Facing Water Challenges in Istanbul

From WaterWiki.net

Jump to: navigation, search

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.


Focus Areas

Geographic Scope




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


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


8758 Rating: 2.1/5 (57 votes cast)