18. Othman, S. Bacterial Quality of Drinking Water in Rain-Fed Cisterns and Roof Storage Tanks in Beit-Leed and Safarine Villages. Master’s Thesis, An-Najah University, 2000: 70pp.

This is a study concerning water quality in two villages in Tulkarem district, Safarine and Beit-Leed. Three hundred drinking water samples were collected from two storage systems (cisterns and roof storage tanks). The samples were collected from June to October 1999. Average counts for both total coliform and thermotolerent coliform (E.coli) were used as indicators for water quality based on membrane filtration technique. Both indicators gave average counts higher than that recommended as safe drinking water by the WHO. Total coliform counts were 16.1 and 12 CFU/100ml water in cisterns and roof storage tanks respectively, while average counts of thermotolerent coliform E.coli were 7.0 and 5.4 CFU/100ml water for cisterns and roof tanks respectively. Roof storage tanks showed lower average counts for both indicators.