Comparative analysis of water–pipe network deterioration–case study

The paper presents a comparative analysis of water-supply network deterioration in three Polish cities. The comparison was made on the basis of operating data (from the period 2007 to 2012) received from water utilities. The comparison is necessary to determine whether and to what extent water utilities should improve the technical condition of their water-supply networks. On average in cities A, B and C, failure rates λ (fail km⁻¹ a⁻¹) of water mains, distribution pipes and house connections were 0.20, 0.24 and 0.53; 0.17, 0.32 and 0.50; and 0.01, 0.48 and 1.63, respectively. The failure rates of the main and distribution conduits were higher in winter than summer, due to the weather conditions and the pipes' shallow depth. Smaller diameter pipes were more vulnerable. One city is exposed to mining exploitation and most cracking observed on the main and distribution pipelines arose from this. As the literature and these investigations indicate, the technical condition of water supply systems in Poland is still improving and rates of deterioration decreasing.