The Roads, Housing and Urban Development Research Center affiliated to the Ministry of Roads and Urban Development has tightened regulations on construction of buildings in Tehran’s earthquake fault zones (a network of interconnected fractures representing the surficial expression of a fault).
The center’s proposals have been sent to the Supreme Council for Urban Planning and Development, and after approval, the Tehran Municipality (TM) will be notified.
As per the new revisions, construction of buildings with more than 12 stories, as well as hospitals and emergency centers in fault zones, is banned, the Persian-language newspaper ‘Iran’ reported.
The measure was taken after the urban planning authorities finally developed fault maps for the capital’s 22 districts.
At a meeting on June 25, attended by head of the research center and deputy minister of roads and urban development Mohammad Shekarchizadeh, head of the Tehran City Council civil committee Eqbal Shakeri, and head of Tehran’s Crisis Management Organization Ahmad Sadeqi, it was announced that separate earthquake fault maps for the city’s 22 districts have been officially approved.
Although work on the development of the maps started in 2008, there were some disagreements on the location of some fault zones, Sadeqi said.
Identification and close examination of fault zones is a continuous process. During the last couple of decades, the length of the Kan and Niavaran fault lines has increased by 4 and 13 km, respectively.
Shekarchizadeh said, “Tehran, Mashhad, Kerman are prone to earthquakes and regions around the fault lines are more vulnerable to damage in the instance of an earthquake, and therefore construction within fault zones should be limited.”
From among 80 sq km of fault zones in Tehran Province, 47 sq km are in Tehran city.
After approval by the authorities, the next step “is retrofitting old structures in the fault zones and restricting new constructions.”
Seismic Vulnerability
The total length of eight fault lines in Tehran Province is 410 km of which, 249 km is in Tehran city. The fault zones cover 6% of the province’s land area, Shekarchizadeh said. In sum, there are 350 fault lines in the country, each over 20 km long.
He hoped that with the approval of fault zone maps, better measures on integrated crisis management would be taken “to make the capital more resistant and safe against earthquake risks.”
Tehran city with a population of over 8 million people is among the world’s top 10 cities that are prone to severe damage if a major earthquake occurs.
The official emphasized the critical need for making buildings resistant against quakes and said figures released by the research center show that currently, 1.1 million people in the huge metropolis live in dilapidated buildings.
There are four major faults around Tehran, including Mosha-Fesham, North Tehran fault and South and North Rey faults and according to experts, Mosha-Fesham and Rey faults are susceptible to a Richter 7+ magnitude.
Iran is one of the most seismically active countries in the world, as it straddles several major fault lines that cover at least 90% of the country. As a result, earthquakes in the country occur often and some have been very destructive, leading to massive loss of life and property.
In the past decade, of the 46,969 quakes of over two Richter registered in the country, 45 were more than 5.5 magnitude.
The 6.6 Richter Bam earthquakes in 2003 was one of the most destructive in the recent history of Iran. It destroyed the historic city of Bam and killed nearly 27,000 people. The Arg-e-Bam, one of the oldest adobe monuments in the world was also destroyed.
