size within half a century.
A dozen major high streets and a dozen selected shopping, service, retail and leisure centres as well as all Westfield's in both cities could be more readily accessible by e-bikes. Equipped with e-bike charging points, e-cargo shared bikes, and encircled by e-bike and bike priority routes within a two mile radius. Maybe increasing five to ten fold the proportion of e-biking and cycling customers and visitors within a decade.
In both cities e-cycling could further change the status-quo, with segregated e-bike lanes. With priority at junctions, against one-way streets, with e-bike parking and bikes on off-peak and non-radial transit routes. Including innovative provisions within a two to three mile radius of the three to four dozen top frequency/connected train stations in both cities.
5_ Low car traffic city and town centres
Restricting car traffic within the inner cities could evolve travel behaviour, limiting the car to predominantly suburban to suburban trips. For example by introducing congestion charging similar to that in Singapore and Scandinavia, evolving from the present per motorway mileage. Further, neither city are on an island like Manhattan and both cities are built on solid rock making tunnelling and bypassing traffic possible. In Brisbane there is already a 2 x 5 km triangular shaped motorway network surrounding the centre. Potentially allowing most traffic to bypass the centre if the majority of the inner city's inhabitants, commuters and visitors alike chose to travel there without their cars.
In Sydney, a similar 4 x 8 km rectangular network is partly planned, partly being built – but strongly resisted by the central municipality. Maybe because some neighbourhoods will be left with more traffic or because some inhabitants will be left with expensive tolls. Why the municipality is unwilling to shut side streets to retain traffic levels at present or even lower levels is unclear. Particularly as the majority of their inhabitants will probably benefit, but only if bypassing the centre is financially cheaper than entering it. Congestion charging external drivers more for crossing the motorway ring than staying on it or outside it is possible. But charging inner city inhabitants only when crossing the motorway ring – as in Singapore and Scandinavia, but unlike in London.
Combining congestion charging with increased restrictions on non-residential and residential car parking; shutting side streets outside peak hours and at weekend; rewarding, e-bike, e-cars and e-vans financially; and introducing widespread car sharing are four supplementary possibilities. The latter offering a valuable alternative for car ownership in one person households or a second car in two person households. Both within and a few miles outside the motorway rings around the inner cities – to promote an alternative to public transport for both for radial on non-radial travel and commuting.
The four supplementary possibilities should also be introduced in a few dozen higher density areas and town centres throughout the outer suburbs of the two cities. To better shelter mixed use commercial and residential urban neighbourhoods. Improving quality of life for inhabitants. And make it more attractive to live, grow up and retire there for families, couples as well as singles – young and old.
6_ Commuting and transit rethink
Reducing car commuting proportion from three quarters to a half by increasing e-biking and public transport would reduce emissions the most. The latter would be easier with more bus lanes, bus stops a third of a mile apart, increased priority of non-cars at junctions, easier identified routes, improved information at bus stops and inside buses, service guarantees and refunds.
Both cities can also learn from Brisbane's network of underground bus tunnels; The Hague's and San Francisco's underground tram lines; Copenhagen's automatic circular metro; Stockholm and Paris' orbital tram lines; Up to 24 trains per hour on London Crossrail, Thameslink, Paris' RER C and 30 tph on RER A; Berlin S-bahn's 10 and 20 min frequency; Madrid's multitude of train and metro tunnels through solid rocks deep into the suburbs; 55m long and 300 passenger trams in Budapest.
Generally, maybe as much as one quarter of new transit investments are too low capacity, one quarter is years or decades ahead of demand, one quarter would benefit from a different alignment, and only one quarter is meeting and balancing demand and supply nicely. The three former are sometimes possible to avoid, sometimes not – depending on political, financial and forecasting possibilities and constraints.
Some possibilities that maybe deserve further study in Sydney are: Bus tunnels under Neutral Bay and Surrey Hills; A rail loop connecting UNSW and Randwick to Bondi Junction and Green Square; Extending the western tramline north and northeast towards Chatswood, Frenchs Forest and Dee Why and south towards Wolli Creek to connect it to six radial train lines, from two only at present. Increasing the number of trains through the centre from 16+18/20+16 trains per peak hours long the three present lines to 24+24/24+24+24 with an addition line would increase capacity by two thirds.
7_ Renewable energy and construction
Net carbon free electricity is possible by 2050 or 2060 if solar and wind is expanded to replace coal as the main source of electric according to some. Whether this goal includes converting cars, vans, lorries and buses to electricity is unclear at present. Similarly, there is little mention of whether to replace natural gas use with solar or wind for heating water, pools and buildings.
Reducing the carbon footprint of the construction sector is another necessity – amounting to one quarter of carbon emission nationwide at present – if global warming is to be reduced to less than 1.5C. Use of concrete and steel is carbon intensive, and its use increases proportionally with the height of a building. Very high density urban and very low density suburban areas are also more carbon intensive, the former with its multitude of partly underground services, and the latter with its high proportion of meters of roads per households.
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