IWRA World Water Congress 2008 Montpellier France
1. Water availability, use and management
AbstractStudy on the water availability in Iran, using
the international water indicators
Assistant Prof. Yazd University, Yazd,
The climate of Iran is one of great extremes due to its
geographic location and varied topography. The summer is extremely hot with temperatures in the interior rising
possibly higher than anywhere else in the world; certainly over 55°C has been recorded. Annual rainfall ranges from
less than 50 mm in the deserts to more than 1600 mm on the Caspian Plain. The average annual rainfall is 252 mm
and approximately 90% of the country is arid or semiarid. Overall, about two-thirds of the country receives less than
250 mm of rainfall per year.
In the last century (since, 1900) the population of Iran has increased about six-fold.
The population growth rate, which was less than 0.6 percent in the beginning of this period, reached the rate of 3.19
percent in the decade from 1976 – 1986. Fortunately; it has considerably decreased once again in the last decade.
The major changes in population growth rate, resulting from reduction of mortality and increase of natural growth
rate, occurred in the 1960s and afterward. In the period from 1961-2000, the urban population increased by about
31.7 million and the rural population increased by 11 million. In 1956, there were only three cities with a population
over 250,000 in Iran, while in 2000 the number of cities with a population of over one million reached seven.
direct impact of population growth on the water resources management of the country was an increased need for
potable water in population centers. Indirect impacts were increased demand for agricultural products, development
of irrigated lands, and the need for job opportunities and more income, especially in the agricultural sector.
main source of water resources throughout the country is annual precipitation. According to studies carried out for
formulation of the Water Comprehensive Plan, the main characteristics of annual precipitation and its conversion to
water resources are as follows:
• Average annual precipitation 417 bcm
• Average annual evaporation &
transpiration 299 bcm
• Surface currents 92 bcm
• Direct seepage to alluvial aquifers 25
This paper reviews and assesses water scarcity indicators in Iran based on the international indicators.
The most widely used indicator, the Falkenmark indicator, is popular because it is easy to apply and understand but
it does not help to explain the true nature of water scarcity. The International Water Management Institute model
(IWMI model), The Water Resources Vulnerability Index and the Water Poverty Index are the other international
indicators that are evaluated for the water resources situation and availability of water in Iran.