Geo Ethiopia Alternative Water Source

SSS

Ethiopia - Alternative Water Sources

Before the dam in Ethiopia is built, other possible options will need to be evaluated. Where else within the region could Ethiopians take water from? How would the Egyptians cope at the time the dam was filling up? These are all the sort of things which need to be taken into consideration before a decision can be reached.

One way of extracting water from the ground is to dig into any rock which is an aquifer. This simply means that it holds water inside it. If these rocks are tapped correctly, the water inside them can be steadily drained out, leaving a source which is almost always virus, and pollution free. This is because it has been locked away in the rock, remote from any forms of contamination. One drawback of water that has remained within a rock for some time is that minerals from the surroundings can eventually dissolve into it. Luckily, the levels of minerals, particularly in the sandy aquifers of West Africa, are quite low consistently.

Groundwater from deeper marine layers, however-such as occurs in parts of North Africa, Mozambique, Ethiopia, and South Africa-may have a high content of dissolved salts. This water is useless for drinking, and this is why wells are normally very shallow. Less water is gained from shallow wells, but it is salt free. In moist, tropical countries water from certain rocks will generally contain only small amounts of dissolved minerals. These rocks are the Precambrian rocks, rocks that date to the earliest geological period and are found very deep down. Comparatively, in the volcanic areas of East Africa groundwater may have so high a content of fluorine as to make it unfit for human consumption.

In most countries, the aquifers are found in groups, at roughly the same level. The depth of this level and how far underground it is can very a lot. In the Sahara a rock bed called the Continental Intercalary series, which dates from the early Cretaceous Period and which includes the...