Some 70 per cent pump stations of Dhaka Water Supply and Sewerage Authority (WASA) are operating without dis-omfection system due to lack of chlorine gas, absence of operators and mechanical faults, endangering the public health in the city, sources said. According to a report of Dhaka WASA, the percentage of nonoperative dis-infection system has been increased to 70 per cent in December last from 66 in June. The number of pump stations under Dhaka WASA is 294.