You are here -allRefer - Reference - Country Study & Country Guide - Iran >

allRefer Reference and Encyclopedia Resource

allRefer    
allRefer
   


-- Country Study & Guide --     

 

Iran

 
Country Guide
Afghanistan
Albania
Algeria
Angola
Armenia
Austria
Azerbaijan
Bahrain
Bangladesh
Belarus
Belize
Bhutan
Bolivia
Brazil
Bulgaria
Cambodia
Chad
Chile
China
Colombia
Caribbean Islands
Comoros
Cyprus
Czechoslovakia
Dominican Republic
Ecuador
Egypt
El Salvador
Estonia
Ethiopia
Finland
Georgia
Germany
Germany (East)
Ghana
Guyana
Haiti
Honduras
Hungary
India
Indonesia
Iran
Iraq
Israel
Cote d'Ivoire
Japan
Jordan
Kazakhstan
Kuwait
Kyrgyzstan
Latvia
Laos
Lebanon
Libya
Lithuania
Macau
Madagascar
Maldives
Mauritania
Mauritius
Mexico
Moldova
Mongolia
Nepal
Nicaragua
Nigeria
North Korea
Oman
Pakistan
Panama
Paraguay
Peru
Philippines
Poland
Portugal
Qatar
Romania
Russia
Saudi Arabia
Seychelles
Singapore
Somalia
South Africa
South Korea
Soviet Union [USSR]
Spain
Sri Lanka
Sudan
Syria
Tajikistan
Thailand
Turkmenistan
Turkey
Uganda
United Arab Emirates
Uruguay
Uzbekistan
Venezuela
Vietnam
Yugoslavia
Zaire

Iran

Water

Iran's land surface covers 165 million hectares, more than half of which is uncultivable. A total of 11.5 million hectares is under cultivation at any time, of which 3.5 million hectares were irrigated in 1987, and the rest watered by rain. Only 10 percent of the country receives adequate rainfall for agriculture; most of this area is in western Iran. The water shortage is intensified by seasonal rainfalls. The rainy season occurs between October and March, leaving the land parched for the remainder of the year. Immense seasonal variations in flow characterize Iran's rivers. The Karun River and other rivers passing through Khuzestan (in the southwest at the head of the Gulf) carry water during periods of maximum flow that is ten times the amount borne in dry periods. Several of the government's dam projects are on these rivers. In numerous localities, there may be no precipitation until sudden storms, accompanied by heavy rains, dump almost the entire year's rainfall in a few days. Often causing floods and local damage, the runoffs are so rapid that they cannot be used for agricultural purposes.

Water shortages are compounded by the unequal distribution of water. Near the Caspian Sea, rainfall averages about 128 centimeters per year, but in the Central Plateau and in the lowlands to the south it seldom exceeds 10 to 12 centimeters, far below the 26 to 31 centimeters usually required for dry farming (see Climate , ch. 2).

Scarcity of water and of the means for making use of it have constrained agriculture since ancient times. To make use of the limited amounts of water, the Iranians centuries ago developed man-made underground water channels called qanats that were still in use in 1987. They usually are located at the foot of a mountain and are limited to land with a slope. A qanat taps water that has seeped into the ground and channels it via straight tunnels to the land surface. The qanats are designed to surface in proximity to village crops.

The chief advantage of the qanat is that its underground location prevents most of the evaporation to which water carried in surface channels is subject. In addition, the qanat is preferable to the modern power-operated deep well because it draws upon underground water located far from the villages. The chief disadvantages of the qanat's are the costs of construction and maintenance and a lack of flexibility; the flow cannot be controlled, and water is lost when it is not being used to irrigate crops.

In the late 1980s, an estimated 60,000 qanats were in use, and new units were still being dug (although not in western Iran, where rainfall is adequate). To assist villagers, the government undertook a program to clean many qanats after the Revolution in 1979. Qanat water is distributed in various ways: by turn, over specified periods; by division into shares; by damming; and by the opening of outlets through which the water flows to each plot of land. So important is the qanat system to the agricultural economy and so complex is the procedure for allocating water rights (which are inherited), that a large number of court cases regularly deal with adjudication of conflicting claims.

Construction of large reservoir dams since World War II has made a major contribution to water management for both irrigation and industrial purposes. Dam construction has centered in the province of Khuzestan in the southwest as a result of the configuration of its rivers flowing from the Zagros Mountains. The upper courses flow in parallel stretches before cutting through the surrounding mountains in extremely narrow gorges called tangs. The terrain in Khuzestan provides good dam sites. The government set up the Khuzestan Water and Power Authority in 1959 to manage natural resources in that province. All economic development plans emphasized the need to improve water supplies and reservoirs so as to improve crop production. Large reservoirs were built throughout the country, beginning with the Second Development Plan. The first dams were built on the Karaj, Safid, and Dez rivers.

The first of the major dams had a significant impact on the Iranian economy. Completed in 1962, the Mohammad Reza Shah Dam on the Dez River was designed to irrigate the Khuzestan plain and to supply electricity to the province. After several years of operation, the dam had achieved only a small part of its goals, and the government decided that the lands below the dam and other dams nearing completion required special administration. As a consequence, a law was passed in 1969 nationalizing irrigable lands downstream from dams. The lands below the Mohammad Reza Shah Dam were later leased to newly established domestic and foreign companies that became known as agribusinesses.

Data as of December 1987

 

Iran - TABLE OF CONTENTS

The Economy

Go Up - Top of Page



Make allRefer Reference your HomepageAdd allRefer Reference to your FavoritesGo to Top of PagePrint this PageSend this Page to a Friend


Information Courtesy: The Library of Congress - Country Studies


Content on this web site is provided for informational purposes only. We accept no responsibility for any loss, injury or inconvenience sustained by any person resulting from information published on this site. We encourage you to verify any critical information with the relevant authorities.

 

 

 
 


About Us | Contact Us | Terms of Use | Privacy | Links Directory
Link to allRefer | Add allRefer Search to your site

allRefer
All Rights reserved. Site best viewed in 800 x 600 resolution.