The Impacts of Pollution for New High-Speed Railways: the Case of Noise in Turkey

In recent years, high-speed train operations have been increasing, yet their environmental impact is still not well researched and understood. Evaluation of the impacts of Turkey's new high-speed train lines from the perspectives of noise, vibration and socio-economic issues is important to secure sustainable development in the sector. National and international regulations are important to enable environmentally friendly railway systems to be secured. In this study, national and international regulations for the control of noise from conventional and high-speed train operations are reviewed and used to estimate distances which should not be exceeded for the Turkish high-speed train system. Calculated distances for EU and Turkish systems for noise threshold values of 87 dB (A) pass-by noise (L-pAeq,L-Tp-measured 25 m distance from the centreline of the track and 3.5 m above the rail head), 65, 60 and 55 dB (A) (L-pAeq,L- day; L-pAeq,L- evening and L-pAeq,L- night, the A-weighted average sound level for the specified time periods, at the most affected residential area, 4 +/- 0.2 m above the ground) were 28, 160, 272 and 469 m from the centreline of the track, respectively. These threshold distances were defined as a buffer zone in a railway map of Turkey in ArcGIS v.10.2.1 and merged with the Turkey population map to determine the population numbers which would be subjected to exposure above the threshold limits. Calculations conducted for highly populated cities showed that 2325, 22,839 and 3184 people would be exposed to railway noise exceeding the EU 96/48/EC Directive threshold limit 87 dB (A) for Ankara, Istanbul and Izmir, respectively. When calculations were repeated for the Turkey regulation threshold limits 65, 60 and 55 dB (A), these numbers were 10,767, 19,298, 35,951 for Ankara; 125,033, 210,360, 357,041 for Istanbul and 17,340, 29,026, 49,318 for Izmir, respectively. The data indicate that some noise mitigation is required to protect human health in Turkey and potential mitigation strategies are discussed.