60起管网及二次供水污染事故分析

Analysis on 60 Pollution Accidents of Municipal Water Distribution Network and Secondary Water Supply System

了解管网及二次供水污染事故的发生特点和原因。搜集国内近20年来的管网及二次供水污染事故案例。管网及二次供水污染以生物性污染为主 ,占73 3 % ;除居民小区和企事业单位外 ,学校和单位家属区是重要的污染事故发生地 ,发生率均占11 7 % ;污染环节以自来水管网和高低蓄水池为主 ,占51 7 %和43 3 %。污染原因主要是管网及二次供水设施出现渗漏或破裂 ,污水倒灌 ;设施与污水管相连引起负压虹吸现象 ;

To understand the characteristics and causes of the pollution accidents of municipal water distribution network and secondary water supply system.Data on the pollution accidents of municipal water distribution network and secondary water supply system having occurred in recent 20 years were collected and analyzed. The main pollution type of municipal water distribution network and secondary water supply system was biological pollution,the amount of which took 73.3% of the total accidents.The pollution accidents mainly occured in schools or colleges and residential buildings offered by some enterprises to their members and families with an occurrence rate of 11.7%,besides residential quarters,enterprises and institutions.The main links of pollution were observed in municipal water distribution system(51.7%)and water storage tanks high and low lying(43.3%).The main causes of pollution accidents were the leakage and breakage facilities and mislink between the water pipes and sewage pipes, which resulted in formation of negative pressure.Siphonage and sewage flowing backward,in addition the poor sanitary protection facilities polluted by sewage and rubbish. It was the top priorities to establish special legal system,to enhence the preventive sanitary inspection