April 7, 2005: Disappearing Lakes, Shrinking Seas

To see the text of the associated Eco-Economy Update, click here:
DISAPPEARING LAKES, SHRINKING SEAS

DISAPPEARING LAKES, SHRINKING SEAS: Selected Examples

Location	Name	Situation

Chad, Niger, Nigeria and Cameroon	Lake Chad	Lake Chad has shrunk by 95 percent from 25,000 square kilometers in the mid-1960s to 1,350 square kilometers in 2001, corresponding with increased irrigation (local agricultural water use quadrupled between 1983 and 1994) and decades of depressed rainfall.
Kenya	Lake Nakuru	The lake has shrunk in area since the 1970s from 48 to less than 37 square kilometers today. Nearby forests are being cleared for farmland to feed a fast growing population, causing soils to erode and wash into the lake. Failed urban sewage systems and unregulated industrial effluent have polluted the lake. Heavy metals in the water, including lead, zinc, mercury, copper and arsenic, have been linked to flamingo die offs.
Kazakhstan and Uzbekistan	Aral Sea	Excessive diversion of the Amu Darya and Syr Darya, largely for irrigation, has shrunk the 5 million year old lake to less than half of its 1960s size of 66,000 square kilometers. It now holds less than one fifth of its previous volume and has split into two sections. The southern section is unlikely to be restored. The shoreline of the Aral Sea has receded by up to 250 kilometers, leaving behind a salty contaminated desert. The sea could disappear entirely within 15 years.
Iran and Afghanistan	Hamoun Lakes in the Sistan Basin	Dams built on the Helmand River in Turkey and Afghanistan for hydroelectric power and "improved" water distribution, constructed largely in the 1970s, have reduced water reaching the lakes and marshland. As a result of the diversion, along with high evaporation rates, the lakes have shrunk. Harsh winds blow the fine sand from the exposed lakebeds, creating storms that can bury villages, fill irrigation canals, and decimate fish, livestock, and bird populations.
Israel	Sea of Galilee (Lake Galilee or Lake Tiberias)	The Sea of Galilee is Israel's largest freshwater lake, with a total area of 170 square kilometers and a maximum depth of approximately 43 meters. At 209 meters below sea level, it is the lowest freshwater lake on Earth and is expected to drop even lower as the lake shrinks and becomes saltier due to excessive water withdrawals, drought, and evaporation.
Jordan, Israel, and Palestine	Dead Sea	At 417 meters below sea level, the Dead Sea is the lowest place on earth, and is falling by up to 1 meter per year. Much of the water that would otherwise feed it is tapped by Israel and Jordan for irrigation. Overpumping Jordanian groundwater at more than twice the rate of aquifer recharge also has dropped the water table. The Sea has shrunk in length since the early 1900s, from over 75 to 55 kilometers long, and has split in two, with the southern basin turned into evaporation ponds for potash extraction. Its retreat has spawned more than 1,000 "sinkholes" of up to 20 meters deep and 25 meters across, forcing the evacuation of more than 3,000 people along the Jordanian shore alone. The salty lake could disappear entirely by 2050, along with the 90 species of birds, 25 species of reptiles and amphibians, 24 species of mammals, and 400 plant species that live on its shores.
India	Dal Lake	Lake Dal has shrunk from 75 square kilometers in 1200 AD to 25 square kilometers in the 1980s, to smaller than 12 square kilometers today. Over the last decade the lake has dropped 2.4 meters in height. Debris from floating gardens has accumulated and uncontrolled building activity has filled in large areas of the lake. All the untreated sewage of Srinagar city and some 1,400 houseboats is deposited directly into the lake. Other lakes in the Kashmir Valley are facing similar problems.
Pakistan	Lake Manchar	Diversion of the Indus River, largely for irrigation schemes, has deprived Manchar, Pakistan's largest lake, of fresh water. Salt content has increased dramatically in recent years and the polluted water fosters diseases previously absent from the region. The lake had been a source of fish for at least 1,000 years, but due to its deterioration some 60,000 fishers have left the area.
China	Northwest China's Xinjiang Uygur Autonomous Region	Lop Nur covered 2,000 square kilometers in the 1950s but since losing water to irrigation it has turned to salty land and desert. The western and eastern Juyan lakes, Aydinkol Lake, and Manas Lake have all suffered similar fates, losing water and shrinking to salt marshes and desert.
China	Yellow River (Huang He) Basin	Madoi County in the Tibetan Autonomous Prefecture of Golog in northwest China's Qinhai province, the first county through which the main stream of the Yellow River flows, once had 4,077 lakes. Over the past 20 years more than 2,000 lakes have disappeared. In Hebei province in the eastern part of the basin, falling water tables have contributed to the loss of 969 out of 1,052 lakes.
China	Yangtze River Basin	More than 13,000 square kilometers of lakes in the middle and lower reaches of the Yangtze River were lost over the last 50 years, resulting in the loss of about 500 million cubic meters of water storage capacity. More than 800 lakes disappeared entirely. This loss of water retention has contributed to increasingly severe flooding. Poyang Lake, China's largest freshwater lake, has shrunk to half its original size due to land reclamation, losing 4.5 cubic kilometers in volume. The second largest, Dongting Lake, has shrunk from 6,200 square kilometers 150 years ago to 4,350 square kilometers in the 1950s to 2,700 square kilometers today. The Chinese government has undertaken restoration and rehabilitation measures for lakes in the region.
Cambodia	Tonle Sap	Tonle Sap performs the important function of holding excess water during flood season, yet siltation from eroding farmland and deforested areas has reduced the lake's capacity and has destroyed aquatic habitat. Fish stocks that supply 75 percent of Cambodia's natural inland fish production are falling.
Russia	Lake Baikal	Lake Baikal, the world's oldest and deepest lake, contains nearly one fifth of the world's unfrozen freshwater. Over the past century the amount of soil flushed into the lake increased by two and half times due to regional agricultural and industrial development. Agricultural chemicals (including pesticides like DDT), power plants, and industry (particularly a large pulp mill on the lake's southern end) have polluted the lake.
Hungary	Lake Balaton	Central Europe's largest freshwater lake is shrinking, likely because of climate change. A series of warm and dry years elevated rates of evaporation above precipitation, causing the lake's shores to contract. Balaton's water quality has deteriorated since the mid-1940s, with major fish kills and algal blooms from eutrophication beginning in the 1960s. In the last two decades several regional management goals have been achieved, including diverting and treating sewage, reducing tourist and livestock numbers, and limiting sales of high phosphorous detergents, yet the lake is still in danger of damage from pollution.
Macedonia and Greece	Dojran Lake	Overuse of water from the lakes and streams that feed Dojran Lake has caused the lake to shrink to a third of its former size and the water temperature to rise. More than 50 islands have appeared in the middle of the lake as the water level has dropped by up to 3.48 meters below the minimal water level established in a 1956 bilateral agreement between Greece and Macedonia. Now with an average depth of 1.5 meters, the lake is turning into a swamp to the detriment of local plants and animals, especially fish. It is unlikely that the lake will ever return to its original size, and without action it soon may disappear.
Mexico	Lake Chapala	Mexico's largest lake is the main water source for Guadalajara's 5 million people. Its long-term decline began in the late 1970s corresponding with expanded agricultural development in the Río Lerma watershed. Since then, the lake has lost more than 80 percent of its water. Between 1986 and 2001, Chapala shrank from 1,048 to 812 square kilometers and its level dropped by up to 4 meters. Climbing municipal and industrial water demands now exceed sustainable supply by 40 percent. The lake’s contraction has come at the expense of certain fish species and potentially forebodes a change in the mild climate that the water supported. The lake also suffers from pollution from agricultural residues and heavy metals.
United States, California	Mono Lake	Mono Lake dates back at least 760,000 years and is an important feeding stop for tens of thousands of shore birds on their way to South American wintering grounds. Since the first diversions of its tributaries to quench the thirst of growing Los Angeles in 1941, the volume of the lake has contracted dramatically, going from 5.3 billion to 3.2 billion cubic kilometers. Its salinity climbed to almost three times that of the ocean--far too salty to sustain most fish. The lake likely would have died completely had locals not intervened and defeated Los Angeles in a legal battle for water.
United States, California	Owens Lake	This perennial lake in southeastern California held water continuously for at least 800,000 years, spanning 518 square kilometers at its peak, but since the mid-1920s, after a decade of diverting water from the Owens River to Los Angeles, the lake has been completely drained. The dry lake bed, which contains carcinogens including nickel, cadmium, and arsenic, as well as sodium, chlorine, iron, calcium, potassium, sulfur, aluminum, and magnesium, became the single largest source of particulate matter pollution in the United States, elevating air pollution in surrounding areas to up to 25 times the acceptable level under national clean air standards. Since 1998, Los Angeles has tried to abate these toxic dust storms by shallowly flooding a portion of the lake, reclaiming saline soils, and cultivating fields of salt tolerant grass using high-tech below-ground drip irrigation.
United States and Canada	Great Lakes	The Great Lakes basin holds 20 percent of global fresh water. Regional temperatures are projected to rise between 2 to 5 degrees Celsius by 2100, a warming that would decrease soil moisture and surface runoff and reduce water levels on the lower and middle Great Lakes by up to 70 centimeters by 2030. The volume of water in the five Great Lakes could drop by 25 percent by 2040 unless drastic action is taken to reduce consumption.

Source: compiled by Janet Larsen, Earth Policy Institute, from various sources, April 2005.

World Irrigated Agricultural Area, 1961-2002

Year	Irrigated Area	Annual Addition	Annual Change	Irrigated Area Per Person	Annual Change Per Person
	Thousand Hectares	Thousand Hectares	Percent	Square Meters	Percent

1961	139,136			452
1962	141,829	2,693	1.9	452	0.0
1963	144,501	2,672	1.9	451	-0.1
1964	147,161	2,660	1.8	450	-0.2
1965	150,155	2,994	2.0	450	0.0
1966	153,462	3,307	2.2	451	0.1
1967	156,492	3,030	2.0	450	-0.1
1968	159,922	3,430	2.2	451	0.1
1969	164,115	4,193	2.6	454	0.6
1970	168,034	3,919	2.4	455	0.3
1971	171,809	3,775	2.2	456	0.2
1972	175,488	3,679	2.1	457	0.1
1973	180,591	5,103	2.9	461	0.9
1974	184,177	3,586	2.0	461	0.1
1975	188,637	4,460	2.4	464	0.5
1976	192,853	4,216	2.2	466	0.4
1977	196,297	3,444	1.8	466	0.0
1978	204,442	8,145	4.1	477	2.4
1979	207,917	3,475	1.7	477	0.0
1980	210,222	2,305	1.1	474	-0.6
1981	213,554	3,332	1.6	473	-0.1
1982	215,772	2,218	1.0	470	-0.7
1983	219,373	3,601	1.7	470	-0.1
1984	223,641	4,268	1.9	471	0.2
1985	225,686	2,045	0.9	467	-0.8
1986	228,205	2,519	1.1	464	-0.6
1987	229,770	1,565	0.7	459	-1.1
1988	232,847	3,077	1.3	457	-0.4
1989	239,073	6,226	2.7	462	0.9
1990	244,988	5,915	2.5	465	0.8
1991	248,758	3,770	1.5	465	-0.1
1992	252,380	3,622	1.5	465	-0.1
1993	256,568	4,188	1.7	465	0.2
1994	258,993	2,425	0.9	463	-0.5
1995	262,304	3,311	1.3	462	-0.2
1996	264,586	2,282	0.9	460	-0.5
1997	267,918	3,332	1.3	459	-0.1
1998	269,900	1,982	0.7	456	-0.6
1999	273,318	3,418	1.3	456	-0.1
2000	275,188	1,870	0.7	453	-0.6
2001	275,881	693	0.3	449	-1.0
2002	276,719	838	0.3	445	-0.9

Source: Compiled by Earth Policy Institute from U.N. Food and Agriculture Organization, FAOStat, statistics database, at apps.fao.org, updated 2 July 2004; United Nations, World Population Prospects: The 2002 Revision (New York, February 2003).

Population by Country, 1950-2004, with
Projections to 2050

Link back to Eco-Economy Update Text

Close window

Aug	SEP	Oct
	03
2005	2006	2007