Parameters characterizing leakages from damaged water pipes in the aspect of environmental security

Abstract

Leakages from buried water pipes can result in suffosion posing a threat to the environment and the infrastructure existing in cities. Leakage of water from a pressure pipe into a soil susceptible to suffosion is a very complex phenomenon, characterized by a number of different parameters. Taking into account all parameters in the empirical tests of the buried water pipe leakage is practically impossible. Thus, it is necessary to select them so that on the one hand it is possible to perform a physical simulation of the phenomenon, and on the other to obtain reliable results of investigations. According to the Pareto principle, it can be stated that a small group of factors—about 20%—has a crucial impact on the phenomenon. Therefore, in empirical tests of water outflow from the underground water supply system, it is enough to consider 20% of the parameters affecting the analyzed phenomenon. The purpose of this work was to select these parameters. The selection was based on two types of research—literature research and computer simulations using the FEFLOW v. 5.3 software. The research allowed to select 4 out of 19 parameters which impact on the effects of the phenomenon of water outflow from pressure pipe to a soil susceptible to suffosion turned out to be the most essential: a pressure in the pipe, a leak area, a saturated conductivity coefficient of soil and an uniformity coefficient of soil.