Construction work on Cairo's third metro line has left one district decidedly pockmarked, reports Reem Leila Drilling works for the second phase of Cairo's third metro line caused a 15-metre wide section of Al-Geish Street in the Bab Al-She'riya district of Cairo to collapse on 3 September. Ten buildings, home to 80 families, have been evacuated. The residents are currently housed in armed forces accommodation. Engineer Mustafa Zahran, head of Bab Al-She'riya district, told Al-Ahram Weekly that the families involved would receive compensation at a daily rate of LE1,000, paid by the National Authority for Tunnels (NAT). Zahran estimates the sinkhole that appeared following the collapse is 20 m deep. The crater was immediately filled with water. A team of engineers from NAT has examined the site to determine whether the tunnel and surrounding buildings have been seriously affected or not. The precise reason for the subsidence, says Zahran, remains unclear, though few people doubt that drilling work is a major factor, together with excessive amounts of groundwater that had weakened the subsoil structure. It took three days for NAT to drain the crater and fill the sinkhole with more than 1,000 cubic metres of concrete in an attempt to prevent the collapse, which initially covered an area approximately 30 metres by 20 metres, from spreading. Unfortunately this did not prevent a second, deeper landslide, from occurring on Sunday, at 7:45pm. Cairo Governor Abdel-Azim Wazir has set up a committee, including NAT engineers, to deal with the fall out from the collapse. The committee, says Wazir, will supervise the repair of water, gas and drainage pipes. Utilities, including electricity, water and natural gas, were cut immediately after the landslide but resumed 24 hours later. "Of course the collapse will cause a delay," says NAT head Atta El-Sherbini. "We can't continue working on the metro until this hole is fixed. It is not a minor hiccup, it's a very serious problem and it is far from clear when we will be able to resume drilling." Fortunately, El-Sherbini adds, groundwater was prevented from penetrating already constructed tunnels. NAT issued a statement saying Cairo governorate and the Ministry of Interior were coordinating efforts to secure the area and guarantee the resumption of tunneling as soon as possible. "In addition," says El-Sherbini, "NAT has called in three experts to examine the exact reason for the landfall." The all too evident hole has left local residents worried over the possible consequences of further drilling. El-Sherbini, though, is confident the disaster will not be repeated, pointing out that the Bab Al-She'riya district is a special case since it "floats" above large quantities of groundwater. Residents of Al-Geish Street have yet to take official reassurances to heart. Ask passersby which part of the street is suffering from subsidence and they will tell you brusquely that it is the entire road. "Most of the street is sinking in a big mess," said one man before walking off. Not that he had much walking space. The main square, completely drenched in water and mud, has been closed off. No injuries were caused by the collapse, though seven parked cars slid into the resulting pit. Six cars were retrieved. Mohamed Hashim, owner of the remaining car, says he will file a lawsuit against the tunnel authority and the Cairo governorate for the "losses estimated at LE120,000". The third metro line will extend until Heliopolis, passing by Cairo Fairgrounds, Cairo Stadium and Koliyat Al-Banat. It will cost LE3.3 billion and serve an estimated 250,000 passengers daily, generating annual income of LE3 billion. The line, due to be inaugurated in late 2012, will streamline traffic in the areas it covers. "A good underground metro line is like a new lung. It will decrease traffic on the surface," says El-Sherbini. "As the safest and cheapest method of transportation, the new line is rightfully being touted as one of the most important projects for a generation."