Flood Hazard Zoning of Tarlac City: Towards the Development of Flood
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Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect ScienceDirect AvailableProcedia online Engineering at www.sciencedirect.com 00 (2017) 000–000 Procedia Engineering 00 (2017) 000–000 www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia ScienceDirect Procedia Engineering 212 (2018) 69–76 7th International Conference on Building Resilience; Using scientific knowledge to inform policy 7thand International practice in disaster Conference risk reduction,on Building ICBR2017, Resilience; 27 Using – 29 Novemberscientific knowledge 2017, Bangkok, to inform Thailand policy and practice in disaster risk reduction, ICBR2017, 27 – 29 November 2017, Bangkok, Thailand Flood Hazard Zoning of Tarlac City: Towards the Development of Flood Hazard Zoning of Tarlac City: Towards the Development of Flood Overlay Zones and Provision Flood Overlay Zones and Provision Dr. Murphy P. Mohammed* Dr. Murphy P. Mohammed* College of Engineering, Tarlac State University College of Engineering,Tarlac City, TarlacPhilippines State University Tarlac City, Philippines Abstract Abstract The province of Tarlac in the Philippines is one of the commonly flooded areas due to its geographical characteristics.The province The of provinceTarlac in is the surrounded Philippines by i s highone ofmountains the commonly along itsflooded eastern areas and due western to its outskirtsgeographical but characteristics.predominantly theThe province province is a isvast surrounded flat area. by high mountains along its eastern and western outskirts but predominantlyThe present the study province focuses is a on vast the flat developme area. nt of flood model for the urban areas of Tarlac City wherein a flood overlayThe zonepresent is studydeveloped focuses based on the on developme the floodnt hazardof flood model. model Specifically,for the urban areasthe study of Tarlac focuses City on wherein attaining a flood the overlayfollowing zone objectives: is developed to develop based a floodon the inundation flood hazard model; model. to determine Specifically, the haz theards study on the focuses existing on land attaining use as wellthe followingas determine objectives: the susceptibility to develop to a floodflood hazardinundation and determinemodel; to determinethe risks on the the haz urbanards onbarangays; the existing and land to look use intoas well the asimplications determine ofthe land susceptibility use policies to towards flood hazard risk management. and determine the risks on the urban barangays; and to look into the implicationsHistorical, of landanalytical use policies and qualitative towards riskmet hodsmanagement. were employed to attain the objectives of the study. Stakeholders in theH istorical,City Disaster analytical Risk and Reduction qualitative and met Managementhods were employedCouncil (CDRRMC) to attain the wereobjectives involved of the in study.the formulation Stakeholders of inpolicies the City and Disaster strategies Risk which Reduction may lessen and the Management flood hazards Council as well (CDRRMC) as the risks weretowards involved the urban in the communities. formulation The of policiesoutcome and of thestrategies workshop which will may be incorporated lessen the flood to the hazards updated as comprehensive well as the risks land towards use plan the (CLUP) urban communities. of Tarlac City. The outcome of the workshop will be incorporated to the updated comprehensive land use plan (CLUP) of Tarlac City. © 2017 The Authors. Published by Elsevier Ltd. © 2018 The Authors. Published by Elsevier Ltd. ©Peer 201-review7 The Authors.under responsibility Published by of Elsevier the scientific Ltd. committee of the 7th International Conference on Building Resilience. Peer-review under responsibility of the scientific committee of the 7th International Conference on Building Resilience. Peer-review under responsibility of the scientific committee of the 7th International Conference on Building Resilience. Keywords: Flood Hazard Zoning, Flood Overlay Zones, Risk Management Keywords: Flood Hazard Zoning, Flood Overlay Zones, Risk Management *Corresonding author. Tel.: +639228142577 * CorresondingEmail address: author.:[email protected] Tel.: +639228142577 Email address: :[email protected] 1877-7058 © 2017 The Authors. Published by Elsevier Ltd. 1877Peer--review7058 © under 2017 responsibilityThe Authors. Publishedof the scientific by Elsevier committee Ltd. of the 7th International Conference on Building Resilience. Peer-review under responsibility of the scientific committee of the 7th International Conference on Building Resilience. 1877-7058 © 2018 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of the scientific committee of the 7th International Conference on Building Resilience 10.1016/j.proeng.2018.01.010 10.1016/j.proeng.2018.01.010 1877-7058 2 M.P.Mohammed/ Procedia Engineering 00 (2017) 000–000 70 Murphy P. Mohammed / Procedia Engineering 212 (2018) 69–76 M.P.Mohammed/ Procedia Engineering 00 (2017) 000–000 3 1. Introduction 1. To develop a flood inundation model. 2. To determine the flood hazard and susceptibility on the existing land use and to determine the risks on the The Philippines is one of the countries around the world oftentimes experiencing disasters such as earthquake, urban barangays. volcanic eruption, typhoon, tsunami, drought, as well as flooding among others. Flooding is the most frequently 3. To look into the implications of land use policies towards risk management. experienced phenomenon in the Philippines due to the monsoon rains and typhoons experienced by the country. On average, the country experiences about 20 typhoons (more or less) per year. On the other hand, monsoon rain affects 3. Research Methodology the weather system of the country for about six months or half of the year. This causes flooding in many parts of the country. Excessive rainfall runoff can cause urban flooding as well as breach on river dikes or levees which likewise can The study involved historical, analytical and qualitative methods to obtain its objectives. As regards historical cause flooding to low lying towns and villages. Damage to property, agriculture, as well as loss of lives may be method, rainfall data were gathered from the Philippine Atmospheric, Geophysical and Astronomical Services encountered during floods. The Philippines experienced several disasters related to flooding which caused many Administration (PAG-ASA). Rainfall data from the synoptic station in Tarlac City were acquired from the Agno deaths and damage to property in the last decade. River Flood Forecasting and Warning Center (ARFFWC) of PAG-ASA. The province of Tarlac in the Philippines is one of the commonly flooded areas due to its geographical Analytical method considered in the study was 2D flood hazard modeling. The use of geographic information characteristics. The province is surrounded by high mountains along its eastern outskirt (part of Nueva Ecija and system (ArcGIS version 10.2), LIDAR/SAR DEM data, raster and vector images of the study area, rainfall data, and Aurora provinces) and western outskirt (province of Zambales) but predominantly the province is a vast flat area. FLO-2D Basic software were utilized in the study. The province of Tarlac has 17 municipalities and one city. Qualitative method involved in the study was the conduct of workshops with the stakeholders of Tarlac City. The population of Tarlac City is 342,493, based on the 2015 National Statistical Coordination Board (NSCB) The stakeholders were identified by the Tarlac City government whom it wished to involve in the aforesaid data [1]. There are 141,439 people residing in the urban barangays whereas in the rural barangays there are 201,054 workshop. The stakeholders were involved in the formulation of policies and strategies which may lessen the flood residents. hazards and risks towards the urban communities based on the results of the developed flood hazard modelling. According to the City Disaster Risk Reduction and Management Office (CDRRMO), several barangays in the Officials present during the workshop were from the: City Planning and Development Office; City Environment and city were identified as flood prone, heavily flooded areas, and/or isolated during heavy rains. Based on the record of Natural Resources Office; City Social Welfare and Development; City Engineering Office; City Disaster Risk the CDRRMO, 17 out of the 76 barangays or 22.37 percent are prone to flooding. Reduction and Management Office; and representative from the City Administrator’s Office. The Comprehensive Land Use Plan (CLUP) of Tarlac City was approved in 2003 and to be adapted up to 2010. In 2014, the Housing and Land Use Regulatory Board (HLURB) released a new guide to comprehensive land use 4. Results and Discussions plan preparation. The following year, Tarlac City initiated to update the CLUP. Unfortunately, several years passed but the new CLUP of Tarlac City is yet to be approved. 4.1. Flood Inundation Model Section 13.2 of the 2014 CLUP Guidebook of the HLURB states that flood overlay zone regulations are applied in areas that have been determined in the CLUP as flood-prone. The objective of the flood overlay zone is to protect The current study developed several flood hazard models based on the 2-year, 5-year, 10-year, 15-year, 25-year, lives and properties from the harmful effects of flood [2]. 50-year, and 100-year extreme rainfall data gathered from the Agno River Flood Forecasting and Warning Center