Water Distribution System Case Study

CHAPTER 1

PROBLEM SETTING

1.1 Background of the Study Water distribution system all over the world is design to ensure hydraulic reliability including the adequate quantity and pressure of water for its intended purpose. It is a widely accepted fact that water distribution is susceptible to all types of hazards: natural or man-made (Mays, 1989). Governments defined water distribution system as a critical infrastructure essential for the functioning of society and economy. In line with the objective of securing the safety of water system, risk assessment has been developed as a tool in identifying the threats, vulnerabilities and providing measures for response and recovery. Water suppliers have the responsibility in providing safe and acceptable

Risk on water distribution system indicates the potential damage or loss affecting the functionality of the water supply. As a critical infrastructure, this system should always be functional at all times to ensure its continuous delivery for human consumption. Furthermore, there is a need for water utilities to develop their own risk analysis strategy for specific situations to ensure the public health of water supply.

Surigao Metropolitan Water District (SMWD) is mainly responsible in maintaining and operating the water supply within the province. Issues on water supply and quality are always present in all water systems. According to Ensomo, SMWD General Manager, there has been an alleged contamination of mercury of water system in 2012. Also in 2011, a diarrhea outbreak was declared in one of the barangay supplied by SMWD and it was believed that is due to contamination of drinking water. In 2012, SMWD admitted that they have been unable to provide enough water due to the severe drought in the province (Catoto, 2012). In 2013, continuous rain forced the water district to suspend water supply because of water turbidity (Almeda, 2013). From this, it can be drawn that the water system is vulnerable to natural hazards such as flood and rain; and

1.4. Hypotheses of the Study The purpose of the study is to develop a framework for risk reduction, response, recovery and remediation based on the hazard identification and risk analysis of HATSS. With this, the researcher formulated the following hypotheses:

a) Top hazards identified will have a significant effect on the water quality of the SMWD.

b) Risk estimation will show high or very high significant although control measures are identified for all risks.

1.5. Scope, Limitations and Delimitation The scope of the study area is in Surigao City. Specifically, it focuses on the main water distribution system handled by SMWD. The assessment will include all the elements of the water distribution system from the source to tap: system, sub-system and component. The data to be used in the study are classified into two: the system data that will be acquired from the local government of Surigao City, from SMWD itself, and PAG-ASA; and the event data that will be gather by the researcher from the records and statistics of the most common hazards occurring in the water system. The hazard identification tool to be used is through the concept of hazard analysis type-hazard analysis technique. A risk matrix will be used to determine the risk level of the identified hazards. The study will only focus on the hazards affecting the water quality. EPANET software