Izmit 1999 Earthquake:

 

Map of northwestern Turkey depicting the fault lines running between the Anatolian Block and the Eurasian Plate and the location of the epicentre of the İzmit earthquake of Aug. 17, 1999. (Encyclopedia Britannica, Inc, n.d.)

            At around 3 am local time on the 17^th of August 1999, northwestern Turkey was struck by an earthquake with a magnitude of 7.4 (Gillies et al., 2001). It occurred on the northernmost strand of the Northern Anatolian fault system with an initial shock that lasted less than a minute. It was then followed by two smaller aftershocks on August 19^th (USGS, 2022). 

The main regions affected by this earthquake were the densely populated cities of Izmit and Adapazari, which are located in the provinces of Kocaeli and Sakarya. This was mainly due to the epicentre being located about 11km southeast of Izmit. These afflicted regions were Turkey’s industrial core, with Istanbul and nearby provinces accounting for approximately one-third of the nation’s total output (Bibbee et al., 2000).

There were many impacts caused by the initial earthquake. Many apartment buildings entirely collapsed, killing a large number of individuals who had been asleep when the earthquake struck. It took five and a half days to control and put out a fire in the Tupras oil refiners, which at the time processed 86% of Turkey’s oil. The fire had threatened to spread to neighbouring industrial facilities. Surface breaks cut into the toe of the fan delta where the town of Degirmendere was located at the western end of the rapture zone. This resulted in a slump, 100m normal to the coastline. Parts of Degimendere slid under water, including a hotel as well as several stores and restaurants. The severity, scope, and loss of life during the first two days were vastly underestimated. (Barka, 1999)

At least 17,118 people were killed, close to 50,000 were wounded, about 600,000 were left homeless, and the damage ranged from 3 to 6.5 billion USD in the provinces of Kocaeli and Sakarya, and Instanbul. (USGS, 2022).

In the past, Turkish builders employed conventional, time-tested construction techniques to reduce damage from earthquakes. However, rapid growth in population in the early 1980s changed this (Gillies et al., 2001) and the earthquake exposed several flaws in urban design and construction methods that had increased the infrastructure and death toll of the disaster:

Large-scale urbanisation had been approved where liquefiable soil was present. Because the majority of the impacted infrastructure was less than twenty years old, the horrific death toll resulting from poor foundation systems – one of the main causes of destruction in Adapazari – is all the more tragic. 

Problems with construction engineering were a significant additional cause of the catastrophe. Most collapsed multi-story buildings had weak ground floor levels due to their use for commercial purposes, with fewer retaining walls and higher ceilings, which led to ground floor collapses. The widespread usage of hollow clay tiles that are not reinforced to build interior and exterior walls had a negative impact on how well the structural frame performed during the earthquake. (Bibbee et al., 2000).

Buildings damaged by the İzmit earthquake in Turkey, 1999 (Encyclopedia Britannica, Inc, n.d.)

The challenges in mounting a prompt and efficient official emergency response to the earthquake may have contributed to the significant loss of human life. This was mostly because it happened at 3 am with many of the emergency response officials among those who were trapped inside the collapsed buildings. As well as this the majority of the emergency response equipment was destroyed or damaged. (Bibbee et al., 2000).

Poor communication and significant damage to the main route linking Istanbul and Ankara lead to further delays in rescue efforts. It was further exacerbated by people blocking other routes when attempting to reach family and friends in the worst-affected areas (Barka, 1999).  Over 600 000 individuals were forced to seek emergency shelter as a result of the earthquake's damage to or destruction of over more than 300 000 dwelling units. The government made the early decision that stronger temporary housing have to be used in place of tents due to the impending cold and wet winter weather. (Bibbee et al., 2000). Private contractors were criticised heavily for their work and for utilising cheap, subpar materials as the majority of the fatalities were caused by the collapse of residential buildings. Although several contractors were criminally charged, relatively few of them were convicted. The public chastised officials for not enforcing building regulations about earthquake-resistant designs. (Tikkanen., 2022).

Video: https://www.youtube.com/watch?v=T0VV_JOmNps

References:

Barka, A., 1999. The 17 August 1999 Izmit earthquake. Science, 285(5435), pp.1858–1859.

Bibbee, A. et al., 2000. Economic effects of the 1999 Turkish earthquakes. OECD Economics Department Working Papers.

Earthquake.usgs.gov. 2022. [online] Available at: <https://earthquake.usgs.gov/earthquakes/eventpage/usp0009d4z/executive> [Accessed 10 September 2022].

Encyclopedia Britannica, Inc, n.d. Map of northwestern Turkey depicting the location of the epicentre of the İzmit earthquake of Aug. 17, 1999.. [image] Available at: <https://www.britannica.com/event/Izmit-earthquake-of-1999> [Accessed 12 September 2022].

Gillies, A., Anderson, D., Mitchell, D., Tinawi, R., Saatcioglu, M., Gardner, N. and Ghoborah, A., 2001. The August 17, 1999, Kocaeli (Turkey) earthquake — lifelines and preparedness. Canadian Journal of Civil Engineering, 28(6), pp.881-890.

Tikkanen., A., 2022. İzmit earthquake of 1999 | Turkey. [online] Encyclopedia Britannica. Available at: <https://www.britannica.com/event/Izmit-earthquake-of-1999> [Accessed 10 September 2022].

U.S Geological Survey, n.d. İzmit earthquake of 1999. [image] Available at: <https://www.britannica.com/event/Izmit-earthquake-of-1999> [Accessed 12 September 2022].