The Koura area wastewaters are disharged into several streams which lead to Dahr El Ain river that disharges in the sea, in Bahsas area, at the Souhtern entrance of Tripoli city. Hydrogeologically, the Koura area constitutes the extension of the Miocene limestones aquifer, from which burst out 3 major springs (Dahr El Ain and Abou Halka) which waters are conveyed to Tripoli water treatment plant that supplies Tripoli city with drinking water. In addition, many wells have been drilled in that aquifer and are exploiting its water to contribute in the supply of water for some villages in Koura area and for Triploi city. Consequently, that aquifer is being pollutes through the direct recharge in the aquifer of the Koura wastewaters that flow along the streams crossing the Koura Plateau. A decision was taken by CDR to collect the Koura wastewaters and convey them at a first stage, directly to Dahr El Ain River , and in a second stage, to Tripoli wastewater treatment plant.

The design of all the Koura wastewaters collection and conveyance was awarded by CDR to BTD who prepared all the Tender documents and the Bills of Quantities. Then, BTD was awarded by CDR, through a bidding procedure, the construction supervision of Part I works which were financed by AFD and by the Lebanese Government.

The works of Part I, are limited to an area that encompasses 25 villages which population in 2025 is 99,857 and which population will be 136,830 in 2040. The average wastewater flows of 2025 are estimated at 15,058 and those of 2040 at 20,634 m3/d. The peak daily flow in 2040 is estimated at 43,375 m3/d