RISK-BASED PLANNING AND OPTIMIZATION OF FLOOD MANAGEMENT MEASURES IN DEVELOPING COUNTRIES Case Pakistan Muhammad Atiq Ur Rehman Tariq Risk-based planning and optimization of flood management measures in developing countries: Case Pakistan Proefschrift ter verkrijging van de graad van doctor aan de Technische Universiteit Delft, op gezag van de Rector Magnificus prof. ir. K.C.A.M. Luyben, voorzitter van het College voor Promoties, in het openbaar te verdedigen op maandag 19 december 2011 om 15:00 uur door Muhammad Atiq Ur Rehman Tariq M.Sc. in Engineering Hydrology Centre of Excellence in Water Resources Engineering, University of Engineering and Technology Lahore, Pakistan geboren te Multan, Pakistan Dit proefschrift is goedgekeurd door de promotor: Prof. dr. ir. N. C. van de Giesen Copromotor: Dr. ir. O. A. C. Hoes Samenstelling promotiecommissie: Rector Magnificus voorzitter Prof. dr. ir. N. C. van de Giesen, Technische Universiteit Delft, promotor Dr. ir. O. A. C. Hoes, Technische Universiteit Delft, copromotor Prof. dr. Ir. Pieter van der Zaag, UNESCO-IHE Delft/ Technische Universiteit Delft Prof. ir. Han Vrijling, Technische Universiteit, Delft Prof. dr. ir. Bart Schultz, UNESCO-IHE Delft/ Technische Universiteit Delft Prof. dr. ir. Arjen Hoekstra, Universiteit Twente, Enschede Dr. ir. P.H.A.J.M. van Gelder, Technische Universiteit Delft Prof. dr. ir. J.B. van Lier Technische Universiteit Delft, reservelid Keywords: risk-based flood management, developing countries, expected annual damages, optimal risk point, structural measures, flood zoning, flood insurance Copyright © 2011 by Muhammad Atiq Ur Rehman Tariq Contact: [email protected] Cover designed by: Dr. Van Tuan NGUYEN ISBN: 978-90-6562-284-6 © All rights reserved. No part of the material, protected by this copyright notice, may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage and retrieval system, without prior written permission from the author. Printed in the Netherlands. To ‘Munir Akhtar’ may her soul rest in the Heaven (Amin) ̶ Although circumstances did not allow her to finish her own education, she succeeded to motivate me, her son, to complete mine… Acknowledgements A number of persons, organizations, and groups have helped to shape my work as it is presented in this thesis. I would thank Allah Almighty for his blessings that enabled me to produce this research work. When I chose TU Delft for my PhD, I was planning to do research filled with obscure terminology and complicated formulae. Questions of Prof. Nick van de Giesen and Dr. Olivier Hoes forced me to think first on the fundamentals of flood management practices that, as a result, changed my topic, motivations, and the targets of research. I am indeed thankful for their critical and innovative questions and their support. Scholarship for this research was awarded by HEC Pakistan under the cherished motivation of then chairperson Prof. Dr. Ata Ur Rehman. I would cordially thank him, who turned the education opportunities towards the deserving students under open merit schemes. I would like to extend my sincere thanks to Adam J. Pel, Shahzad Akhtar, and Sandra Junier for sparing their precious time to review chapters of this thesis. As well as, Martine Rutten, who translated the Summary and Qianqian Zhou, who provided innovative ideas employing adaptation possibilities, thank you both. Many thanks are due to Yasir Abbas for providing necessary data. I am also thankful to all of my colleagues for their support to facilitate my research and helping me in many ways. I wish to stay in contact with all of them. Back in Pakistan, my father Al Haaj Shafi Muhammad Bhatti who remained always waiting for my successful return. I cannot forget the support of my seniors, Brig. (R) Ali Mansoob Raza and Engr. Ayub Tabassam, who made all efforts for me to proceed with my PhD. My friend Wasif Ali always motivated me to complete my PhD as early as possible. I always pray for them from the core of my heart. My wife Maria, my daughter Eshaal Areej Fatima and my sisters always remained my sound support during my stay in the Netherlands. I would thank my brothers Shafiq Ur Rehman and Laiq Ur Rehman as well as my in-laws Mr. Majeed Baloch & family for all their help in every aspect of my life. Muhammad Atiq Ur Rehman Tariq vii viii Summary Problem statement Among all the natural hazards, floods claim most lives and highest financial losses. About 95-97% of all deaths and a significant part of economic losses caused by floods occur in developing countries. Despite spending considerable resources, flood management arrangements in developing countries are still unable to deliver satisfactory results. Limited resources, lack of research, and absence of proper planning are the main constraints towards the optimization of flood management in developing countries. Flood management plans are often accomplished with the financial and technical help of developed countries following their design methodologies and safety standards. Such plans are often not suitable for local conditions. Flood safety standards for developed countries may not produce the most efficient results when applied in developing countries. Objectives The subject of this thesis is flood management in developing countries, focusing on fluvial floods, with special focus on Pakistan. To address this issue, the development of a methodology that can appropriately consider the socio-economic and technical constraints of a country is crucial. This thesis intends to provide guidance for flood managers and land-use planners that develop a floodplain. Their general concerns can be described as: How much should land-use planners curtail developments and how much should the river be regulated to minimize flood risks? For a satisfactory solution of these concerns, a risk-based methodology is introduced and outcomes are compared with locally used and worldwide well-established methods. In other words, the objective of this thesis is to develop a method ‘to maximize advantages by minimizing flood deductions in a floodplain, using the available resources’. Flood management in Pakistan Flood management in Pakistan is a resource-demanding and complex issue. A complete understanding of the problem and the existing setup is important. The nature of the problem of flooding varies extremely over the country depending on the hydrological, topographical, and demographical conditions. Considerable resources have been deployed over time since the country came into being in 1947. Despite deploying major financial resources and institutional support, flood management is still not appropriately optimized at the national level. The recent devastating flood in 2010 raised concerns over the reliability of existing flood management arrangements. ix Risk-based flood management Like most countries, Pakistan also uses probability-based flood safety standards (using a 50-years return period) for flood protection structures. To design flood protection measures according to probability-based standards, only flood characteristics need to be considered. Moreover, these standards do not provide guidance for the design of non- structural measures. A risk-based flood management approach provides the logical grounds for the selection and design of flood measures, whether structural or non- structural. It incorporates fairness and uniformity, and provides a firm basis to flood management practices. Risk calculations should not ignore the advantages of floodplain usage for productive purposes, like residential, industrial, and agricultural use. Risk- based analysis provides a systematic methodology to optimize flood management. Components of flood risk To estimate and minimize the risk of flooding at any location within the floodplain, it is important to know the basic components of risk and understand their role in inducing risk. Although risk mechanics have been defined differently in literature, this research proposes alternative, more appropriate, concept that considers all independent components of risk while avoiding redundancy. In this research, risk is defined as the result of the interaction between ‘hazard’ and ‘vulnerability’. While a hazard can be characterized by its intensity and probability, vulnerability depends on ‘susceptibility’ and ‘exposure’. The understanding of risk mechanics is important to select appropriate flood management measures with optimized design. Cost benefit analysis Cost benefit analysis (CBA) is a requisite for risk-based assessment. Multi-objective or multi-criteria analysis (MCA) may also be incorporated as a part of CBA for the optimization purposes. Careful valuation of economic, social, and environmental assets is indispensable for the precision of CBA. These analyses are often used to determine the feasibility of projects nowadays. Benefit to cost ratio (BC Ratio), Present Value (PV), Internal Rate of Return (IRR), and Economic Rent (ER) are economic efficiency indicators commonly used for the evaluation of projects. These indicators help to best utilize investments, but do not explicitly correlate the targeted flood management arrangements to the optimal arrangements. Expected annual damages The proposed risk-based assessment method helps decision-makers to envisage the spatial and temporal distribution of risk over the floodplain. Direct and indirect losses due to floods are related to the occurrence of floods, whereas investments in measures consist of the initial