Application Analysis of Online Monitoring in Tracing Illegal Connections in Sewage Pipe Networks—Taking the Central Urban Area of a Certain County in Jiangxi Province as an Example

为实现对市政污水管网精细化体检省时省力的目的，采用在线监测技术，对管网关键节点进行水位、流量、化学需氧量(COD)监测，通过数据分析，了解管网入流入渗状况，为管网混接溯源提供依据。分析结果显示：水位、流量、COD均能表征管网入流入渗状况；水位监测在项目实际应用中效果更佳。To achieve efficient and labor-saving refined inspection of municipal sewage pipe networks, online monitoring technology was employed to measure key parameters (water level, flow rate, and chemical oxygen demand (COD)) at critical pipeline nodes. Data analysis was conducted to assess inflow and infiltration (I/I) conditions, providing a basis for tracing cross-connections in the network. The results demonstrated that water level, flow rate, and COD can all characterize I/I conditions, with water level monitoring proving more effective in practical applications.