At 4,180 miles, the river Nile is the longest river in the world and lies at the heart of the cradle of civilization. Today, it is the main source of water for people of the lower Nile basin countries of Egypt, Sudan and Ethiopia…
A case in point is Egypt, which currently depends on the river Nile for 97 percent of its water. Because of the growth in demand for drinking water, outpacing the Nile supplied water, the government is encouraging the construction of desalination plants to top up supplies of water.
Economic and agricultural development in the countries along its banks has increased the demand for its water, while hydro projects upstream, are leading to disputes between Nile states over water extraction. By 2050, around a billion people will live in the countries through which the Nile and its tributaries flow. That alone will put enormous stress on the water supply. Climate change and increasing human activity alongside the course of Africa’s longest river threatens this life-sustaining force.
This feature looks at the impact of climate change and construction of a mega dam on the river Nile.
Climate change impact
El Niño and La Niña weather events, occurring in the Pacific Ocean, affect the weather around the world and in particular, have a big impact on the annual rainfall patterns in the Ethiopian Highlands, the source of 80 percent of the Nile’s water. Global warming, the result of millions of metric tons of greenhouse emissions being released into the atmosphere each year, is likely to increase the intensity and the duration of the El Nino/La Nina cycles.
A new report by Professor Elfatih Eltahir and post-doc Mohamed Siam, of the Massachusetts Institute of Technology (MIT), predicts that as a result of climate change, the water levels of the river Nile will become increasingly unpredictable. They foresee that a year of devastating floods could be followed in the next by a severe drought. Indeed, this may already be happening. Drought conditions in the Nile basin in 2015 have been attributed to an intense El Niño event. The following year, La Nina is thought to have been responsible for intense flooding in many countries. The MIT report suggests that in the future, there are likely to be fewer normal Nile flow years.
For centuries, the annual Nile floods carried silt from the Ethiopian mountains downstream to fertilize the fields along the riverbanks of the Nile Delta and Egypt’s breadbasket. However, the area is just one meter above sea level and sinking at between four millimeters and eight millimeters a year, due to a combination of seismic activity, compacting soil and the lack of sufficient new sediment reaching the delta. At the same time, due to climate change, the sea level is rising at three millimeters per year, allowing seawater to slowly seep into the delta’s aquifer. By the end of the century, 60 percent of the Nile delta region could be salt saturated and as much of 20 percent could be under water.