Facing Water Challenges in Istanbul
From WaterWiki.net
- Synopsis
In coping with the challenges and demands of a megalopolis suffering the effects of an unplanned urban boom, officials are relying on significant infrastructure investment, public information campaigns and better enforcement of city planning regulations.
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Background and Significance
Istanbul, located in north-western Turkey, has a population of over 12 million (Turkish Statistical Institute, 2007). Home to 17.6% of the country’s population, it is the largest city in Turkey and one of the 25 largest in the world. Uniquely, by virtue of its situation straddling the Bosphorus strait, it has a presence on both the European and Asian continents.
- Climate Change - Anticipating Problems
Although the data do not indicate a clear declining trend in rainfall in Istanbul and its surroundings, extreme events – especially droughts – seem more pronounced than in the past. In 2006, the measured rainfall of 66.7 mm was the record low for the previous 50 years, a period during which the average was 257.2 mm per year. Furthermore, the water level in reservoirs serving the city was just 45% in 2004, and plummeted to around 25% in 2007 and 2008 (ISKI, 2008). Officials at Istanbul Water and Sewerage Administration (ISKI), using the Intergovernmental Panel on Climate Control scenario of a 2°C temperature increase by 2030, have estimated the likely decrease in total reservoir capacity due to higher evaporation rates. Their calculations revealed that the water potential of the city might drop by as much as 14% over the next two decades. This projection, coupled with water demand scenarios, indicates that the onset of a water crisis is likely by 2030. In response, remedial actions are being taken, ranging from water saving campaigns to projects transferring water to Istanbul from as much as 150 km away.
- Monitoring, Water Transfer and Expanded Treatment Facilities
Water to meet the needs of metropolitan Istanbul comes from the Marmara and Melen basins, whose combined water potential (including artificial storage) amounts to about 3.34 billion m3. Groundwater resources are limited; their annual potential is around 0.175 billion m3. To protect this precious resource, regulations prohibit the drilling and operation of wells without obtaining a permit. Depending on quality, some groundwater resources are mainly used for drinking water supply while others meet water needs in industry. However, uncontrolled settlement and over-abstraction have diminished groundwater levels and led to saltwater intrusion in coastal areas. The decline in the water table due to unsustainable abstraction ranges from 30 metres to as much as 150 metres in some areas. Both surface and groundwater quality is monitored through 51 observation stations scattered throughout the two basins.
In 2007, the amount of water resources in use was
1.42 billion m3. This means 40% of the water potential is
being exploited, on average. However, geographic and
seasonal disparities in the distribution of water resources,
coupled in recent years with severe drought, have
necessitated interbasin water transfer projects to provide
more water where needed in Istanbul. For example, the
Melen Project Phase I, which became operational in
December 2007, supplies an additional 0.27 billion m3 of
water per year. With the full realization of similar
projects, some 66% of the potential water resources
would be made available for use.
As of 2007, ISKI operated six large water treatment plants
and a number of smaller units. ISKI’s master plan for
water, which included construction of treatment plants,
was based on projections of population growth and an
accompanying increase in water demand. However, the
projections proved to be overestimates, and the
treatment plants currently operate at 61% of capacity.
Although the existing plants can keep up with
population growth in the near future, new facilities are
being planned and constructed to assure the long term
needs of the Istanbul metropolitan area.
Some 0.2 billion m3 of treated wastewater is discharged
from Istanbul into the sea every day. To make more
efficient use of water resources and cope with periods of
drought, water recycling plants are being planned, with
the first one expected to be operational in 2009.
- Insitutional Mechanisms for Water and Sanitation Service Provision
In its long history, Istanbul has served as the capital of many great civilizations. During the time of the Ottoman Empire (ca 1299–1922), water structures dating from Roman times were improved and extended, and aqueducts, reservoirs, wells and cisterns were added to improve freshwater supply to a growing population. After 1923, when the Republic of Turkey was founded, the Istanbul Water Administration (ISI) took over responsibility for managing the city’s water resources.
Intensive internal migration to Istanbul resulted in a
population boom and unplanned urbanization in the
shape of shanty towns on the outskirts of the city.
These conditions, which made it all but impossible
for the ISI to meet everyone’s water and sanitation
needs in a city astride two continents, necessitated the
establishment of institutions with the financial and
human resources needed to cope with the challenges.
Today, ISKI and the General Directorate of State
Hydraulic Works (DSI) are the main institutions
responsible for developing water resources for Istanbul.
DSI was founded in 1954 and is responsible for planning,
managing and developing all water resources in Turkey.
ISKI, founded in 1982, is charged with setting up
and maintaining water and sanitation infrastructure,
managing surface and groundwater resources for
domestic and industrial use, collecting, treating and
disposing of wastewater, and protecting water resources
from pollution. It is also responsible for river
rehabilitation within greater Istanbul.
Although investment by both institutions has helped
address water-related problems in Istanbul, a lack of
coordination among various agencies dealing with water
management in the city, combined with a complex and
fragmented division of authority that makes it difficult
to enforce regulations, is a critical issue that stands in the
way of effective water governance.
The Experience: Challenges and Solutions
- Service coverage and expansion of the metropolitan
area In 1900, Istanbul was one of the few cities in the world with a population of 1 million, and it took almost 70 years for this number to double. However, with the onset of east to west migration in the mid-1970s, the population more than quadrupled in just 20 years’ time, reaching some 6.6 million in 1990. Since then the population has again almost doubled, making Istanbul one of the world’s 25 most populous cities. Most of its estimated 12 million people live on the European side. In 2004, the borders of the city were extended significantly, increasing ISKI’s service area from 1,972 km2 to 5,342 km2 (or 6,500 km2 if one includes the basin areas outside the provincial borders). These figures make clear the sheer magnitude of the challenge involved in providing basic water and sanitation services to the city.
However, thanks to significant investment, which
especially gained momentum from the mid-1990s to
total US$3.6 billion between 1994 and 2004, the water
supply and sanitation infrastructure has improved
considerably. Water storage capacity, for example,
increased from 0.59 billion m3 in 1994 to 1.17 billion m3
in 2005. In addition, ISKI formulated the Water Master
Plan in 2004 to address long term needs to 2040 by
taking into account population estimates, water demand,
water resources availability, water purification and
sewerage work, etc. The plan includes new large water
supply projects, such as pipelines to bring water from the
Asian side to the European side (e.g. the Melen Project),
to meet projected demand (Altınbilek, 2006).
- River improvement and environmental protection
River improvement projects are necessary to ameliorate the quality of urban life and protect residents from socio-economic hazards associated with flooding. They become even more critical in densely populated settlements like Istanbul, where the rate of infrastructure expansion cannot keep up with the increase in demand stemming from continued internal migration. Such unplanned growth also creates serious problems with enforcement of urban planning rules and building codes.
Many projects have aimed to restore the quality of rivers
that had turned into open sewers, especially during the
1990s. Unfortunately, due to a lack of financial resources,
only 313 km of the 1,825 km of streams within the
boundaries of the Istanbul Metropolitan Municipality
have so far been improved.
The best example of environmental restoration in
Istanbul concerns the Golden Horn. Once the pearl of
Istanbul, the Golden Horn became an environmental
disaster after its surroundings turned into an unplanned
industrial zone housing docks, factories and warehouses.
By 1985 around 700 industrial plants and 2,000
workshops had been opened along the Golden Horn.
Hundreds of thousands of tonnes of waste were dumped
directly into the waterway every year, gradually
destroying all aquatic life. Finally, in the late 1980s, the
Istanbul Metropolitan Municipality Government and
ISKI joined forces to save the Golden Horn by
constructing wastewater collectors, tunnels, pumping
stations, wastewater treatment plants and related
utilities, thus revitalizing the environment of the area.
The Golden Horn Environmental Protection Project,
with a total cost of some US$650 million, received first
prize in 2002 from the World Association of the Major
Metropolises (Altınbilek, 2006).
- Unplanned urbanization
Unplanned urbanization through illegal construction is a serious problem in Istanbul. It entails risks of socio-economic losses, especially if structures are built in flood prone areas like those near river embankments. Such settlements are either not connected or illegally connected to water supply and sanitation infrastructure. Illegal connections can lead to water pollution, environmental degradation, and discontinuity in service provision due to resultant malfunctioning of local infrastructure. The combination of these factors often leads, in turn, to health problems. As part of an effort to prevent illegal urban development in protected water basins, ISKI uses remote sensing technology to run a basin information system for periodic monitoring of structural changes in its service area. The system has allowed municipal authorities to detect illegal construction in a relatively short time and to intervene accordingly.
In summary, Istanbul is one of the great metropolitan areas of
the world, but it is suffering from unplanned and
accelerating urbanization. Seasonal and geographic
variations in water availability, coupled with pollution
and wasteful water use, put the resource under everincreasing
pressure. The authorities are working seriously
to address quality issues and improve the coverage of
water supply and sanitation services. Nevertheless, there
is still some progress to be made in terms of service
provision, public awareness raising, implementation of
laws and regulations, and the much needed political will
to move forward.
Results and Impact
Lessons for Replication
Testimonies and Stakeholder Perceptions
References
See also
Altınbilek, D. 2006. Water Management in Istanbul. Water Resources Development, Vol. 22, No. 2, pp. 241–53. Istanbul Water and Sewerage Administration (ISKI). 2008. Barajların Doluluk Oranları [Water level in reservoirs]. http://www.iski.gov.tr/web/statik.aspx?KID=1000717 (Accessed December 2008.)
Istanbul Water and Sewerage Administration (ISKI)/General Directorate of
State Hydraulic Works (DSI). 2008. Istanbul Case Study Report. (Draft.)
Turkish Statistical Institute. 2007. 2007 Nüfus Sayımı Sonuçları [2007 census
results]. http://www.scribd.com/doc/1250825/TUK-Adrese-Dayal-Nufus-
Kayt-Sistemi-2007-Nufus-Saym-Sonuclar (Accessed October 2008.)
External Resources
The United Nations World Water Development Report 3
