Penultimately, we’re gunna need a boat.

The truth is, the vast majority of Humans live ‘off’ the land now anyway. Today, most humans are either already living in cities or moving to live in cities, where weather and the environment are generally considered to be inconveniences.

In fact, just about everybody considers weather to be an inconvenience; particularly those who have to work in it, or profit from it. Farmers are increasingly finding nature to be most uncooperative in the production of vital grains and vegetables. Rain either doesn’t fall, or falls at the wrong times. Unseasonable heat waves, harsh winds, cold snaps, insect and mouse plagues; what has always been a risky business has grown distinctly riskier in recent years.

It seems quite bizarre that the creation of so essential and indispensable a commodity as food, required by so very many, should be left to such a small handful of individuals and the vagaries of nature.

Far from being supported and nurtured by the natural environment, farmers have been at odds with nature for centuries. From using simple irrigation systems thousands of years ago to overcome the unreliability of rains, to artificial fertilisers and pesticides and air conditioned tractors, and crops and even livestock raised completely indoors, the march away from the natural environment has been ongoing and relentless.

So why not take the ultimate step?

Since most of us already live ‘off’ the land, moving our cities onto the seas would not be as big a step as you might think.

Firstly, consider cost. How much would a quarter acre block be worth, on the water front at Bondi? With concrete currently retailing at about $200. a cubic metre, a quarter acre (1000 sq. metre) of concrete would cost about $20,000 in materials alone. A pontoon 3 metres deep (more than enough to float an average home) would only cost about $50,000 in materials.

For a 1000 sq. metre block with absolute water frontage, on all four sides.

Of course, there’s no reason to build such an ugly edifice. My home will be 3 stories; I above and 2 below sea level. Can you imagine looking out your window at a reef (underwater veranda) full of fish?

In other words, instead of building on a pontoon, the house is the pontoon, thus eliminating the cost of a ‘building block’ entirely.

This is a much more modest proposal than other recent suggestions, such as the ‘Lilypad‘ concept, or the “Seasteading” institute; both of which focus on building cities and/or societies entire, rather than the traditional ‘organic’ approach of building cities, one house at a time, as suggested here.

The costs could conceivably be even lower than you might think. Seacrete or biocrete forms when a small electric current flows through a metal grid submerged in sea water. Calcium and salt deposits form around the grid, creating a material quite similar to concrete.

Although current studies tend to indicate the strength of this material is rather low, perhaps we could start with a traditional concrete frame, and encourage seacrete to grow around it, so buildings would continue to grow stronger year after year, rather than degrade, as our current buildings do.

This would justify the existing trend of buildings continuing to inflate in price, even as they are degrading structurally.

The arguments in favour of a floating arcology are almost beyond counting.

Complete immunity from earthquakes and floods.

Little or no money spent on roads and guttering; certainly no road maintenance.

A totally enclosed, climate controlled environment.

No cockroaches, or mosquitoes, or ants or mice or any uninvited pests; meaning no chemical deterrents required.

Each home could have sections devoted to hydroponic and sterile earth gardens, giving families a measure of independence and offering some defence against catastrophic system failure -such as the world is currently undergoing.

A community of fully enclosed, interlocking homes could be not only be self sufficient and sustainable, but could also have viable exports of surplus or waste products.

Energy would be supplied by wind, waves and solar. Houses and communities would be buoyed up with compressed air, requiring technology not much more advanced than a push bike pump; operated by wave action. Surplus compressed air could drive generators on windless days. Temperature control could be achieved simply by adjusting air flow through various depths of sea water; apple orchards and cool season crops located in the lower levels. These levels would also supply an ideal environment for computers, and any industry benefiting from strict temperature control and a sterile environment.

Fear of pandemics would be a thing of the past. Floating communities could be the most physically and biologically secure environments on the planet.

Protection from severe wave action would be provided by a ring of floating pontoons, in much the same way as reefs shelter coral atolls. These pontoons would supply compressed air power to the communities, as well as roosts for sea birds. Guano could again be a valuable export to drylanders, along with night soil and seaweed compost; to replace some of the soils the drylanders so carelessly lose to the oceans every day.

In the lagoons formed inside the protective ring, fish farms. With intensive breeding programs, we could actually start giving back to nature with restocking programs, instead of continually raping and diminishing her.

All bio waste would be directed to methane digesters; the bio gas used to power boats; if anyone ever wanted to visit the old world.

In a post peak oil world, manufacturing will no longer be dominated by countries with cheap labour (and consequent low living standards). The most practical place for manufacturing will be at sites with reliable cheap renewable energy. As manufacturing becomes more and more automated, energy will replace labour as the major component of price.

I don’t know about you, but when I think of the world’s most beautiful places, my rating is almost invariably in inverse proportion to human impact; apart from a few examples of -generally ancient- architectural grandeur. We now have the capacity to reduce our impact on the landscape to virtually zero, while our impact on the seascape would be minimal.

Even a city the size of Sydney would not be much more than a flyspeck, in the middle of the Pacific ocean.

One could reasonably hope that in such an enclosed, climate controlled community, materialism and consumerism would not be required. Emphasis would be on having zero or beneficial impact on the outside environment; by pumping up cold water and nutrients from the depths, algae would be encouraged, to increase Co2 conversion and possibly even affect the weather.

And who should pioneer this last frontier?

Well, Baby Boomers, of course. For a start, most of us have houses we can sell, to buy into an arcology.

We are beyond breeding age, to stabilise population growth.

And the message is getting increasingly stronger, that we simply are no longer required.

As for the support an aging population needs, there are more than enough impoverished children in the world, who I’m sure would jump at the chance of a good home, in return for a few household chores…