Rehabilitation of Esfahan City Sewer Network

For many decades, Esfahan city has dealt with diseases sourcing from human sewage. The traditional drinking water wells were surrounded by cesspools. Early 1961, Zarvan company won the tender of laying concrete pipes in central area of Esfahan in 80 Km length. Different ranges of diameter and shape helped the city to possess a modern sanitary waste-water collecting system. Since 1965, despite the city`s development and increase the length of swage network to 3600 Km, the lack of well-organized maintenance program has been quite obvious. A huge number of collapsing incidents which happened during these years indicated the weakness of pipe condition. Indeed, temporary repair to control the potential of risk were not really effective. Enormous amount of money has been spent on reactive cleaning methods. Engineering reports that is to say the whole asset is under continues heavy corrosion and that unexpected incidents are extremely probable. Although the Esfahan Water and Waste-water Organization was completely aware of the high risk situation, for many reasons, an integrated plan have not been made to solve the problem. Since 2005, the Ministry of Power led the Organization to invest on renovation of old network. For this purpose, Organization began to plan and collect budget. Mahab Ghods Consultant Company was selected to conduct pre-feasibility and feasibility studies before preparing biding document. Meanwhile, based on the Ministry`s policies, a Chinese bank was introduced as an investor for financing through Iran-China credit line. The flowing is the result of the work after few years: Foreign Financing, Inspection and Rehabilitation of Mains and Sub Mains of Esfahan Wastewater Collection System Project. It is designed to wash, inspect and rehabilitate around 300 Km of aged pipes in ranges of diameter 500 mm to 1800 mm. The method of inspection was designated robotic CCTV camera. The cleaning would be conducted by high pressure cleaning methods. It is determined to use latest technology for pipe rehabilitation and the trenchless approaches stipulated in the contract to achieve better network management. In the present essay, an attempt has been made to illustrate the limitations, resources, potentials, difficulties, and innovations which have been made circumference of this wonderful project.