Water lies at the heart of civilizations. Most of the advanced civilizations of ancient times emerged on the banks of major rivers. With the passage of time as economic, political and social relations became more complicated new urban communities emerged in areas other than river banks. Metropolitan Tehran is one such settlement.
The city, which was chosen as the seat of the Qajar government without geographical, political and social considerations, has always faced problems in meeting its water needs.
In the past qanats and springs would provide the water the city needed. The water coming in from these resources would be kept in reservoirs for later use. In fact, such water did not meet hygienic standards.
The idea to meet the city's water needs from remote sources dates back to the era of Amir Kabir. However, the first practical steps g that idea were taken more than 50 years ago and the city's first water facility became operational in 1955.
Tapping into clean water resources and application of modern treatment and transfer technologies have made it possible for millions of Tehran residents to have access to very high-quality water. It is hoped that proper policies and plans along with tireless efforts of water industry personnel will help sustain that trend in the future.

Supply and transfer of untreated water
First attempts to bring in water to Tehran from Karaj were made when Haj Mirza Aghasi was the chancellor and then during the chancellorship of Mirza Taghi Khan Amir Kabir. Eventually in 1931 a 53-km canal was dug to bring in water from Sarjoob village in Karaj to the capital's Jamshidabad neighborhood. The volume of the inflow stood at 140 stones. According to two documents, the share of Tehran from the Shahrestanak tributary of the river and its main stream was 53 and 9 stones respectively.
In 1954 studies to build the Karaj Dam 40 km to the northwest of the capital got underway. Actual construction of the facility started in 1958 and ended in 1964 when the dam was inaugurated.
Construction of Bilghan diversionary dam and two 40-inch steel pipelines (1955) and two concrete pipelines 2,000 mm in diameters (1965 and 1970) helped supply part of the capital's water from the Karaj River.
Population growth and a rise in demand prompted officials to launch studies to build another dam, this time 32 km to the northeast of the capital to contain the water of the Jajorood River. The project became operational in 1967 and the water was brought to Tehranpars water treatment centers 3 and 4 via a 9 km tunnel.

Features of untreated water transfer pipelines
Steel pipes: 73 km
Concrete pipes: 67 km
Tunnels: 28 km
Canals: 8 km

Abstraction of water from wells
In light of the fact that there was a limit to abstraction of water from Karaj, Lar and Latian Dams and the population was growing steadily, ground water resources began to be tapped in 1963 to meet the need of the capital for drinking water. The practice steadily grew in size and the number of wells increased by the day. At first wells were only used in late spring and during the summer but later year-round application of wells became inevitable. Today these wells play an undeniable role in supplying the drinking water of the capital. The chart below shows the share of runoff and ground water resources in meeting the need of the capital for drinking water in 2007.

Treatment of water
The project to bring tap water to some 900,000 residents of the capital was carried out in 1951. Back then two steel pipelines with a daily capacity of 256,000 cubic meters would transfer water from Bilghan Dam to the capital's Water Treatment Center 1 which became operational in 1955. As demand grew Tehran's second water treatment facility went on stream in 1963. Two concrete pipes 20,000 mm in diameter would transfer water to the facility from Bilghan Dam. After completion in 1957 of the construction work at the Latian Dam, 32 km to the northeast of the capital, water was channeled from there to Water Treatment Center 3 through a 9-km tunnel and the capital's fourth water processing plant became operational in 1984.
With the population and need for drinking water growing at a breakneck speed, efforts to meet the need of the capital gathered more momentum. In 1981 construction of the Lar earthen dam to the northeast of Tehran was completed. The dam which is built on a namesake river has two power plants and the water it releases is directed toward the Latian Dam. Part of Lar's water is brought to the capital's Water Treatment Center 5 through Ghoochak Tunnel. Phase one of the treatment facility which processes 7.5 cubic meters of water per second became operational in 2004.

Features of Tehran water treatment facilities
Water
Treatment
Facility

Inaugural date
Type of
clarifier
Nominal capacity
No. 1
(Jalaliyeh) 1955 Accelator 2.7 cubic meters per second
No. 2
(Kan) Two phases
1963 and 1970 Pulsator 8 cubic meters per second
No. 3
(Tehranpars) 1968 Pulsator 4 cubic meters per second
No. 4
(Tehranpars) 1984 Pulsator 4 cubic meters per second
No. 5 2004 Pulsator 7.5 cubic meters per second
Overall
capacity of
facilities Almost 26 cubic meters per second

Tehran pumping stations
To take water to areas which were located at a higher altitude, Tehran's first pumping station became operational in 1955 when Jalaliyeh water treatment facility was inaugurated. As the city expanded so did the number of pumping stations. In March 2008 that number stood at 55.

Pumping stations
Number of pumping stations: 50
Pumping capacity: 48.9 cubic meters per second
Maximum pumping height: 525 meters
Number of pumping stages: 8
Between 1,315 and 1,840 meters above sea level

Information on water distribution network (March 2008)
Length of distribution network: 8,700 km
Number of pumping stations: 46
Pumping capacity: 47 cubic meters per second
Number of storage tanks: 70
Capacity of storage tanks: 2 million cubic meters
Difference in altitude of highest and lowest points: 800 meters
Number of gas chlorinators: 56
Number of chlorination stations: 44
Number of emergency teams: 190
Number of distribution-related accidents: 350 a day
Amount of daily chlorine consumption: 3.5 tons

Reporter : mehdi akbarsefat

َApproved by : 28 , First name : mehdi akbarsefat

Create date : 6 Sep 2010 19:06

Id : 20482

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