After writing post last night, went on a world tour using google earth, measuring the diameters of random cities around the world. First problem is that it’s not that easy to identify the boundaries of a central hub to a town or city, or even the actual boundaries of the cities. Most do not expand radially they extend in a linear manner. The line of expansion is following the path of a river, canal, railway, highway, mountain range or coast line. So measured across corners of noticeably built up areas, or regions bounded by ring roads.
A lot of cities are on coastlines, located on peninsulas, and other outcrops of land, or they are in sheltered bays and follow the coast around the bay. Some of these outcrops are only around 1 km wide, so expansion is limited.
Anycase generally found building clusters fitting cells 1 km to 2 km diameter. Where hubs not identifiable cells 5km to 15km would enclose the regions, with larger developments 20 km to 30 km. The largest developments being 30 km to 50 km.
Also read an article today which indicated bricks are transported to regions upto 500 miles [805 km] away. Which highlights the issue of linear development. Resources are distributed from one region to another via some transportation channel. Linear development then occurs along this channel, a transportation hub exists at the origin of the resource. When the resource is expended the destinations are left relatively inefficient.
It also highlights the problems associated with resolving urban sprawl. The central hub of a city is seldom a centre of production and distribution: it is a centre where resources are directed to not distributed from. For example power is not produced at the city centre, water is not distributed from the city centre, sewage is not processed at the city centre, few if any utilities are supplied from the city centre. Food is not produced in the city centre. Resources are not mined in the city centre.
City centres are typically centres of art and culture, government and business administration, and retail. For the most part the big cities could be burnt to the ground, and there would be no real loss to the surrounding communities. Since there is no essential function in these centres: sure the politicians and company CEO’s think they are important, but in the main they spend most of their time debating unnecessary change, change for change’s sake. There are other systems in place carrying out the essential and necessary management functions.
Now if have a floating space colony beyond Pluto, there would be no transport channels from each resource required to sustain the colony. Spaceships could arrive from anywhere, to one or more docking ports on the space station. On the ground it would appear that roads have to enter a city from a specific direction: though this is not entirely necessary. Ancient fortress towns, with moats and draw bridges only had one port of entry. Whilst modern cities construct ring roads in attempts to reduce traffic congestion: which usually doesn’t work.
May be the approach is wrong, instead of trying to ease traffic congestion, maybe we should deliberately introduce bottlenecks. I say again that urban sprawl is not caused by the car, but by large facilities demanding large populations to support their existence. Urban sprawl is not about the size of the built up area, it’s about the dependence of the built up area on a common centre. In South Australia for example the people of rural town of Gawler should not need to visit Adelaide on a regular basis, and similarly the people of Tea Tree Gully should likewise not need to visit Adelaide on a regular basis. More importantly the people of the satellite city of Elizabeth, absolutely should not need to go any where near Adelaide: is it a city or a shopping precinct?
It is economy of scale which is shaping our cities. The idea that big is better. As I mentioned in earlier posts the largest industrial blocks of land are for car industry. But why do we need a single facility that can assemble 100,000 vehicles each and every year? With a population of 1.5 million, it would take around 15 years to supply the state with a vehicle, then what? Think big! Ok! A national population of around 20 million, it would take 200 years: then what?
Reality is that large production facilities have short lifespans. Their purpose is to satisfy demand rapidly, once the demand is satisfied the facility becomes redundant. Smaller facilities are required to maintain and repair, and small facilities are required for more customised product.
Now if one production facility with around 2000 people, can produce 100,000 vehicles each year, and a vehicle is the first private space most people acquire, it would seem that such facility could provide housing to the world faster than onsite construction. For a future world population of 10 billion would need 100,000 facilities, to achieve full supply in one year. Alternatively sticking with the 1000 industrial city-states, 100km diameter, with populations of 10 million each, then surmise that every million people needs one facility, therefore 10 facilities per city, and world total of 10,000. But once demand is satisfied, the facilities reduce in size and increase in number. But then again maybe a large number of smaller facilities located in local communities is better able to supply the world population in the first place.
Resources need to be distributed to different places. If resources keep going to the same places, then people have no choice but to migrate to those places, which in turn increases the demand for resources in those places. But such increased demand typically increases the energy resources required to get other resources from increasingly distant places to the common centres. Centres which are only common because they were drawing in resources in the first place.
So there is a need to improve the distribution of resources to people wherever they maybe. This is not contrary to a mobile population: a mobile population can be anywhere. The problem we have is people are moving to common centres: this isn’t mobility, or a mobile population, this is just people changing where they are intending to stay permanently. Both goods and people are being concentrated in location. A diversity of locations is better for the environment. Diversity is typically best for most things.
Anti Competition laws protect competition, enable monopolies, and destroy diversity. The problem with fossil fuels is lack of diversity. Alternative energy supplies will be just as problematic if they hold monopoly, if we have a lack of diversity. The objective should not be to find an alternative, it should be to encourage diversity.
A starting point to protect diversity, is to protect locality.
This is a city, and this is a rural town, and between them should be at least a 10 km wide green belt which is protected and not permitted to contain buildings. Or if buildings are permitted then constraints are placed on those building in terms of function, height, plan area, and distance between. For example buildings a minimum distance of 1 km apart, and only used for art and culture, or agriculture.
Anycase most of our industrial and commercial facilities along with housing have had their day. We need a new city. If the facilities were mobile, then the city could easily reform, change the layout not just the facilities. But it cannot and we have to waste resources maintaining it. Or do we? At some point we have to recognise that continuation is the problem and change to doing something else. It is not a simple matter of knocking buildings down and redeveloping the sites: it is nations, entire countries and continents which need to change their whole built environment.
Small modular units are flexible and adaptable, and replaceable.