Isn’t it simply too late to restore natural systems?
We could think in terms of gradually, but systematically, replacing engineering structures with
natural systems that were previously replaced by engineering structures. In some places, like
California, serious consideration is being given to ‘unplugging’ certain dams and letting rivers return
to original flows. This is not just romanticism. Increasingly, people are realizing that a return to
natural conditions would be more economical and efficient from a whole systems perspective. Other
alternatives to privatizing and/or piping water include design concepts like the ‘chain-of-ponds’, a
water restoration approach for drought-ridden Australia. This concept, developed by Australian
farmer Peter Andrews, was based on the study of ecological systems that preceded the advent of
Western agriculture [Box 46].
48
By creating a series of ponds off the main river, flooding, loss of
topsoil and other problems caused by interventions in the natural flow of rivers have been reversed.
The approach creates synergistic effects in the environment that pipelines do not, such as purifying
water, increasing biodiversity and habitat, and reducing floods. The system works as a Living Machine,
but on a landscape scale. It may only be suitable for certain landscapes, however. An earlier advocate
of using natural systems was Ian McCarg, who looked at solutions for a wide range of conditions.
Back in the 1960s, he developed landscape design concepts based on the biophysical characteristics of
regions. He looked to the original landscape and ecosystem functions for inspiration in his seminal
Design with Nature
.
49
How would this apply to urban bioregional planning in built-up areas?
The advantage of the urban context is that, unlike natural areas, cities could increase overall carrying
capacity over pre-development conditions. This would require
neither
the kind of large-scale, socially-
disruptive re-development associated with post-war planning
nor
the abdication of planning to
incremental approvals of (least bad) market-driven development. After all, the ownership of buildings
is constantly being transferred, and buildings constantly upgraded and re-sold. So eco-retrofitting
can occur as opportunities arise. Buildings, their façades and roofs, and the spaces between them
can be ‘churned’ through an eco-retrofitting programme as they become ready for refurbishment,
in a virtuous circle. But again, sustainable design solutions will not become mainstream until the
political ramifications of current accounting methods are made transparent. Putting alternatives on
an equal footing would not be difficult, but it is seldom done.
The capital budgets of maintaining large
buildings or universities are enormous and expensive refurbishments are periodically undertaken.
Such ‘deferred maintenance’ of unsustainable development is not worth the long-term cost, but we
discount the future. Due partly to current accounting methods, however, decision-makers seldom
consider investments that would reduce maintenance costs by using natural systems. In a sustainability
analysis, we should at least put the status quo system and the proposed alternatives on the same page.
Instead of the ‘sunk cost’ in vast industrial infrastructure, we would compare the relative costs of the
215
Bioregional Planning
status quo and eco-logical design alternatives
as if
neither were yet in place, and consider what each
would cost to maintain in the long run.
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