The latest tender, released in late February, calls for international and local companies to bid for a contract to provide supervision services on the construction of the project's estimated $44 million eastern trunk main. TSC says the project involves the construction of an 18-kilometre tunnel with a diameter in the range of 2,000-3,000 millimetres and laying of concrete pipes (see Tenders). Contractors are set to be invited in the second quarter for two contracts to build the eastern trunk main, costing an estimated $44 million.

The project is part of a larger tender package for the construction of 116 kilometres of interceptors, 2,274 kilometres of laterals and two trunk mains. The local Loshan Companylast July was awarded the $22 million contract to install the western trunk line, which stretches over a distance of 23 kilometres. Other local companies have been awarded, and are awaiting the award of, contracts worth a total of more than $200 million for laterals and interceptors.

At least six groups of local and international companies have prequalified and have been approved by the World Bank to bid in May for the construction of the wastewater treatment plant, to be located in southern Tehran. The estimated $64 million project will be awarded on a design-build-operate basis. The plant's capacity will be 450,000 cubic metres a day by the end of phase 1 to serve a population of 2.1 million. During phase 2, to be implemented between 2006-11, capacity will be doubled to cover 4.2 million people.

Phases 3-5 of the wastewater scheme will see the expansion of the network and the construction of an additional plant in southwestern Tehran to serve a population of 10.5 million by 2029.

A team of Austria's ILF Consulting Engineers, Kuwait's KEO International Consultantsand the local Parsconsultwas appointed last July to provide consultancy services and technical assistance to TSC. The contract covers updating the investment development programme, institutional development and project management, and engineering design and construction supervision on phase 1 of the scheme. The team is also working on a feasibility study and engineering design for subsequent phases (MEED 13:7:01).

Implementation costs of phase 1 are estimated to reach about $340 million, $145 million of which will be provided by the World Bank. The bank in May 2000 agreed to resume lending to Iran after a gap of seven years and despite US pressure. The loan has a maturity of 17 years.

TSC is providing parallel financing of $195 million.