|Al-Ahram Weekly On-line
1 - 7 October 1998
|Published in Cairo by AL-AHRAM established in 1875||Current issue | Previous issue | Site map|
High waters, little danger
The flood, the highest since 1988, raised public fears, especially after opposition newspapers reported that several villages near the Nile banks, as well as river islands, were submerged. But officials insist that, thanks to the dam and the Toshka depression, there is no real danger.
According to official statistics, the flood will continue to increase the volume of water in Lake Nasser by about 750 million cubic metres a day. This means that the volume of water flowing into the lake this week will amount to 24.580 billion cubic metres. At present, the total volume of water inside the lake, with a total capacity of 164 billion cubic metres, amounts to 153.91 billion cubic metres.
Minister of Public Works and Water Resources Mahmoud Abu Zeid announced early this week that the water level is under control. He said that studies had shown that it is unlikely to exceed 181 metres. But if it does, the excess water will be diverted through a spillway to the Toshka depression, which can hold up to 120 billion cubic metres, as well as to two other depressions to the east and west of the lake.
The Toshka spillway is designed to open once the water level in Lake Nasser reaches 178 metres. The ministry has already diverted 560 million cubic metres of water to the Toshka depression and another 240 million cubic metres into the Mediterranean.
To guard against possible danger, the ministry announced a state of emergency in Aswan and asked all its affiliate bodies as well as municipal and rural authorities to be on the alert.
According to statements by the ministry, the flood does not pose any danger to the High Dam, urban constructions or ancient monuments.
As for the reported flooded lands, Abu Zeid explained that they were shanty settlements illegally established either on river islands or along the Nile's banks. Those living there had no right to be there anyway, he added.
The annual flood, which occurs in August and September, is caused by rainfall in Ethiopia, which accounts for 85 per cent of the river's water flow.
According to an Ancient Egyptian legend, the flood volume changes every seven years, resulting in consecutive periods of seven lean and seven fat years. But these periods of scarcity and abundance may extend to as many as 10 to 20 years.
Prior to the construction of the High Dam, the flood posed a serious danger to villages and cultivated lands located near the river banks. Approximately 32 billion cubic metres of water were discharged into the Mediterranean and wasted, while the amount stored behind the old Aswan dam did not exceed five billion cubic metres.
"The construction of the High Dam spared Egypt the risk of flooding," said Abdel-Fattah El-Fiqi, head of the irrigation department at Ain Shams University's Faculty of Engineering. "The force of the flood would have been five times higher than the current figures. The dam has provided a water reservoir to be used during the lean years."
This year's flood, however, came at a time when the water level in Lake Nasser was already high, according to Yehia Abdel-Aziz, head of the irrigation department at the Ministry of Public Works and Water Resources. The ministry's primary option, he said, was to divert the excess water to the Toshka depression, rather than discharge it into the Mediterranean. "We first channeled the excess water to Toshka, but when the water level rose even higher, we had to discharge it into the sea to maintain the safety of the dam," Abdel-Aziz said.
Although ministry officials believe that the water level is unlikely to reach hazardous levels, they add that the ministry has plans to face any unexpected contingency. "The water level can be predicted 10 or even 11 days ahead, which gives us ample time to make plans for the incoming water," Abdel-Aziz said. "We work around the clock to monitor rainfall and the water level in collaboration with the countries where the river resources are located."
According to Mustafa Mohamed Suleiman, professor of irrigation at Ain Shams University's Faculty of Engineering, the discharge of water provides an opportunity for purifying the river's course of pollutants and salinity. "But since the construction of the High Dam, the amount of discharged water has dropped and it is not enough to clear the river's course of ever-increasing pollution," he said.
Questions have also been raised about how the water diverted to Toshka will be used and whether the nature of the soil there will not make it seep into neighbouring Libya. "There is no doubt that proper planning is lacking," said geologist Ahmed Farouk. "To make proper use of the water drained in Toshka, geological studies should have been made on the nature of the soil there." He said predictions are never that accurate when it comes to natural phenomena. "The government should have taken proper precautions in case of any unexpected increase in the water level," Farouk said.
But Ahmed Maher, Minister Abu Zeid's adviser and former head of the irrigation department, refuted the allegations. "Toshka was designed primarily to protect the High Dam and not to store water," he said. "Nor was it designed to make sustainable development in the area, because its water income is not stable."
Maher added that the water drained in the depression will not be lost since it will be added to the volume of subterranean water in the area. He also said that studies had shown that the water cannot seep into Libya as some people claim.
Photos: Sherif Sonbol