Feasibility of Water Distribution System Upgrades to Allow Functionality After an Earthquake Using the System Augmentation for Use After an Earthquake Method

Abstract

Water systems can become nonfunctional after earthquakes due to pipe failure along fault lines or soil liquefaction. A new algorithm is introduced here that adds scientific originality and advances the current state-of-the-art in earthquake disaster management. Network modeling was performed to investigate the feasibility of making the system more resilient and robust so as to allow continued use after an earthquake until the leaks can be isolated and repaired. Improvements considered were a dedicated tank feed line used to supply water from the source, across the fault line or liquefaction area, to the reservoir tank, along with an upgrade of the system perimeter pipes. The analysis method, termed the System Augmentation for Use After an Earthquake Method (SAEM), is demonstrated on a realistic system. It was found that these upgrades are able to make the system robust enough to continuously provide water after an earthquake until repairs can be made. For the system studied, for example, to successfully breach a fault line, and depending on the break size, the pump may have to be increased up to four sizes (in capacity), the new feed line over the fault up to three sizes, and perimeter pipes increased by three pipe sizes. Similarly, for a liquefaction neighborhood along the main line, the pump may have to be increased up to three sizes, the new feed line over the fault up to two sizes, and perimeter pipes increased by three pipe sizes. The new SAEM analysis method can be used on any system, however.