Water Supply Development in Iran during Recent Drought

Transcription

1 Water Supply Development in Iran during Recent Drought Farid Karimpour 1, Seyed Hamed Alemohammad 2 Abstract Iran is located in one of the arid and semi-arid regions of the world and due to a dry weather, has faced the problem of water shortage for long times. This long lasting problem has forced people from old times to be prepared for drought. Today there are many institutions and organizations which are involved in supplying water in Iran. Water supply in Iran has faced many challenges in the recent years and as a result of low precipitation and the annual increase in water demand, Iran water sector passed through a severe condition in year By having a good capacity, Iran could go through the drought by a minimum loss. This capacity has been mostly developed before the drought and some were built by the drought condition. This paper goes through the condition of water supply system in the period of five years and the developments during the recent drought. The new capacities include institutional and structural aspects, which both have been explained here. The main purpose of these works has been to provide and distribute safe amount of water. The demand management during drought condition which was of high importance in this period has been explored in this paper too. The results show that Iran has got a new experience in facing critical conditions and this will be very helpful for future disasters. Keywords: Drought, Water Supply, Capacity Building, Demand Management 1. IRAN WATER RESOURCES 1-1. INTRODUCTION Having an average annual precipitation of 250 mm, Iran receives less than one third of global average precipitation. That is why the country is classified as a semi-arid country. In addition, the pattern of rainfall distribution over the country is not the same everywhere. The main reason for variability in precipitation amount over the country is the variation in physiographic setting and climatic features. The main physiographic features in the country could be mentioned as Zagros and Alborz mountain ranges striking northwest-southeast and west-east respectively, central deserts, Caspian Sea to the north and Orumieh Lake to the northwest part of the country. The rainfall varies from less than 50 mm per year in central deserts and southeast plains to more than 1900 mm per year in some coastal lands in the south west of Caspian Sea. Different physiographic features affect local climate and produce such variability in precipitation pattern. According to United Nations Sustainable Development Commission index and with regards to water scarcity, Iran is classified as a country with "severe" situation. Iran is located in arid and semi-arid area with restricted water resources, which are not more than 0.36 percent of the world fresh water resources whereas about 1 percent of 1 M.Sc. Student, Civil Engineering Department, Sharif University of Technology, Tehran, Iran, f_karimpour@civil.sharif.edu 2 Ph.D. Student, Civil and Environmental Engineering Department, Massachusetts Institute of Technology, MA,USA, hamed_al@mit.edu

2 the world population lives in the country. The mountainous areas are of good karstic water resources. In some plains which are nearby from these mountains ranges, the water resources are good but mostly of the plains in central, southern and eastern part of the country are poor from quantitative and qualitative point of view. 90% of the precipitation falls from October through May. This uneven distribution through the time leads to floods during rainy seasons and also dryness during the dry seasons. Spatially most of the rainfalls occur to the northern and northwestern parts and that is why most of the 3000 seasonal and permanent rivers in the country flow in this part. So the other parts of the country suffer from lack of water WATER RESOURCES SUPPLY The 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 is 417 BCM; Average annual evaporation & transpiration is 299 BCM; Surface currents are 92 BCM; Direct seepage to alluvial aquifers is 25 BCM; And also: About 72 percent of precipitation is not accessible due to evaporation and transpiration; About 22 percent of precipitation flows as surface water resources; About 6 percent of precipitation within the borders of the country is used for direct recharge of alluvial aquifers. Consequently, about 117 BCM of water is directly and potentially accessible by people through precipitation (internal renewable resources) each year. In addition to water resources gained through precipitation within the limits of the country, about 13 BCM of surface flow enters the country across its borders. When this flow is combined with the surface flow with internal origins, the total figure of surface water resources of the country increases to about 105 BCM. Of this amount, about 13 percent (13 BCM) is used for recharge of alluvial aquifers. Accordingly, annually about 130 BCM of water is accessible for people through precipitation and inflow currents across borders (total renewable resources). In addition to naturally processed water resources, about 29 BCM of exploited and consumed water from surface and groundwater resources appears again as exploitable surface water or penetrates to alluvial aquifers as reservoirs. Correspondingly, the total water resources of the country, including such water exchange processes, increase to about 159 BCM. Out of this, 82 percent (130 BCM) are renewable resources, and 18 percent (29 BCM) are return waters that are discharged into surface and groundwater resources and are included in the calculation of total water resources. As annual changes in quantity and quality of consumption patterns take place, this section of water resources also changes quantitatively and qualitatively WATER USE The greatest amount of water use (83.5 BCM or 92.8 percent) is by the agricultural sector. Of this amount, about 50 percent is exploited from surface water resources and another 50 2

3 percent from groundwater. Exploitation of water resources by the industrial sector is about 1.1 BCM or 1.2 percent of total use. About 54 percent of water utilization in this sector is from groundwater resources and the remaining amount is from surface water. Withdrawal of water by the urban and rural water supply sectors is about 5.4 BCM, or 6 percent of total water exploitation of the country, of which about 68 percent is from groundwater resources and the remaining 32 percent from surface water MAIN WATER BASINS Research and reports show that Iran can be divided into six main water basins; namely, the Caspian Sea, Orumieh Lake, Kashafroud, the Eastern Border, the Central Plateau, and the Persian Gulf and Oman Sea. These six main water basins are divided into 30 sub-basins (Figure 1). Figure 1. Iran s main Basins The characteristics of these main basins are displayed in Table 1. Table 1. Iran s main basins characteristics Basin Name Area (km 2 ) Precipitation (mm) Renewable Water (BCM) Caspian Sea 173, Orumieh Lake 51, Kashafroud 44, Eastern Border 107, Central Plateau 851, Persian Gulf and Oman Sea 419, RECENT DROUGHT CONDITION 2-1. HYDROLOGICAL STATUS In the last four years there has been a noticeable decrease in the amount of yearly precipitation and because of that Iran faced a severe drought condition. (Table 2) 3

4 Considering the Long-term average of precipitation in Iran which is about 250 mm, there has been a 45% loss in precipitation during water year It s worth noting that the long-term average is about 1/3 of the world average precipitation. So, Iran is in itself an arid country. Table 2. Iran s yearly precipitation Water Year Total Precipitation (mm) Considering the amount of water used for agriculture (92.8% as mentioned in the last section) Iran had a big challenge about agricultural productions and it was forced to import some of its wheat and rice demand in this period. For example in year 2009 Iran forced to import more than 7 million ton of wheat as a result of 60% loss in production of wheat. As 4 years before Iran announced that it was then capable of producing all of its domestic need for wheat, so, the current imports show the severe impacts of the current drought. About 20% of total electricity production of Iran is based on Hydropower plants. In summer 2008 due to water shortage, the hydropower plants could not supply the necessary amount of electricity and so there were regular electricity cuts in that season. Hopefully in water year the precipitation increased by about 55% with respect to previous year and improved the water supply of the country. In the same period the water supply in dams has increased by about 30 % to 16 MCM in June 2009, which has helped Iran to overcome the electricity shortage problem in summer The status of precipitation and run off in is presented in different basins in Tables 3 and 4. Table 3. Precipitation in (mm) Basin Name Water Year Water Year 40 year Percentage Difference w.r.t Average years Average Caspian Sea Persian Gulf Orumieh Lake Central Plateau Eastern Border Kashafroud Sum Table 4. Runoff in (BCM) Basin Name Water Year Water Year Long time Percentage Difference w.r.t Average Long-term Average Caspian Sea Persian Gulf Orumieh Lake Central Plateau Eastern Border Kashafroud Sum

5 2-2. DROUGHT INVESTIGATION In order to investigate the drought conditions we first define the proper index for drought categorization. Palmer Drought Severity Index (PDSI) is such an index of meteorological drought, values of which are calculated on the basis of precipitation and temperature data of the actual and preceding periods, as well as the available soil moisture content. The Palmer Drought Index is based on a supply-and-demand model of soil moisture. Supply is comparatively straightforward to calculate, but demand is more complicated as it depends on many factors - not just temperature and the amount of moisture in the soil but hard-tocalibrate factors including evapo-transpiration and recharge rates. Palmer tried to overcome these difficulties by developing an algorithm that approximated them based on the most readily available data precipitation and temperature. Table 5 presents different classes of drought based on PDSI. Table 5. Palmer Classifications PDSI Value Drought Class 4.0 or more Extremely Wet 3.0 to 3.99 Very Wet 2.0 to 2.99 Moderately Wet 1.0 to 1.99 Slightly Wet 0.5 to 0.99 Incipient Wet Spell 0.49 to Near Normal -0.5 to Incipient Dry Spell -1.0 to Minor Drought -2.0 to Moderate Drought -3.0 to Severe Drought -4.0 or less Extreme Drought The figures 2 and 3 show the status of drought based on global drought monitor. As it is observed in figure 2 in the last 36 months most of the parts of the country has had droughts from minor to exceptional drought. This is mainly due to 2008 drought. But in figure 3 it is obvious that although the vastness of drought is increased but its severity is decreased in October This is mainly due to the precipitation increase in water year The exceptional drought condition in the neighboring countries such as Iraq, Saudi Arabia and Kuwait is also noteworthy. 5

6 Figure 2. Drought Severity in Iran and neighboring region (based on last 36 months up to Oct. 2009) [3] Figure 3. PDSI in Iran and neighboring region (Oct. 2009) [3] 6

7 3. CHANGES IN INFRASTRUCTURE AND INSTITUTIONAL STRUCTURE In this section the changes that have been made in infrastructures and institutional structure of water management of Iran will be discussed INFRASTRUCTURE STATUS The current situation of storage dams in Iran is as follows: Table 6. Dams in Iran Situation No. Total Volume Regulating Volume (MCM) (MCM) Under Operation ,416 30,142 Under Construction ,430 10,921 Under Study ,767 12,847 There are more than 222 large dams (based on ICOLD definition) under operation and about 400 under construction and study in Iran. After the considerable changes in the water management structure of Iran in 2000, there was a huge increase in the rate of dam construction and the result was a properly good capacity to undergo the drought condition in the previous years. Table 7 displays the increasing trend of dam construction in and the continuing works up to Time Period Table 7. Dam Construction Trend in Iran Up to Total Volume (MCM) 12,268 2,472 1,155 2,180 14,716 6,625 39,416 The main changes of the last five years that have been added to the previous ones to increase the capacity of water supply can be summarized as follows: - Operating 17 new storage dams; - Operating two new transfer tunnels of 23.4 km length with capacity of 260 MCM / yr; - Starting the construction of 21 storage dams with regulating volume of MCM; - Constructing ha of Irrigation and Drainage Networks; - Operating 41 artificial recharging projects with recharging water of MCM/yr; From the point of view of institutional aspects there have been many changes in water management structure of Iran, which mainly was started in 2000 and continued up to present. After these changes, the most recent structures is as follows: A- POLICY-MAKING STRUCTURE Water High Council This council, organized under the supervision of the highest executive office (the President) and with representatives of the stakeholders present, is a mechanism to dialogue and to harmonize the policies and general plans of water resources management; 7

8 Parliament It is one of the three main bodies of the political structure of the country and the highest authority of legislation in various sections. B- EXECUTIVE ADMINISTRATIVE STRUCTURE (MINISTRY OF ENERGY) Deputy Minister for Water and Wastewater Affairs; Holding Company of Iran Water Resources Management and related subset companies (Water Sector); Holding National Water and Wastewater Engineering Company and related subset companies (Water and Wastewater Sector). C- TECHNICAL AND ENGINEERING STRUCTURE (PRIVATE SECTOR) 126 consulting entities; 216 contractors. One of the most important works in the drought condition was the demand management. In this respect the Ministry of Energy with collaboration with Ministry of Jihad-e- Agriculture and Department of Environment made a considerable work. The main purpose was to aware people of the importance of water, especially in drought condition and in an arid country such as Iran. These works can be classified as follows: - Public awareness program in public broadcasts such as T.V. and Radio; - Delivering awareness speeches in different gatherings and seminars for public and issuing regular articles in this regard in Daily Newspapers, Magazines, etc; - Producing and broadcasting animations about water saving; - Producing and distributing training brochures among people in different public events; - Determining 4 th of March as the National Water Day and performing public programs in cities all around the country (This was because the 22 nd March is the New Year s holiday in Iran). Beside all these works a good progress started to train children at elementary school about importance of water, so that they can aware their parents at home too. 4. CONCLUSIONS The paper presented the hydrological condition of Iran and its recent severe drought as a great loss of precipitation in Also, it was mentioned that by having a well developed capacity (infrastructural and institutional) Iran could go through the drought condition by less losses to public, although there were some financial losses due to electricity cut and decrease in food production. According to the above mentioned we can summarize the points as below: Drought has became a common phenomenon in Iran; It is necessary to consider meteorological parameters; 8

9 It is necessary to change from disaster management to risk management and also considering demand management; The drought programs to reduce drought impacts should be implemented by all stakeholders. All of these resulted in a good experience for Iran to face critical conditions in future. Based on the current experience and also previous droughts (2001) the following approaches and policies are recommended for drought condition: Merged consumption of surface and groundwater resources; Demand management approaches; Installing drought fore-warning system; Supplying water resources during drought via: o Trans-boundary conveyance; o Artificial groundwater recharge; o Cloud seeding; o Using water recycling methods; o Using unconventional waters. Continuing public awareness programs; 5. REFERENCES [1] Ardakanian, R., Overview of Water Management in Iran, Water Conservation, Reuse, and Recycling: Proceedings of the Iranian-American Workshop, The National Academies Press, pp 18-34, 2005 [2] Clarke, R., and King, J., "The Atlas of Water", Myriad Edition, Brighton, UK, 127 pp, [3] Database of Iran Dams Characteristics, Ministry of Energy, Holding Company of Water Resources Management of Iran, (Last Date Accessed: Oct. 10th 2009). [4] Global Drought Monitor, UCL Department of Space and Climate Physics, (Last Date Accessed: Oct. 16th 2009) [5] Iran s Monthly Water Balance Report, Holding Company of Water Resources Management of Iran, (Last Date Accessed Sep. 2009). [6] Islamic Republic News Agency (IRNA), (Last Date Accessed Sep. 2009). [7] Nikravesh, M., Ardakanian, R., Alemohammad, S.H., Institutional Capacity Development of Water Resources Management in Iran, Capacity Development for Improved Water Management, UNW-DPC & UNESCO-IHE Publication, pp , [8] Rahimi, H., Khaledi, H., Water crisis in the world and in Iran Proceeding of the first national conference on drought mitigation, Jihad Daneshgahi, Kerman, Iran,