Climate-proofing
Jakarta
Arlene Nathania Chryssilla ; The
writer is currently researching water spatial planning for her doctoral
degree at the Resource Efficiency in Architecture and Planning (REAP)
Department of HafenCity Universität, Hamburg
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JAKARTA
POST, 29 Maret 2014
Global
climate change is threatening the delta city of Jakarta. More than two thirds
of the world’s largest cities are vulnerable to rising sea levels and
unpredictable extreme rainfall patterns (Connecting Delta Cities, n.d.).
Jakarta
itself has been sinking partly below the mean sea level, with accelerated
subsidence rates due to excessive long-term groundwater abstraction, as the
fresh surface water currently available only covers 30 percent of water
demand, as confirmed by the Public Works Ministry in 2011. Thus, it is no
wonder that the city is always inundated perennially, though there is neither
significant heavy rainfall nor any notable height in sea water levels during
the spring-tide cycles.
We must
accept the fact that Jakarta’s hydrological balance has degraded over past
decades due to the city’s rapid urbanization being unsupported by adequate
capacity in water infrastructure. Moreover, Jakarta has experienced
uncontrolled urban land-use mismanagement, where many open, public,
waterscape and green areas have been sacrificed to become commercial land
plots.
A higher
amount of builtup areas with decreasing green areas will accelerate rainwater
runoffs, lessen water evaporation, and reduce rainwater infiltration to
groundwater (Hoyer et al., 2011). The city’s lack of urban green areas tends
to degrade Jakarta’s hydrology system, as well as trigger more severe urban
water-related issues and heat-island effects in the city (Chryssilla, 2014).
Developed
countries currently adopt a general green space standard of 20 square meters
per capita (Sukopp et al., 1995; Wang, 2009). Therefore, to accommodate
Jakarta’s approximately 9.5 million inhabitants, the city should supposedly
provide at least 19,000 hectares (ha) of green space, or 28.7 percent of city
(Chryssilla, 2014). Given the city’s current scarcity of land and its culture
of commercialized urban development, which perceives that available open
spaces are worth too much to be utilized merely as landscapes, where to find
these 19,000 ha?
The city
government is in the middle of its regular attempt to solve Jakarta’s
water-related problems, which included perennial floods, freshwater
shortages, groundwater-related land subsidence and water pollution. However,
to hypothetically revitalize this huge megacity requires a massive
interdisciplinary approach and long-term commitment.
Jakarta’s
ongoing flood prevention programs and initiatives are mostly large-scale
centralized solutions that depend on the capacity and funding of the city
government in manifesting action, namely Jakarta’s giant sea walls, the
National Capital Integrated Coastal Development (Dutch Water Sector, 2013) or
multipurpose deep tunnel projects. Jakartans wish for a more sustainable
city, but probably would not be willing to pay the external costs that result
from their own unsustainable habits.
Therefore,
the agenda to revitalize Jakarta into livable city is undeniably a
chicken-egg dilemma. Jakarta actually has the capacity to reduce its
catastrophic floods and land subsidence, by looking into possibilities of
increasing water retention space and green zones. The Jakarta government
continues to explore robust and trial-and-error solutions, without respect to
Jakarta’s existing urban fabric, which has been established over more than
four centuries (Chryssilla, 2014).
To cope
with flooding, the city totally relies on canal systems previously built by
the Dutch (Simamora, 2007). During the colonial period, the Dutch copied
Amsterdam’s urban and water infrastructure in a one-to-one planning
principle, without considering Jakarta’s specific tropical characteristics or
predicting that the city would grow into a megacity. Now it has become
apparent that the Dutch canal systems were not appropriate for the tropical
climate.
Considering
Jakarta’s existing organic urban structures in most areas of the city,
Jakarta could have at least 21,170 ha of pocket land — currently home to
environmentally degraded kampung, slums, as well as unmanaged open green
spaces and water spaces — the locations of which are decentralized, and
dotted throughout the city (Chryssilla, 2014). Having decentralized urban
fabric with different characteristics from one district and another requires
a decentralized approach to spatial solutions.
In
dealing with Jakarta’s urban water-related problems, Jakarta’s urban water
management needs a paradigm shift from a centralized to decentralized
approach, which should be spatially integrated into urban design for the
whole city’s urbanization process. The general theory behind decentralized
water management is to convert threats into opportunities, and waste into
resources, where the objective is to bring the urban cycle closer to a
natural one by applying ad hoc spatial and landscape planning strategies that
are adapted to the specific local basic conditions (Hoyer et al., 2011;
Schuetze & Chelleri, 2013).
For
example, Jakarta actually has abundant rainwater resources provided by its
tropical monsoonal characteristics and annual average precipitation of 1755
millimeters per year (Climatemps, n.d.). If the said 21,170 ha of land could
be revitalized through decentralized urban storm and rainwater management, in
the long term this approach would naturally slow down the city’s stormwater
runoff and retain more rainwater, to encourage more evaporation.
This
would reduce the perennial flood risk, as well as independently provide more
fresh water infiltration to recharge the previously exploited groundwater
basin, which has caused the sinking-land behavior. Additionally, if being
replicated on a city scale, this approach would also generate new urban
learning landscapes in adopting a new urban lifestyle; that is, living with
water.
The
neglected and decentralized 21,170 ha of land would potentially become cityscape
assets, which would maintain the hydrological equilibrium of the city, as
well as enable all of Jakarta’s urban structures to become one urban entity.
Therefore,
I highly encourage any stakeholders who are in charge of developing this
darling city to consider decentralized urban water management as Jakarta’s
main water and spatial planning agenda in the future.
On its
journey to becoming a sustainable and climate-proof city, Jakarta’s
adaptability will always depend on how we strategically and creatively
utilize our available resources and convert the city’s internal and external
threats to opportunities. ●
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