KARACHI - Speakers at a meeting organised by the Friends of Indus Forum here on Sunday called for stopping disposal of untreated agricultural, industrial and domestic effluents in natural water bodies that has resulted in serious surface and ground water contamination, especially with spreading salinity. Dr Mohammad Yar Khuhawar Professor Emeritus University of Sindh Jamshoro, while presenting findings of his study on post flood monitoring of water quality and sediments in Manchhar Lake, said that Manchhar is extensively contaminated due to the addition of untreated agricultural waste water. The study has been conducted in collaboration with WWF. The Manchhar Lake, he said continues to be used for domestic purposes by the communities living around the Manchhar, because the ground water within the area is saline and not suitable for drinking. The treated water provided by government agencies is not sufficient to meet the needs of inhabitants. Dr Khuhawar further added that the study was undertaken during April –June 2012. The sampling scheme was repeated three times. The water and sediments samples were monitored for 27 parameters including total dissolved salts (TDS), electrical conductivity(EC), dissolved oxygen(DO), chloride, total hardness, alkalinity, nitrate, nitrite, ammonia, sulfate, orthophosphate, total phosphate, biological oxygen demand (BOD), sodium, potassium, calcium, magnesium, cobalt, lead, nickel, chromium, manganese, copper, zinc, cadmium and iron. The bottom sediments were examined for the water extractable total and bioavailable metal contents. Coefficient of correlation among physicochemical parameter and metal ion, cluster analysis and contamination index for water and sediments were calculated. A number of parameters for water crossed WHO permissible limits with high contamination index at Manchar and MNVD. Dr Khuhawar stated that the excessive evaporation of the water from the surface of water at high atmospheric temperature before monsoon season is pushing the salts contents to higher side. The agricultural waste water while passing through the agricultural lands extracts the salts, nutrients and trace elements, which are added to main stream and eventually reach up to a Manchar. Some of them are precipitated in the bottom sediments and others stay in water body. Nasir Ali Panhwar highlighted the importance of linkages between universities and regulating bodies such as EPA to take forward the recommendations made by research studies. Ghulam Mustafa Mirani said that Manchar Lake must be revived considering its ecological, social and economic significance. Dr Ali Murtaza Dharejo suggested that impacts of water on local communities must be studied extensively. Majeed Mangrio said that Chotirai dam has affected indigenous vegetation, which is almost vanished now. Ali Akbar Rahmoon, Prof. Qalander Shah, Aziz Ranjhani, Ishtiaque Ansari, Shahid Panhwar, Altaf Shaikh, Ishaque Mangrio, Altaf Mahaser, Sadar Jatoi, Asif Sandelo and others also spoke at the occasion.