install telephone landlines and are now committed to cellphone networks as a more
feasible telecommunications strategy.
The concept of the sustainable city is one expression of new goal setting and
practices. An absolute definition of sustainability remains elusive. Use of the term
can raise lengthy debate about theory, practice, and measurement. Sustainability
resists precision, but the concept’s diverse interpretations promote experimentation
and innovation. Given population and urbanization trends, megacities can be leaders
in sustainability technologies. Combined concentration of population and consumption within cities gives them enormous leverage to lower per capita infrastructure
costs, enable materials reuse, and boost efficiencies of energy use (Glaeser 2011).
8.3.1 Green Infrastructure for Sustainability
Communities are exploring practical integrations of built and natural systems based
on the concept of green infrastructure (Benedict and McMahon 2006; Rouse and
Bunster-Ossa 2013). An ecological infrastructure incorporates all the natural, seminatural, and artificial networks of multifunctional ecological systems within, around,
and between urban areas at all spatial scales (Tzoulas et al. 2007). As a strategy,
green infrastructure can upgrade parks and open space into a coherent planning
scheme having differently scaled landscape units with functional linkages
(Sandström 2002). Rather than imposing built forms that function for a singular
outcome, such as rainwater removal or reduced combustion emissions, a systems
approach considers both primary objectives and externalities, making use of ecological networks and flows as much as possible (Meadows 2008).
Green infrastructure promotes design for sustainability. Leaders in the professional disciplines of architecture, landscape architecture, engineering, and allied
professions strive to reduce (perhaps even eliminate) the negative environmental
impacts of built structures within urban landscape systems. In such projects, every
bit of land within a development is scrutinized for potential sustainability function.
Systems thinking is applied so that energy and materials are not simply removed
from a site but are retained and reused in novel ways.
In both sustainability design and green infrastructure, ecological process is
harnessed to reduce impacts, although the physical expression may bear little
resemblance to an endemic pristine landscape. For instance, reductions of off-site
stormwater flow may be achieved using a combination of rooftop vegetation,
pervious paving, roadside bioswales, rain gardens, a series of connected retention
ponds, and underwater detention facilities, with the entire system serving to slow
water flow and increase soil infiltration.
Innovations are developing rapidly. Nature-based solutions are being devised and
implemented. Some are achieved directly on the ground plane. Others entail engineering strategies so that large buildings or complexes (schools, libraries, and city
halls) contain networked features such as green roofs, living walls, and water reuse
systems. Gray infrastructure systems can be retrofitted with ecological elements such
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K. L. Wolf
feasible telecommunications strategy.
The concept of the sustainable city is one expression of new goal setting and
practices. An absolute definition of sustainability remains elusive. Use of the term
can raise lengthy debate about theory, practice, and measurement. Sustainability
resists precision, but the concept’s diverse interpretations promote experimentation
and innovation. Given population and urbanization trends, megacities can be leaders
in sustainability technologies. Combined concentration of population and consumption within cities gives them enormous leverage to lower per capita infrastructure
costs, enable materials reuse, and boost efficiencies of energy use (Glaeser 2011).
8.3.1 Green Infrastructure for Sustainability
Communities are exploring practical integrations of built and natural systems based
on the concept of green infrastructure (Benedict and McMahon 2006; Rouse and
Bunster-Ossa 2013). An ecological infrastructure incorporates all the natural, seminatural, and artificial networks of multifunctional ecological systems within, around,
and between urban areas at all spatial scales (Tzoulas et al. 2007). As a strategy,
green infrastructure can upgrade parks and open space into a coherent planning
scheme having differently scaled landscape units with functional linkages
(Sandström 2002). Rather than imposing built forms that function for a singular
outcome, such as rainwater removal or reduced combustion emissions, a systems
approach considers both primary objectives and externalities, making use of ecological networks and flows as much as possible (Meadows 2008).
Green infrastructure promotes design for sustainability. Leaders in the professional disciplines of architecture, landscape architecture, engineering, and allied
professions strive to reduce (perhaps even eliminate) the negative environmental
impacts of built structures within urban landscape systems. In such projects, every
bit of land within a development is scrutinized for potential sustainability function.
Systems thinking is applied so that energy and materials are not simply removed
from a site but are retained and reused in novel ways.
In both sustainability design and green infrastructure, ecological process is
harnessed to reduce impacts, although the physical expression may bear little
resemblance to an endemic pristine landscape. For instance, reductions of off-site
stormwater flow may be achieved using a combination of rooftop vegetation,
pervious paving, roadside bioswales, rain gardens, a series of connected retention
ponds, and underwater detention facilities, with the entire system serving to slow
water flow and increase soil infiltration.
Innovations are developing rapidly. Nature-based solutions are being devised and
implemented. Some are achieved directly on the ground plane. Others entail engineering strategies so that large buildings or complexes (schools, libraries, and city
halls) contain networked features such as green roofs, living walls, and water reuse
systems. Gray infrastructure systems can be retrofitted with ecological elements such
138
K. L. Wolf