Failure analysis and assessment on the exemplary water supply network

The subject of this paper is a failure analysis of water supply failure frequency in one of the cities in Poland. Operating data on the failure rate of water supply pipelines in the city were used. The analysis of water pipes' failures, including pipes diameters, their age, the material they are made from and their function in the water supply subsystem in the city was made. There is a noticeable downward trend in both the number of failures as well as the failure rates of water pipes. The value of failure rate indexes corresponds to national and international trends. The average failure rate for the main pipelines is λMavg = 0.98 km− 1 a− 1, the distribution pipelines λRavg = 0.42 km− 1 a− 1 and the water connections - λPavg = 0.35 km− 1 a− 1. The majority of failures (45.62%) happen in the distribution pipelines, representing about 53% of the total length of the pipelines. Detailed analysis of the water network failure should be a main element of the managing system of the urban water networks, particularly in strategic modernization plans.