In response to the post
and discussion on this subject with Professor Faisal Hossain of Tennessee Technological University, he assigned a student, Wondmagegn Yigzaw, to explore this subject. Below, with permission, is a report of what was found
Summary of readings from materials on the web by Wondmagegn Yigzaw and Fasial Hossain
1. Lake Chad
Lake Chad is a shallow lake found in the Sahara Region of Africa. It borders four countries; Chad, Cameroon, Niger, and Nigeria. It is a source of water for a population of about 20 million.
The lake is believed to have been a result of an inland sea which has shrunk to a lake form due to climate effect over a very long time. It was one of the largest lakes in the world in the early 1900’s. The shrinkage of the lake has begun in 1960’s due to the use of water by the surrounding population. By this time the size of the Lake was 26,000 Km2. According to the United Nations its size has shrunk by 95% between 1963 and 1998.
The lake is a vital source of water for human, livestock and wildlife community in the surrounding area (Eric et.al, Campbell et.al). Other activities near the lake include Soda-mining, fishing, and farming (Campbell et.al). The Nigerian Southern Chad Irrigation Project (SCIP) is the largest irrigation scheme that was constructed depending on the Lake water. The project was fully commissioned in the year 1979, but it failed to function up to its design after 6 years due to level variation of the river. During this period the contribution of overall irrigation practice was only 5 out of the 30% shrinkage (Coe et.al).
50% of the shrinkage is due to natural climate effects while the remaining 50% is as a result of human interference in the form of irrigation and deforestations (Coe et.al). Between the periods 1953-1979, the contribution of overall irrigation practice was only 5 out of the 30% shrinkage (Coe et.al).
d. Climate Effects
The deforestation and overgrazing have impacted the lake severely. The evaporation from the lake is greater than four times the rainfall rate (Eric et.al). Rainfall in the area has decreased considerably which led to a warmer climate and in turn high water extraction.
e. Socio-economic Effects
The decrease in level of the lake has impacted largely the farmers, fishermen, and herders living in the region. Crop failure, dying of livestock, and collapsed fisheries have resulted. Conflicts have emerged between nations and dwellers of the lake area. Two big projects; the South Chad Irrigation Project (SCIP) in Nigeria and the MAMDI Polder Project in Chad have been abandoned due to the shrinkage of the lake.
f. Hydrological Effects
The main tributary of the lake (90%) is the Chari River (Chad) which is fed by the Logone (Chad/Cameroon border) River. The remaining 10% is from the Yobe River (Niger/Nigeria). The Lake Chad Basin Commission (LCBC) has proposed an interbasin water transfer scheme from the Ubangi River. The shrinkage of the lake has affected the flows in the major rivers by decreasing it and the lowering of the groundwater table. Ground water is a major source of water in the area. As this source is also a challenge to harness, groundwater management is necessary (Mallam , 1999).
i. Campbell, Robert Wellman, ed. 2008. “Lake Chad, West Africa: 1963, 1973, 1987, 1997, 2007.” Earthshots: Satellite Images of Environmental Change. U.S. Geological Survey. http://earthshots.usgs.gov.
ii. Coe, M., and J. Foley (2001), Human and natural impacts on the water resources of the Lake Chad basin, J. Geophys. Res., 106(D4), 3349-3356.
iii. Eric O. Odada, Lekan Oyebande, Johnson A. Oguntola, Lake Chad, Experience and lessons Learned Brief
iv. Shrinking African Lake Offers Lesson on Finite Resources, National Geographic News by Hillary Mayell, April 26, 2001 http://news.nationalgeographic.com/news/2001/04/0426_lakechadshrinks.html
v. Lake Chad Evaporation 1963 to 1997, NASA, http://svs.gsfc.nasa.gov/vis/a000000/a002000/a002064/index.html
vi. A Shadow of a Lake: Africa’s Disappearing Lake, NASA http://www.gsfc.nasa.gov/topstory/20010227lakechad.html
vii. Lake Chad, http://www.solcomhouse.com/africalchad.htm
viii. Lake Chad to be fully protected as international wetlands, National Geographic Blog, February 02, 2010.
ix. NASA websites
x. Shrinking African Lake Offers Lesson on Finite Resources, National Geographic News, By Hillary Mayell, April 06, 2006.
xi. Wikipedia the free encyclopedia
xii. Groundwater Management Perspective for Borno and Yobe States, Nigeria, Journal of Environmental Hydrology, Mallam Zaji Bunu, Hohai University Nanjing, China, 1999
2. Aral Sea
The Aral Sea is a saline basin in Central Asia lying between the countries of Kazakhstan and Uzbekistan. It had an area of 68,000km2 before it was shrunk to 10% by 2007. In 1960 it was the fourth largest sea in the world. The shrinkage of the Sea has resulted in the formation of four lakes; North Aral Sea, Eastern Basin (South Aral Sea), Western Basin (South Aral Sea), and a smaller lake between the North and South Aral Sea. Of these four lakes, the Eastern Basin has already disappeared in 2009 and the Western Basin has decreased to a thin strip. The main reason for the shrinkage is attributed to the diversion of the river that fed the Sea by the former Soviet Union for the purpose of cotton irrigation since the 1960s. Two major rivers flow into the Sea, the Syr Darya (from Kazakhstan) and the Amu Darya (from Uzbekistan). The Sea has a catchment area of 1,549,000 km2. The Sea basin lies in five countries; Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan.
Fishing was the major activity. It was responsible for the jobs of about 40,000 people. The rivers flowing into the Sea were used for cotton irrigation. Both rivers have been diverted signiifcantly in order to increase cotton production.
The main reason for the shrinkage is attributed to the diversion of the river that fed the Sea by the former Soviet Union for the purpose of cotton irrigation since the 1960s. In addition to the abstraction of water irrigation, canals are not properly lines. This inefficiency will cause the loss of huge volume of water which otherwise would have in flowed to the Sea. The Kazakhstan government has built a restoring project for the North Aral Sea by constructing the Kokaral Dike in 2005. The construction of this dike has increased the level of water in the North Aral Sea by 24m in the year 2007.
d. Climate Effects
The local climate has changed, the summer becoming hotter and drier while the winter has become colder and longer.
e. Socio-economic Effects
The fishing industry that has been a job opportunity for over 40,000 people is already closed due to the shrinkage. The Sea area has a serious health problem. The Sea is highly polluted with toxic chemicals from weapon testing, fertilizers and pesticides. The dry land that resulted from the shrinkage of the South Aral Sea has given an opportunity for oil and gas exploration since 2006. The restoration of the North Aral Sea by the construction of theKokaral Dike has increased the number of fishes which increased the fishing activity. Accumulation of salt has also led to the loss of cultivable land.
f. Hydrological Effects
The South Aral Sea is disappearing even though ground water recharges it. The construction of the Kokaral Dike has brought changes such as the recovery of sea level in the North Aral Sea, a rain cloud presence and micro climate change in the area. On the contrary, South Aral Sea is decreasing. The eastern part of the South Aral Sea is hit by intermittent flooding which makes it difficult for vegetation. Natural effects have been slower on the Sea while human factors are rapid.
- The Sea shrunk to 2/5 of its original size
- Water level dropped by 16m
- Its volume decreased by 75%
- All the fish species are extinct
- It is estimated that 75M tons of toxic dust and salt are spread across central Asia each year
g. Researches undertaken
Different research has been completed on the Aral Sea. The major areas of focus are, optimization of water use, chemical and biological characteristics of the Sea, and rehabilitation of the Sea. Different optimization models have been developed. Multi objective model analysis framework has been considered as part of negotiations by taking the case of the Syr Darya River (Ximing Cai and Daene C. McKinney).
h. Institutions formed
There are number of institutions formed to alleviate the problem of the Sea shrinkage.
- Interstate Commission for Water Coordination of Central Asia (ICWC)
This institution is formed between Republic of Kazakhstan, Kyrgyz Republic, Republic of Tajikistan, Turkmenistan, and the Republic of Uzbekistan.
- International Fund for Saving the Aral Sea (IFAS)
This is the result of the ICWC member countries which is formed to raise fund for any Aral Sea based program.
i. A Multiobjective Analysis Model for Negotiations in Regional Water Resources Allocation, Ximing Cai and Daene C. McKinney,
v. Results of Aral Sea studies, Nick Aladin, Philip Micklin, Dietmar Keyser, Igor Plotnikov, Rene Letolle, Alexey Smurov and Jean-Francois Cretaux, 2006
vi. Sustainable Water Management in The Aral Sea Basin, Daene C. McKinney, Department of Civil Engineering The University of Texas at Austin, 1997
vii. The rehabilitation of the ecosystem and bioproductivity of the Aral Sea under conditions of water scarcity, INTAS Project – 0511 REBASOWS, Summary Report, December 2006/revised August 2007
viii. Water security and ecosystem services: The critical connection, Ecosystem Management Case Studies, United Nations Environment Program, Nairobi, Kenya May, 2009
3. Fossil Water
Fossil water is a non-renewable resource which is also called paleowater.
- The most notable fossil water reserve is in the Nubian Sandstone Aquifer System (NSAS) (covering the northeastern part of Africa). This aquifer system borders four countries; Chad, Egypt, Libya, and Sudan. Its area covers a little above 2 million square kilometers. The geology of the aquifer is generalized as hard ferrugios sandstone with great shale and clay interaction
- Lake Vostok (in Antarctica). It is the largest sub glacial lake. It is confined by an ice cape which has a depth greater than 3km. This overburden pressure keeps the water liquid even at a temperature below freezing point. The lake is thought to be the most unspoiled lake on earth. Life is thought to be supported in the lake.
- Great Artesian Basin (in Australia)
- Sahara and Kalahari Deserts.
- The fossil water in the NSAS was largely explored in Libya while drilling for oil purpose in the 1950s.
- The existence of Lake Vostok was first noted by the scientists from Scott polar Research Institute (SPRI) in 1973. It was delineated in 1996 by Russian and British scientists. A joint Russian, French, and U.S. drilled a core to analyze the lake water characteristics. In this drilling, the age of the lake was estimated to be between 500, 000 and one million years while it was also suggested that the lake supports life. Recently the Russian Antarctic Expedition is drilling using new equipment to the lake body (as the previous drills were abandoned 100m before reaching the lake to avoid any contamination of the lake.
- In addition to the above specific studies, NASA has taken images of aquifers which are the major tools for any study to follow and which are still going on.
Of all the fossil water reserves that have been identified, the following countries use it for different purposes like:
- Libya-Water supply, Irrigation
- Jordan-Water Supply ( in the future, not at present)
- Australia-Irrigation, Horticulture, Mining, Water Supply
Different projects are ongoing and some are proposed for the future. The followings are some examples;
The Great Man-Made River Project (GMMR) has been in place since 1984. The project costs US$20 Billion which consists of a network of pipes (4,000km in length and 4m diameter) and reservoirs. The water will be drawn from 1, 300wells. The daily discharge conveyed is 6.5Mm3.
The Dakhleh Oasis Project (DOP) is underway in the Dakhleh Oasis since 1978. It studies the interaction between environmental change and human activities. This project doesn’t have a direct use/abstraction objective.
- Chad, Egypt, Libya, and Sudan
An international project is underway which involves the NSAS Countries, IAEA, UNDP/GEF (Global Environment Facility), and UNESCO.
Jordan has proposed to transport water from its Disi Desert to Amman with a project named Disi Water Conveyance Project. The project will convey 100Mm3 of water annually to the capital. But, the water quality from this source has a high level of radiation (20 times higher than the normal level).
The use of fossil water in Negev Desert is ongoing as an alternative to using sewage water.
i. “Fossil Water” in Libya, NASA,
iii. The Role Of Fossil Water On Climate – An Important Climate Forcing Whose Influence Has Not Yet Been Properly Assessed, a blog on Climate Science by Dr. Roger Pielke Sr., https://pielkeclimatesci.wordpress.com/ , October 2010.
iv. Underground “Fossil Water” Running Out, National Geographic News, http://news.nationalgeographic.com/news/2010/05/100505-fossil-water-radioactive-science-environment/ , by Brian Handwerk, May 6, 2010
v. The Water Resources of Israel, Past, Present, and, Future, A review prepared for The Palestinian Center for Regional Studies (PCRS), A comprehensive outline, By Arie S. Issar, Ben Gurion University of the Negev, April 2000.