In order to ensure water safety, urban water supply enterprises should establish and improve the water quality early warning system, formulate emergency plans for water sources and water supply emergencies, and carry out emergency drills on a regular basis. Once an emergency occurs, it is necessary to report in time according to the plan and take effective measures to deal with it. In sudden water pollution accidents, especially the leakage of toxic and harmful chemicals, the inspectors should quickly take the necessary detection instruments and safety protection equipment, rush to the scene, and immediately use rapid detection means to identify and identify the types of pollutants, and give quantitative or semi quantitative test results. Items that cannot be confirmed or confirmed on site shall be sent back to the laboratory for analysis immediately. According to the monitoring results, determine the scope and degree of possible pollution, and report to the local environmental quality department in time. In the process of emergency treatment of water quality emergencies, urban water supply enterprises should strengthen the frequency of water quality detection of pipe blowing muffler, and increase the detection items if necessary. In the case that the standard monitoring and analysis methods in China can not meet the analysis requirements of sudden water pollution accidents, other advanced analysis methods at home and abroad can be used. Water quality assurance measures must be formulated before technical transformation, equipment renewal or maintenance.