Handbook of engineering hydrology environmental hydrology and water management (volume 2)

Water Science and Engineering While most books examine only the classical aspects of hydrology, this threevolume set covers multiple aspects of hydrology and includes contributions from experts comprising more than 30 countries It examines new approaches, addresses growing concerns about hydrological and ecological connectivity, and considers the worldwide impact of climate change It also provides updated material on hydrological science and engineering, discussing recent developments as well as classic approaches Published in three books, Fundamentals and Applications; Modeling, Climate Change, and Variability; and Environmental Hydrology and Water Management, the entire set consists of 87 chapters and contains 29 chapters in each book The chapters in this book contain information on • • • • • •  he anthropocenic aquifer, groundwater vulnerability, and hydrofracturing T and environmental problems Disinfection of water, environmental engineering for water and sanitation systems, environmental nanotechnology, modeling of wetland systems, nonpoint source and water quality modeling, water pollution control using low-cost natural wastes, and water supply and public health and safety Environmental flows, river managed system for flood defense, stormwater modeling and management, tourism and river hydrology, and transboundary river basin management The historical development of wastewater management, sediment pollution, and sustainable wastewater treatment Water governance, scarcity, and security The formation of ecological risk on plain reservoirs, modification in hydrological cycle, sustainable development in integrated water resources management, transboundary water resource management, and more Students, practitioners, policy makers, consultants, and researchers can benefit from the use of this text Environmental Hydrology and Water Management Environmental Hydrology and Water Management Eslamian Handbook of Engineering Hydrology Handbook of Engineering Hydrology K15218 ISBN: 978-1-4665-5249-4 90000 781466 552494 K15218_COVER_final.indd Tai Lieu Chat Luong 2/3/14 12:58 PM Handbook of Engineering Hydrology Environmental Hydrology and Water Management Handbook of Engineering Hydrology Handbook of Engineering Hydrology: Fundamentals and Applications, Book I Handbook of Engineering Hydrology: Modeling, Climate Change, and Variability, Book II Handbook of Engineering Hydrology: Environmental Hydrology and Water Management, Book III Handbook of Engineering Hydrology Environmental Hydrology and Water Management Edited by Saeid Eslamian MATLAB® is a trademark of The MathWorks, Inc and is used with permission The MathWorks does not warrant the accuracy of the text or exercises in this book This book’s use or discussion of MATLAB® software or related products does not constitute endorsement or sponsorship by The MathWorks of a particular pedagogical approach or particular use of the MATLAB® software CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2014 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S Government works Version Date: 20140115 International Standard Book Number-13: 978-1-4665-5250-0 (eBook - PDF) This book contains information obtained from authentic and highly regarded sources Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint Except as permitted under U.S Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers For permission to photocopy or use material electronically from this work, please access www.copyright.com (http:// www.copyright.com/) or contact the Copyright Clearance Center, Inc (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400 CCC is a not-for-profit organization that provides licenses and registration for a variety of users For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com Contents Preface vii Editor xi Contributors xiii Anthropocenic Aquifer: New Thinking Artificial Recharge Experiences in Semiarid Areas 17 10 11 12 Anthony Richard Turton and Frederik Stefanus Botha Noureddine Gaaloul and Saeid Eslamian Disinfection of Water and Nanotechnology 51 Seyedeh Matin Amininezhad, Sayed Mohamad Amininejad, and Saeid Eslamian Environmental Engineering for Water and Sanitation Systems 65 Bosun Banjoko Environmental Flows 85 Sara Shaeri Karimi, Mehdi Yasi, Jonathan Peter Cox, and Saeid Eslamian Environmental Nanotechnology 105 Saeid Eslamian, Raheleh Malekian, and Mohammad Javad Amiri Formation of Ecological Risk on Plain Reservoirs .119 Svetlana Dvinskikh, Alexander Kitaev, Victor Noskov, and Olga Larchenko Groundwater Vulnerability 145 Jason J Gurdak Historical Development of Wastewater Management 163 Giovanni De Feo, Georgios Pericles Antoniou, Larry Wesley Mays, Walter Dragoni, Hilal Franz Fardin, Fatma El-Gohary, Pietro Laureano, Eleni Ioannis Kanetaki , Xiao Yun Zheng, and Andreas Nikolaos Angelakis Hydrofracturing and Environmental Problems 219 Bosun Banjoko Modeling of Wetland Systems 233 Jennifer M Olszewski and Richard H McCuen Modifications in Hydrological Cycle 247 Jayantilal N Patel v vi Contents 13 Nonpoint Source and Water Quality Modeling 261 14 River Managed System for Flood Defense 299 15 Sediment Pollution .315 16 Stormwater Modeling and Management 329 17 Stormwater Modeling and Sustainable Management in Highly Urbanized Areas 347 Zhonglong Zhang Akram Deiminiat and Saeid Eslamian Qin Qian Xuheng Kuang J Bryan Ellis and Christophe Viavattene 18 Integrated Water Resource Management and Sustainability 365 19 Sustainable Wastewater Treatment 387 20 Tourism and River Environment 401 21 Transboundary River Basin Management 421 22 Transboundary Water Resource Management 433 23 Updating the Hydrological Knowledge: A Case Study 445 24 Water Governance 461 25 Water Pollution Control Using Low-Cost Natural Wastes 485 26 Water Resources Assessment in a River Basin Using AVSWAT Model 501 27 Water Scarcity 519 28 Water Security: Concept, Measurement, and Operationalization 545 29 Water Supply and Public Health and Safety 555 Husain Najafi and Ehsan Tavakoli-Nabavi Erik Grönlund Akram Deiminiat, Hassan Shojaee Siuki, and Saeid Eslamian David Stephenson and Eva Sbrana Inga Jacobs and Anthony Richard Turton Olga Eugenia Scarpati, Eduardo Kruse, Marcela Hebe Gonzalez, Alberto Ismael Juan Vich, Alberto Daniel Capriolo, and Ruben Mario Caffera Colin Green and Saeid Eslamian Faezeh Eslamian and Saeid Eslamian Aavudai Anandhi, V.V Srinivas, and D Nagesh Kumar R.B Singh and Dilip Kumar Chansheng He, Lanhui Zhang, Xifeng Zhang, and Saeid Eslamian Theodore C Crusberg Index 577 Preface Hydrological and ecological connectivity is a matter of high concern All terrestrial and coastal ecosystems are connected with water, which includes groundwater, and there is a growing ­u nderstanding that “single ecosystems” (mountain forest, hill forest, mangrove forest, freshwater swamp, peat swamp, tidal mudflat, and coral reef) that are actually the result of an artificial perception and classification can, in the long term, only be managed by a holistic vision at the watershed level It is essential to investigate ecosystem management at the watershed level, particularly in a changing climate In general, there are two important approaches: Adaption to hydrological events such as climate change, drought, and flood Qualitative and quantitative conservation of water, thereby optimizing water consumption The Handbook of Engineering Hydrology aims to fill the two-decade gap since the publication of David Maidment’s Handbook of Hydrology in 1993 by including updated material on hydrology science and engineering It provides an extensive coverage of hydrological engineering, science, and technology and includes novel topics that were developed in the last two decades This handbook is not a replacement for Maidment’s work, but as mentioned, it focuses on innovation and provides updated information in the field of hydrology Therefore, it could be considered as a complementary text to Maidment’s work, providing practical guidelines to the reader Further, this book covers different aspects of hydrology using a new approach, whereas Maidment’s work dealt principally with classical components of hydrologic cycle, particularly surface and groundwater and the associated physical and chemical pollution The key benefits of the book are as follows: (a) it introduces various aspects of hydrological engineer­ing, science, and technology for students pursuing different levels of studies; (b) it is an efficient tool helping practitioners to design water projects optimally; (c) it serves as a guide for policy makers to make appropriate decisions on the subject; (d) it is a robust reference book for researchers, both in universities and in research institutes; and (e) it provides up-to-date information in the field Engineers from disciplines such as civil engineering, environmental engineering, geological engineering, agricultural engineering, water resources engineering, natural resources, applied geography, environmental health and sanitation, etc., will find this handbook useful Further, courses such as engineering hydrology, groundwater hydrology, rangeland hydrology, arid zone hydrology, surface water hydrology, applied hydrology, general hydrology, water resources engineering, water resources management, water resources development, water resources systems and planning, multipurpose uses of water resources, environmental engineering, flood design, hydrometeorology, evapotranspiration, water quality, etc., can also use this handbook as part of their curriculum vii viii Preface This set consists of 87 chapters divided into three books, with each book comprising 29 chapters This handbook consists of three books as follows: Book I: Fundamentals and Applications Book II: Modeling, Climate Change, and Variability Book III: Environmental Hydrology and Water Management This book focuses on environmental hydrology and water management The chapters can be categorized as follows: • Groundwater management: Anthropocenic Aquifer: A New Thinking, Artificial Recharge Experiences in Semiarid Areas, Groundwater Vulnerability, and Hydrofracturing and Environmental Problems • Purification, sanitation, and quality modeling: Disinfection of Water and Nanotechnology, Environmental Engineering for Water and Sanitation Systems, Environmental Nanotechnology, Modeling of Wetland Systems, Nonpoint Source and Water Quality Modeling, Water Pollution Control Using Low-Cost Natural Wastes, and Water Supply and Public Health and Safety • Surface water management: Environmental Flows, River Managed System for Flood Defense, Stormwater Modeling and Management, Stormwater Modeling and Sustainable Management in Highly Urbanized Areas, Tourism and River Environmental Hydrology, and Transboundary River Basin Management • Wastewater and sediment management: Historical Development of Wastewater Management, Sediment Pollution, and Sustainable Wastewater Treatment • Water law: Water Governance, Water Scarcity, and Water Security: Concept, Measurement, and Operationalization • Water resources management: Formation of Ecological Risk on Plain Reservoirs, Modification in Hydrological Cycle, Sustainable Development in Integrated Water Resources Management, Transboundary Water Resource Management, Updating the Hydrological Knowledge: A Case Study, and Water Resources Assessment in a River using AVSWAT Model About 200 authors from various departments and across more than 30 countries worldwide have contributed to this book, which includes authors from the United States comprising about one-third of the total number The countries that the authors belong to have diverse climate and have encountered issues related to climate change and water deficit The authors themselves cover a wide age group and are experts in their fields This book could only be realized due to the participation of universities, institutions, industries, private companies, research centers, governmental commissions, and academies I thank several scientists for their encouragement in compiling this book: Prof Richard McCuen from the University of Maryland, Prof Majid Hassanizadeh from Utrecht University, Prof Soroush Sorooshian from the University of California at Irvine, Profs Jose Salas and Pierre Julien from Colorado State University, Prof Colin Green from Middlesex University, Prof Larry W Mays from Arizona State University, Prof Reza Khanbilvardi from the City College of New York, Prof Maciej Zalewski from the University of Łodz´-Poland, and Prof Philip B Bedient from Rice University ix Preface In addition, Research Professor Emeritus Richard H French from Las Vegas Desert Research Institute, who has authored the book Open Channel Hydraulics (McGraw-Hill, 1985), has encouraged me a lot I quote his kind words to end this preface: My initial reaction to your book is simply WOW! Your authors are all well known and respected and the list of subjects very comprehensive It will be a wonderful book Congratulations on this achievement Saeid Eslamian Isfahan University of Technology Isfahan, Iran MATLAB® is a registered trademark of The MathWorks, Inc For product information, please contact: The MathWorks, Inc Apple Hill Drive Natick, MA 01760-2098 USA Tel: 508-647-7000 Fax: 508-647-7001 E-mail: info@mathworks.com Web: www.mathworks.com Water Supply and Public Health and Safety 563 (4) high iron concentrations that form a rust-colored water; and (5) certain decomposition products of plants such as humic acids A measure of turbidity is used to indicate water quality and filtration effectiveness (e.g., whether disease-causing organisms are present) Higher turbidity levels are often associated with the potential for the water to carry higher levels of disease-causing microorganisms such as viruses, parasites, and some bacteria Sediment can protect adsorbed bacteria and viruses from disinfection by hiding pathogens within the structure of the sediment particles, allowing them to be eventually ingested by consumers Sediment can even react with those same disinfectants reducing their concentrations to levels that will be inadequate to protect the water from pathogens that would have been normally inactivated by the disinfectant chemicals Turbidity is quantifiable since it is a principal physical characteristic of water because the particulate matter will cause light to be scattered and absorbed rather than be transmitted in straight lines through a water sample The technology used to quantify turbidity uses the nephelometric, turbidimeter, or nephelometer (from the Greek word nephelè, meaning clouds or cloudiness in this case), which determines turbidity by the light scattered at an angle of 90° from an incident beam and has been adopted by Standard Methods as the preferred means for measuring turbidity because of its sensitivity, precision (reproducibility), and applicability over a wide range of particle size and concentration and is stated in terms of nephelometric turbidity units or NTU Removal of turbidity from drinking water has been shown to correlate with pathogen removal [13] Handheld commercial turbidity meters cost in the vicinity of $1000 It is common to install a continuous monitoring turbidimeter at the entry to drinking water distribution systems should a reference be needed for any particular hour or day of any week 29.5.4  Dissolved Matter: Salt (NaCl) and Total Dissolved Ions Note that the term used here is “constituents” and not “contaminants.” That is because contaminant refers to the introduction of constituents through human action of some kind Salt or sodium chloride, that is, NaCl, is a natural constituent of almost every water source and is a very soluble component of native rocks and soils As water percolates over rock faces or through the soils of the subsurface, salt naturally is released and dissolves in the water as sodium cations (Na+) and chloride (Cl−) anions Rocks, even those of granitic origins, are slowly, over millennia, decomposed by symbiotic lichens on their surfaces liberating a variety of salts, many of which are used by nearby plants for some of the nutrients required for their growth During such decomposition, many metallic elements are liberally released and, if soluble, can enter nearby water sources Salt in drinking water is also derived from natural salt deposits, seawater infiltration into aquifers, as well as infiltration of sewage and industrial wastes, agricultural chemicals applied to fields and in areas of the temperate world salt applied to roads for deicing purposes, and salt storage facilities for road salt Private and municipal wells located along major interstate highways are often impacted by road salt that can exceed 240 pounds of salt (108.7 kg) per lane mile during a snow or ice storm Although Boston, Massachusetts, obtains its potable water supply from distant well-protected upland reservoirs, there are several surface reservoirs in the greater Boston area that serve smaller communities, and with the density of the population and major highways that have been built around the city, the smaller surface supplies are seriously impact by winter salt use Concern over salt is based not only on taste but on its effect on cardiac health We can taste salt concentrations above around 0.015 M (876 mg/L NaCl or 532 mg/L Cl ion) in water [4], but health professionals and many governmental regulatory bodies suggest (usually not require) that we drink water that tests under 20 mg/L NaCl, a level too often unable to be met Only 1%–2% of the 4000–6000 mg that we ingest daily is actually derived from drinking water The value of 20 mg/L is actually derived from the fact that some individuals on salt-restricted diets should only ingest 500–1000 mg/day of sodium, and this allows them no more than 40 total mg from their drinking water Adding insult to injury is the fact that several water treatment technologies add salt to drinking water especially if sodium fluoride is employed to ward off tooth decay in children served 564 Handbook of Engineering Hydrology: Environmental Hydrology and Water Management by that water supply and in the use of sodium hypochlorite as a disinfectant when the use of chlorine gas is for one reason or another not feasible Even water-softening devices add sodium, which is used to replace magnesium and calcium ions that are constituents that give water a hardness factor (by making it hard for soap to clean clothes) Many states in the United States that use deicing salts on their roadways during winter months have reduced the amount used per lane mile, and some states now substitute calcium or magnesium chloride, but the latter does crystallize in a way on a windshield from the melted snow or ice spray while driving on the highway that can impede vision of the road ahead (author’s observation) Salt storage piles on department of public works yards are now covered to protect them from rain and snow; although when salt is mixed into sand, which is also applied to roadways, these piles of sand/salt mixtures are often left uncovered (author’s personal observations) The state of New Hampshire, in fact, has replaced a number of road salt-contaminated private wells found to have salt levels that exceeded 250 mg/L and where highway desalting impact has been proven In other communities it was found to be less expensive to connect impacted residences to nearby municipal drinking water distribution systems and remove them from their private wells RO technology is the only practical way to remove or reduce salt dissolved in water, and residential units can be quite costly, yet the technology is scalable, and large municipal operations are common and can be used for the desalination of seawater The technology involves the application of high pressure on one side of a device holding a membrane, causing mainly water molecules and some sodium and chloride ions to permeate the membrane, retaining most of the salt and for that matter most every other particle on the high-pressure side One problem with RO however is that the water from the higher-pressure side of the membrane is usually very high in salt concentration and must be disposed of locally, usually in a sanitary sewer or septic system on the property or in some cases allowed to evaporate in surface ponds Even small household systems that produce from 10 to 50 L of potable water a day produce a fair amount, up to 10 times the volume of useful water, of effluent that has to be disposed of For large municipal RO systems, deep well injection may be favorable, and for seawater desalination, of course direct discharge back into the sea is the way to minimize costs Electrical power consumption for water carrying a salt load of between 600 and 700 mg/L would require around 1.4 kWh/1000 gal or 0.37 kWh/1000 L Desalination of 35,000 mg/L dissolved solids seawater requires perhaps 7–10 times this amount of energy per unit of potable water produced [2] Membrane replacements also have to be considered since membrane fouling may at times occur and small household units may incur annual costs of between $100 and $200 Salt levels of rivers used extensively for agriculture are found to increase as fertilizers dissolve into irrigation waters and as water evaporates naturally on the way to the sea Although measuring the concentration of NaCl in water can be done, it is usually inferred using a simple electronic device known as a conductivity meter rather than carrying out wet chemical analyses Chloride anions can of course be determined by titration using a standard silver nitrate solution and potassium chromate indicator, which gives a red-colored silver chromate precipitate as soon as all of the chloride is consumed by the silver ions forming insoluble AgCl, the so-called end point of the titration Chloride-specific ion electrodes are also available but are subject to interferences and are used in conjunction with a standard pH meter Sodium ions can be determined analytically using a selective sodium ion electrode coupled to a standard pH meter It is true that the electrode does not measure concentration but activity of the ion, which is defined as at infinite dilution Usually salt and the term total dissolved ions (TDI) are used synonymously since in most cases (but not always) TDI is mostly salt (NaCl), and since ions can carry current, one usually measures TDI using a conductivity meter The basic unit is called an inverse-ohm/cm or mho/cm also called siemen (Si) Normally we work with values of one thousandth (milli-) or one millionths (micro-) of it for natural waters (1000 millimhos and 1,000,000 micromhos) Good potable water and freshwater streams have conductivities between 20 and 1500 μSi A solution of 0.01 M (584 mg/L) NaCl would produce a reading of 1156 μSi/cm Commercial meters for accurate measurements are available for around $350, but much cheaper less accurate units can be purchased for around $60 Water Supply and Public Health and Safety 565 29.5.5  Heavy Metals in Potable Water Plating operations in industrialized nations in the past have liberated huge quantities of chromium, silver, and copper, and other processes have liberated mercury much of which can now be found in the sediments of the rivers and lakes into which they were discharged, even accumulating in benthic sediments offshore as the rivers deliver their bounty to the seas Naturally occurring arsenic is found worldwide in two predominant forms in water, as the more toxic arsenite anion (AsO3−3) and the less toxic arsenate anion (AsO4−3) In Massachusetts, Reitzel [21] identified arsenic in deep rock wells, and although the origin of that arsenic was originally thought to be the result of arsenic from nonnatural sources leaching into the well water, only recently has the US Geological Survey provided evidence that the arsenic source is in fact the natural bedrock in an area that bisects the state via a fault that runs north–south through the state The US Environmental Protection Agency (USEPA) has recently reduced the maximal contaminant level or MCL from 50 to 10 μg/L Of special concern is that arsenic is known to cause a variety of serious diseases including several kinds of cancer, and even at the lower MCL it is thought to possibly contribute to an increased cancer incidence, but it is not sensible to legislate a level of “0,” which would be impossible for many water utilities to meet Many Third World countries also are plagued by groundwater arsenic including Bangladesh where perhaps as many as 20% of its population is threatened by high levels of this metal The need for expensive treatment technologies as well as the expense of analytical testing for the metal makes those remediation methods difficult to implement in developing countries Bangladesh also has the problem of the bioconcentration of arsenic, which in groundwater is used for irrigation The arsenate anion is often mistaken for phosphate by the transport systems of roots, and in fact the arsenate in irrigation water becomes part of the crop, which is then consumed by humans who then integrate the anion into their body tissues putting them at increased risk for its adverse health effects [16] 29.6  Municipal Water Treatment 29.6.1  General Issues No drinking water source should be assumed to be completely safe, especially those that serve large numbers of people, which we term public drinking water systems, and these systems use various methods of water treatment to provide safe drinking water for their communities Generally, a municipal water treatment plant employs several processes in series beginning with coagulation and flocculation of the incoming raw water using alum or ferric chloride to form a precipitate, followed by sedimentation to remove the floc and any other incoming particulate matter Coagulants are relatively inexpensive cationic salts that react with negatively charged particles forming larger particles called floc, which can be more easily removed when this water mass is passed through a sand, gravel, or charcoal filter Bacterial populations are usually reduced by around 90% using this form of technology, and it is a proven method for removal of the human pathogen protists C parvum and G lamblia, and even arsenic can be removed to below its maximum contaminant level of 10 μg/L C parvum is an intracellular parasite that infects cells of the bowel, and the pathogenicity of G lamblia occurs because this organism that also infects the bowel does so by attaching to the outside of cells preventing water reabsorption Some water sources prove difficult to manage by more traditional technologies and require state-of-the-art filtration technologies such as membrane microfiltration, RO, and adsorption Filtered water is then passed into a large tank where a chemical disinfectant is added After a period of time (known as the contract period) to insure that the chemicals have inactivated pathogens, the water is released into the distribution system for delivery to the consumers Disinfection kills or inactivates viruses and bacteria that are potentially harmful, but the process is not designed to provide sterile water and some bacteria can escape unharmed Typical disinfectants are gaseous chlorine (Cl 2), calcium or sodium hypochlorite (CaOCl and NaOCl, respectively), and 566 Handbook of Engineering Hydrology: Environmental Hydrology and Water Management ozone (O3), which must be produced on-site (in situ) using electrical discharge in a pure oxygen environment, but other disinfectant chemicals may be chosen for specific reasons The USEPA’s Public Drinking Water Systems web page (http://water.epa.gov/drink/) discusses water treatment strategies and lists the 90+ contaminants EPA regulates and why (http://water.epa.gov/drink/contaminants/ index.cfm) Somewhat controversial is the use of sodium fluoride in drinking water to prevent tooth decay in children, which introduces not only fluoride but some sodium into drinking water as it leaves the treatment plant Fluorosis or the mottling of teeth is often noted in children taking in excessive amounts of fluoride The recommended level of total fluoride is mg/L 29.6.2  Coagulation and Filtration Coagulation using alum and ferric chloride is used effectively for the reduction or removal of turbidity, organic matter, color, and even arsenic Alum (Al2[SO4]·18H2O and ferric chloride (FeCl3) are two examples of chemicals, which when added to raw drinking water form the precipitates aluminum hydroxide (Al[OH]3) and ferric hydroxide (Fe[OH]3), respectively After formation, the hydroxides react with negatively charged colloidal material in the water forming a floc, which is removed by rapid sand or gravel filtration The precipitates are prevented from travelling through the filter and accumulate on the surface, and at some point the precipitates must be removed from the top of the filter by reversing the flow of water (backwashing), and the resulting slurry of water and precipitates must be disposed of in a municipal sewer system Alternative chemicals include the inorganic polymer aluminum chlorohydrate and even diatomaceous earth as a filter aid 29.6.3  Water Disinfection Filtered water is then subject to chemical disinfection using chlorine gas (mostly in North America) and ozone (mostly in Europe) The effectiveness of a disinfectant is quantified by its ability to inactivate a population of bacteria by a factor of 10 (90% reduction in number) in a certain period of time, and this is called the log inactivation, defined as Log inactivation = Log No Nt (29.1) where No is the initial (influent) concentration of viable microorganisms (actually quantified as colonies growing on a specific medium under certain growth conditions) in raw water Nt is the concentration of surviving microorganisms, and log is to base 10 29.6.3.1  Chlorine and Hypochlorite Chlorine gas has been used as a disinfectant for decades It has the benefit of inactivating pathogens and providing what is called a “residual” as water travels through the pipes to the consumers at the very end of the distribution system Residual chlorine is important should pathogens survive the initial burst of chemical at the chlorinator or if pathogens are introduced inadvertently within the system via a temporary cross-connection Pathogens could survive the initial high concentration of chlorine, for example, if they were integrated in sediment that escaped filtration and some communities only rely on chlorination and not filter raw water Chlorine does react with a variety of natural chemicals found in raw water including organic matter and free ammonia and amines This loss of chlorine is called chlorine demand, which removes chlorine that would have been the disinfectant, and as a result additional chlorine must be added to make up for this loss Reaction of chlorine with organic matter forms trihalomethanes, thought to be carcinogens, and therefore it is necessary to balance the total chlorine added 567 Water Supply and Public Health and Safety with THM produced The active species for chlorine disinfection is free hypochlorous acid (HOCl) formed when chlorine gas reacts with water: Cl + H2O → HOCl + HCl (29.2) and HClO is a stronger oxidant than chlorine gas or the anion of HOCl, hypochlorite (OCl−) under standard conditions with an Eo = +1.63 V Hypochlorous acid is a weak acid with a pKa of 7.5 at 20°C thus when the pH = pKa 50% of the acid is in the free acid while the other half is in the anion hypochlorite form A lower pH, such as a pH of 6.5 would result in 90% free hypochlorous acid and 10% the disinfectant of lesser capability, the hypochlorite anion The mode of action of chlorine was contentious until 1981 when it was reported that cellular inactivation precedes the loss of respiration in bacterial cells capable of respiring, which failed to divide after exposure to HOCl [1] It is important to note that cell inactivation is dependent upon many factors including the presence of organic chemicals and various types of sediment in the water, which can react quickly with and thus deplete the HOCl concentration, the temperature of the water, the pH, and the time in which the bacteria are in the presence of HOCl, also called the contact time Reducing the pathogen population by 90% at a particular concentration of disinfectant in mg/L (a factor of 10) multiplied by the contact time (in minutes) needed for such inactivation is called the CT value (concentration X time in minutes) Table 29.1 shows the CT values for the indicator organism E coli and for cysts of the enteric pathogen G lamblia and viruses using four different disinfectants at 5° and 20° Chloramine is produced when Cl reacts with ammonia (NH3) in water to produce monochloramine (NH 2Cl), which as seen in Table 29.1 is really a poor disinfectant for any of the organisms listed On the other hand, chlorine dioxide (ClO2) and ozone (O3) have excellent disinfection capability Most people today think that ammonia addition to produce chloramines in drinking water was done to provide a residual (the chloramine molecule) for disinfection of inadvertent entry of pathogens in the distribution systems such as those caused by cross-connections However, chloramines really had nothing to with disinfection but with aesthetics When chlorine was added to water entering a distribution system in the early 1900s, the disinfectant reacted rapidly with any phenols, chemicals that were rampantly discharged as wastes from industrial processes that were indeed present Ammonia addition at the intakes forms chloramines rather than chlorophenols, which present medicinal tastes to the water and in the past resulted in complaints by consumers Table 29.1  Comparison of CT Values for 90% Inactivation of Microorganisms at 5°C and 20°C Organism E coli bacteria Viruses G lamblia cysts Free Chlorine (Cl2) (pH 6–7) Chloramines (NH2Cl) (pH 8–9) Chlorine Dioxide (ClO2) (pH 6–7) Ozone (O3) (pH 6–7) 0.034–0.05 2.0 at 5° 1.0 at 20° 35–50 at 5° 15–21 at 20° 95–180 857 at 5° 321 at 20° 1470 at 5° 735 at 20° 0.4–0.75 2.8 at 5° 1.0 at 20° 17 at 5° 10 at 20° 0.02 0.3 at 5° 0.125 at 20° 0.62 at 5° 0.24 at 20° Source: http://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/escherichia_coli/treatmenttraitement-eng.php Note: Guidance Manual for Compliance with the Filtration and Disinfection Requirements for Public Water Sources [25] and Health Canada Guidelines for Canadian Drinking Water Quality: Guideline Technical Document E coli Federal-Provincial-Territorial Committee on Drinking Water of the Federal-Provincial-Territorial Committee on Health and the Environment Health Canada Ottawa, Ontario February 2006 CT = concentration of disinfectant in mg/L multiplied by time in minutes required for one log (90%) inactivation 568 Handbook of Engineering Hydrology: Environmental Hydrology and Water Management Addition of ammonia with the formation of chloramines reduced such complaints but resulted in water of questionable public health safety [17] Chlorine dioxide can be produced in situ by the reaction of sodium chlorite and chlorine forming the gas ClO2 This disinfectant has a number of disadvantages, especially its cost, which is from to 10 times that for chlorine gas, and ozone is still better for recalcitrant pathogens like giardia cysts as seen in Table 29.1 29.6.3.2  Ozone Ozone must also be generated on-site and involves the discharge of a high voltage between two electrodes in an atmosphere of pure oxygen The O2 molecule dissociates under those conditions and the resulting atomic oxygen (O) reacts with other oxygen molecules forming ozone (O3) Ozone serves as an excellent disinfectant as shown in Table 29.2, but its cost is 2–3 times that for chlorine gas, and it leaves no residual in the distribution system as its lifetime is short Chlorine still must be added subsequently to provide that residual disinfectant An ozone/chlorine combination is used widely in Europe but only rarely in the United States One notable exception in the United States is the Massachusetts Water Resources Authority, which began disinfection using ozone at its treatment plant located 25 km from downtown Boston in 2005, adding chloramine for residual protection In this case, treated water travels a long distance through an underground tunnel before reaching the city center, and although the CT for chloramines is large, so is the time needed to deliver water to the 2.2 million residents in 44 cities and towns that form the authority 29.6.3.3  Ultraviolet Light Ultraviolet (UV) light has been used for disinfection for industrial purposes for decades High-quality water used in the electronics, medical, and biotechnology sectors usually places a UV device at the back end of their processes to insure that there is minimal likelihood of survival of any pathogen that will be used in product manufacture UV light kills organisms by causing a reaction of adjacent thymine bases on the organism’s DNA (its genome) forming what is known as thymine–thymine dimers If enough of these dimers form in the DNA, the molecule cannot replicate and neither then can the organism UV lamps need a quartz window since glass absorbs light of those wavelengths and works by high-voltage ionization of mercury atoms in the vapor inside the bulb, which emit UV light when the electrons return to their ground state The use of UV for inactivation of both giardia and cryptosporidium spp will be an important technology for New Yorkers once the system installed on the new Croton Aqueduct [24,25] is in operation On a more personal scale, it is common for visitors from the United States who visit, study, and work in countries that cannot provide safe drinking water to their population often use the new commercial battery-operated UV water purifiers to provide safer drinking water for themselves and their families and colleagues (as per the author’s discussions with scientist-colleagues who regularly visit Brazil) Table 29.2  Disinfection By-Products Regulated by the USEPA Disinfectant By-Product Trihalomethanes—chloroform, bromodichloromethane, dibromochloromethane, and bromoform Haloacetic acids—monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid Bromates Chlorite Causes Reactions of chlorine with organic matter in source water Reactions of chlorine with organic and inorganic matter in source water Reactions of ozone with bromides in source water Reaction of ClO2 Source: http://www.epa.gov/enviro/html/icr/gloss_dbp.html Maximum Contaminant Level 80 μg/L 60 μg/L 10 μg/L μg/L Water Supply and Public Health and Safety 569 29.6.3.4  Disinfection By-Products When certain disinfectants react with bromide or natural organic matter (i.e., decaying vegetation) present in the source water, harmful by-products can be formed Disinfection by-products that are regulated by the USEPA include trihalomethanes, haloacetic acids, bromate, and chlorite Table 29.2 lists the four classes of disinfection by-products and how they are formed at the USEPA maximum contaminant levels that are permitted Another parasite of great concern is the enteric parasite C parvum, a pathogen that infects the cells of the lumen of the bowl and is present in most cattle herds, especially in the newborn calf population and in humans causes serious diarrhea and dehydration This pathogen was associated with a serious public health emergency in Milwaukee (WI) in 1993, where Lake Michigan serves as source water Thousands of residents most likely contracted the disease and many theories for the outbreak have been offered, but none has been confirmed In a laboratory study challenging mice with 10,000 oocytes of C parvum, Peeters et al [20] showed that ozone at 1.11 mg ozone/L was required to inactivate all oocytes in a contact period of six but 0.4 mg/L ClO2 per liter reduced but did not inactivate all oocytes Chlorine is not considered a suitable method for disinfection of C parvum in drinking water source water Those who are immunologically compromised have difficulty fighting an infection How we know that water directed to consumers is free of pathogens? It is difficult to actually test for the presence of viable viruses and protozoans such as giardia or cryptosporidium species For this reason it is customary to use an indicator of the presence of pathogens and the bacterium E coli, present in most warm-blooded animals, has been chosen to serve in this capacity In the early 1900s, the presence of this bacterium in water was determined in a cumbersome laboratory test known as the most probable number test, which measured gas produced in a test tube when a volume of water was added to a fermentation broth that supported the growth of E coli and the evolution of gas as a metabolic product A simpler method was developed that used a specific medium originally developed in 1904 but improved at the Lawrence Experiment Station in Lawrence, Massachusetts (United States), for the group of lactose-fermenting bacteria that we call “coliforms,” which have their origin in both the gut tract of warm-blooded animals and in decaying organic matter The bacteriological medium became known as mEndo-LES, and coliforms are identified after overnight incubation by a green metallic sheen on colony surfaces, the result of small crystals of basic fuchsin forming on those surfaces The USEPA redefined the medium in 2002 and called the new test “Method 1604” [26] This method utilizes two chromogenic dyes to identify total coliforms and especially E coli in the sample In the new method, a 100 mL sample of aseptically collected water is passed through a 0.45 μm membrane filter, and the filter transferred to a suitable culture dish to which was added mL of the growth medium and incubated at 35° for 24 h Total coliforms are viewed under UV light (366 nm), and E coli colonies appear blue under room light In the United States, the EPA has developed the standard for E coli, and coliforms found as “0” and if found the same sampling site must be retested No more than 5% of all samples tested must have evidence of these organisms, which is clear evidence that these viable organisms have survived disinfection The consumer of the water provided by the municipality should feel confident that he or she is obtaining a safe and aesthetically appealing product so it is imperative for the water manager to maintain vigilance over the entire system, testing both source water and water from sampling sites within the distribution system for various parameters that are reliable indicators of water quality Should the community begin to experience some form of enteric disease outbreak as recorded in medical facilities and clinics, the water manager working with local public health personnel should try to seek answers that may implicate or hopefully demonstrate that drinking water is not at fault 29.6.4  Special Case for Developing Countries Special attention must be paid to drinking water available to households in the developing world since well-protected supplies coupled with efficient distribution systems employing adequate water treatment to insure safe water for consumers are often not possible In the developing world, unsafe drinking 570 Handbook of Engineering Hydrology: Environmental Hydrology and Water Management Table 29.3  Household (Point-of-Use) Water Treatment and Storage Options for Developing Countries Method of Water Treatment Log Bacterial Reduction Cost per Annum per Person Comments Free chlorine (hypochlorite) Combined free chlorine and coagulation (alum) SODIS $0.66 $4.95 Cost and availability issues Cost and availability issues $0.63 Porous ceramic filter $3.03 Slow biosand filter $60 (one time cost) Efficacy dependent on many factors such as oxygenation, time allowed for treatment and use of non-SODIS water Products are variable as to pore size, tortuosity of channels, and chemical treatment (Ag impregnation) High compliance requires maintenance, posttreatment disinfection recommended Source: Sobsey, M.D et al., Environ Sci Technol., 42, 4261, 2008; UNICEF, Promotion of household water treatment and safe storage in UNICEF water programmes, http://www.unicef.org/wash/files/Scaling_up_HWTS_ Jan_25th_with_comments.pdf, 2008 (Accessed June 20, 2012) Note: All methods require a learning component by a trained educator water coupled with poor sanitation and hygiene contribute to perhaps as many as billion cases of diarrheal disease annually, causing more than 1.5 million deaths, mostly among children under years of age [29] Still there are 1.1 billion people in the world without access to safe drinking water [30] Circumstances often require members of a family to seek water from distant sources where its quality is usually not certain This water must be returned to the home where it should be subject to some form of household water treatment and storage (HWTS) to insure its potability and safety In fact, a recent study did indeed show that HWTS was effective in preventing diarrheal disease [6] The same kinds of strategies used in the developed world on a large municipal scale to protect the safety of drinking water are also scalable downwards to the household level as shown in Table 29.3 Clasen [6] stated that the use of point-of-use household treatment was more effective than having to rely on improved wells and communal standpipes Boiling of water is not recommended because fuel, usually wood, is already in short supply in many of these same areas of the world Of course there are issues related to each of these methods that can compromise the method For example, it is common to fail to leave bottles used for solar disinfection (SODIS) in the sunlight for a sufficient time, and each method requires an “in-service” training session by a trained educator In most countries, households can rely on obtaining the initial hardware for their selected water treatment method as a donation or a subsidy from a governmental or nongovernmental organization (NGO) Figure 29.2 is a schematic of a biosand (slow sand) filter to remove sediment and around 90% (1 log removal) of bacteria that are poured with water into the top of the device The top 1–2 cm of biofilm takes around a month to develop once use is initiated, and the next 10 cm of the filter provides the active biological zone where incoming bacteria are removed by competition with other organisms on the biofilm that forms on the sand grains Disinfection using SODIS or chlorination is still recommended since only one log removal is normal for this kind of system 29.7  Case Studies: Potable Water Quality and Safety Issues in Eastern Massachusetts 29.7.1  Description of the System This author has had the opportunity to directly witness a number of events and instances that could testify to the attitude that society in general had about its lack of concern for its potable water supplies during that period of history One good reason that well-protected upland supplies were important 571 Water Supply and Public Health and Safety Siphoned unfiltered water Sand layer with biofilm to a depth of 25 cm Cap—when closed protects against contamination Diffuser—protects sand layer and biofilm against agitation from incoming unfiltered water Filtered water out (one log decrease in microbial contamination) Outlet—may be inside or outside filter body Gravel base (holds sand in place) Figure 29.2  Schematic of a biosand (slow sand) filter in the eastern United States was that for decades industry required a free water supply for many of its functions, for water power certainly, but especially for disposal of liquid waste materials In the city of Worcester (MA), the author joined with the city Departments of Public Health and Public Works and the City Manager’s office to form the Water Quality Resource Study Group of the Worcester Consortium for Higher Education The purpose of the study group was to tackle drinking water problems facing the city, which was served by several upland reservoirs and two wells in addition to a connection to a reservoir serving Greater Boston Twenty-four million gallons (91 million liters) are provided on average daily to about 200,000 people delivered through almost 600 miles (780 km) of piping Until a modern treatment plant was constructed during the 1990s, chlorination was the sole disinfection technology 29.7.2  Infectious Hepatitis Outbreak In 1969–1970, the city of Worcester experienced a serious outbreak of infectious hepatitis (hepatitis A), an enteric viral disease passed via the fecal–oral route The outbreak made national news and was featured in Life Magazine, and the scientific findings were later reported in peer-reviewed publications [8,18] Briefly, many members of the Holy Cross College football team (American football—not what in the United States is called soccer) experienced the disease due to a point source introduction of a sizable virus load when several seemingly unrelated situations occurred That period of the late summer was very hot in the city, and children from a nearby multifamily home discovered that they could obtain relief from the heat by scaling a fence onto college property and bathing in the small pools created by the irrigation system in the practice field It appears that some of the irrigation system valves were left slightly open to the city water distribution system A fire in a retail property perhaps a km or two to the west was fought using water forced by pumper trucks capable of delivering 200,000 L of water per hour, but to this, water must be drawn through the piping from all directions including the water in the standing pools on the Holy Cross college campus, which were inadvertently left open creating what is known as a “cross-connection.” It appears that one or more of the children using the pools had active hepatitis A, and instead of returning home to find relief, the child simply defecated near or in the pool This highly polluted water was drawn into the distribution system of the college during the fire, and when the football team, tired and hot, entered a maintenance shed near the field to satisfy their thirst, they had no idea that they were consuming water that would sicken most of the team and effectively end 572 Handbook of Engineering Hydrology: Environmental Hydrology and Water Management the football season for the college A backflow preventer most likely would have prevented this kind of event During that same year, the city of Worcester itself experienced an outbreak of the same disease, the incidence of which was shown to correlate not only with socioeconomic conditions of city inhabitants but with certain water and sewer system parameters [15], especially water system type (high- or low-pressure system) and water and sewer pipe ages 29.7.3  Disinfection System Breakdown Another instance was an outbreak of diarrheal disease in Worcester that was traced to one of the wells that were put into service in the east side of the city during a period of drought In this case the Coal Mine Brook well rated at 2.9 million gallons of water per day supplemented the 40 million gallons of water used daily for domestic, commercial, and industrial purposes Many adult students taking a weekend photography course at a hotel served by this well became sickened, initially blaming the hotel’s food preparation However, further investigations showed that there was possible negligence by one city employee whose job was to ascertain that the liquid chlorine (as sodium hypochlorite) feed that was metered into the water pumped directly into the city distribution system was operating improperly The disinfectant was contained in a tank and the tank was positioned onto a scale, and the employee was supposed to check to insure that the sodium hypochlorite was being metered out properly Although he clearly noted in his mind that the pump had apparently malfunctioned as none of the hypochlorite solution had left the tank, he failed to report the incident at the time and as a result presumably contaminated water entered the distribution system It was later found that nearby Coal Mine Brook was highly contaminated and that the distance between well and brook was insufficient to filter out harmful pathogens and the well was permanently taken off-line 29.7.4  Threats against a Water Supply Water supply managers have to contend with constant surveillance of the water they provide to consumers (or customers) to insure safety and public health Natural phenomena can create havoc such as when a lightning strike disabled a treatment process Such an event did occur in Worcester, MA, but an audible alarm in the chlorinator minimized the time required to react to the problem and make repairs However, from time to time human intervention can occur, such as a hazardous material or waste spill occurring in a watershed, especially if in proximity to the intake to a distribution system What might happen should a credible threat be made against a surface water supply since most are somewhat accessible to illegal entry by a determined person? Perhaps a minor example occurred on June 15, 2011, when a man was observed urinating in the Mt Tabor reservoir in Portland, OR, forcing the city to discard the entire 7.8 million gallons of drinking water to waste, an amount valued at about $36,000 including a $7,000 disposal fee for the water This event seems trivial and except for the psychological element of consuming water containing a trivial amount of urine, there was no scientific need to take such drastic actions No one seems to have minded the presences of birds and animals in the vicinity of this distribution reservoir as it was left open to nature in general until the incident discussed previously However, some issues must be dealt with employing utmost urgency In particular, one such incident that was quickly and quietly dealt with was one that today would be termed a case of “domestic terrorism.” One evening in the mid-1970s, the Water Quality Resource Study Group received a phone call from the assistant director of the Worcester Department of Public Health, and he remarked that we needed to come up with a plan immediately to deal with a threat to an unnamed public water supply in Massachusetts We were told that the Jackson Gang (actually known initially as the Sam Millville/ Jonathan Jackson Gang, changing its name to the United Freedom Front, a very small leftist prison reform group) had dumped cyanide into a drinking water source, and our services were requested to aid the Health Department in the dealing with the matter immediately The threat, allegedly by the Jackson Water Supply and Public Health and Safety 573 Gang, was taken seriously since it was their modus operandi to inform the public prior to carrying out an action, reducing the likelihood of civilian casualties A bottle of potassium cyanide from the university chemical stock room was picked up and brought to the Worcester Public Health Laboratory Once at the laboratory, a colleague at nearby Clark University known to be interested in environmental chemistry and who may have been able to help select an analytical procedure was called upon Surprisingly, that colleague had just purchased a new cyanide analytical tool, an Orion cyanide electrode, which although not as able to give a sensitivity as good as that of the Standard Methods chemical procedure, it would provide us with the speed needed to get our set of assays done Using the electrode was also not a method validated by any agency at the time for water analysis, but this was one of the special moments that demanded immediate action After standardizing the electrode, which used a pH/millivolt meter, cyanide levels were measured in raw water samples taken by state and municipal public health personnel at the intakes of many of the central Massachusetts reservoirs By the time all 22 samples were assayed at AM, no cyanide had been found, and it was learned that the state environmental laboratory in Lawrence had not yet even begun to carry out their assays, and they had to resort to the standard chemical assay, which had a long preparation time since they did not yet possess a cyanide electrode To the public’s knowledge, there was never a positive assay that could be directed at any single surface supply, but Mr Bernard Borci, the Public Health laboratory manager, who was very familiar with using cyanide in plating baths in the city, assured us that depending on how anyone might add a cyanide salt to cold reservoir water, it would take a rather long time for it even to dissolve Fortunately, the event was noted only on an inside page of the local newspaper the following day How a community might in fact react to such an event today is of course up for debate, but it is likely that a decision to minimize the possible consequences of such an event as was made then, by minimizing public attention of the issue would not be suitable today 29.8  Water Quality and Climate Change The climate of the world is changing It has been doing so in one way or another since the last glacial maximum around 23,500 years ago, but there are indicators that it is changing faster now than anytime in current human history A multitude of data all show temperature trends that are in the positive direction, and this phenomenon has been attributed to the accumulation of certain gasses emitted due to human activity It is not the purpose of this chapter to explain these changes but to assess the impact temperature rise will have on water quality and public health and safety associated with climate change Foster and Rahmstorf [12] examined five prominent time series of global temperature for the period 1979–2010, and all showed a temperature anomaly of from 0.141°C/decade to 0.175°C/decade No one really knows how climate change will affect drinking water security, but several studies point to those issues water managers will have to consider in the coming decades The most vulnerable people are those living in the developing world where access to safe drinking water and proper sanitation are important issues A water-stressed region is one where precipitation runoff has been determined to be less than 1000 m3 per person per year, and in 1995 it was estimated these areas were home to a population of 1.4 billion [7] Climate change may change the patterns of human immigration with cities such as Delhi (India) facing population increase that will bring the census to as many as 30 million and even today water must be imported from as far away as 300 km to satisfy needs of the people Computational models attempt to predict how climate change will affect precipitation patterns across large areas including continents, but none of these has yet been tested or can be One-sixth of the Earth’s population lives in areas dependent on meltwater from mountain glaciers and snowpack, and there is evidence that glacial retreats are in progress and that highest flow rates in catchments are in fact arriving earlier in the year as temperatures in the spring rise a little earlier than they once did exacerbating dry season water availability [5] Since we have based our water security planning activities on the historic record of drought and precipitation, water managers must now try at least to plan for the unexpected brought about by climate change Computational models based on past climate records help somewhat, but these models must be 574 Handbook of Engineering Hydrology: Environmental Hydrology and Water Management improved and new data sets as they are generated year by year used to fortify their results and providing a better look into the future Although the developed world has learned how to exploit virtually any water resource, there is still hope for many countries of the developing world since many resources are still untapped For example, only 4% of Africa’s groundwater resources are in current use, and the availability of engineering and hydrology competent human resources will be of great benefit It also may be wise to consider novel water storage technologies such as aquifer recharge when excess water is already or if it becomes available In Pima County, Arizona, some of the water delivered from the Colorado River 500 km away via an aqueduct known as the Central Arizona Project is allowed to infiltrate local aquifers for use during drought years in the likely event it be needed in the coming decades and that area is already using reclaimed municipal wastewater for irrigation and the greening of local golf courses and municipal parks A significant long-term temperature increase due to climate change with associated evaporation of the Colorado River as it winds its way southwestward is likely to lead to increased salinity of river water as it travels into Mexico, which could violate a treaty that specifies just how much salinity in river water is acceptable Climate scientists warn that increasing global temperatures will likely bring more intense and unpredictable climatic events such as harsher floods and droughts Analyzing 18 watersheds in the US Wolock and McCabe [27] compared two computational models, the Canadian Climate Model and the Hadley Climate Model for runoff, and neither was consistent with the other demonstrating the need for further research A decade and a half has passed since the 1997 publication of the American Water Works Association’s recommendations for water managers who will have to deal with problems associated with climate change issues in the future, but little more can be said about them since there is still very limited if any relevant experience [3] In other words, the increasing global temperatures that the world has in fact seen since the early 1970s have not yet done sufficient “damage” to allow anyone to be able to predict negative events with any certainly The “take-home message” from all of these studies is that water resources planning and related public health and safety issues should be considered during all phases of the planning process, just as is done now when water managers try to foresee and take preventative measures on a routine even daily basis Information technology allows water managers everywhere to communicate with one another and with personnel of other governmental personnel at all levels and in the end keep as vigilant as possible in hopes of averting a disaster should there be one in anyone’s future 29.9  Summary and Conclusions Drinking or potable water security refers to both safety and public health issues, which must be addressed in order for consumers to feel confident about their water supply Availability of safe drinking water is very site specific and ranges from many people in the developing world having to walk great distances from their home to obtain it and then to return to the home for drinking and food preparation, often on a daily basis, to others simply turning on a tap in their home for what seems an infinite supply and never having to worry about the matter Those who provide their own water usually from a well must be aware that there is usually no one to offer periodic inspection and analysis of their water and they themselves must insure its safety, and this usually involves a fee for a laboratory to perform proper analysis Many foreign governmental agencies and NGOs now provide financial and educational assistance for those in the developing world to help with the cost and setup of on-site point-of-use but simple treatment systems Cities and town that provide water to many residents and businesses have planning agencies, which maintain vigilance of the present water supply and distribution systems by assessing water quality and quantity and are also looking forward to insure both supply and quality for the future New technologies are used to obtain water from unlikely sources such as domestic wastewater and the oceans and seas of the world The immediate development of untapped groundwater supplies in Africa, for example, could solve many problems on that continent The most important issues however are for both those dealing with their own water supply and those working in municipal agencies who are in charge of water for masses of people, are to always be alert and aware of the sources of their raw water, and are Water Supply and Public Health and Safety 575 to be ready to react should something unexpected happen that might threaten the supply in some way Once lost, a water supply is difficult to replace To what seems to be too much to provide protection of a water supply is nonsense It is always better to error on the side of safety! References Albrich, J.M., McCarthy, C.A., and Hurst, J.K 1981 Biological reactivity of hypochlorous acid: Implications for microbicidal mechanisms of leukocyte myeloperoxidase Proc Natl Acad Sci USA 78: 210–214 Alexander, K.L 2008 Desal in the west: Opportunities and challenges Southwest Hydrology (March/ April), 7, 26–30 http://swhydro.arizona.edu/archive/V7_N2/feature6.pdf (accessed September 27, 2013) American Water Works Association (AWWA) 1997 Climate change and water resources: Committee report of the AWWA public advisory forum J Am Water Works Assoc 89: 107–110 Bartoshuk, L.M 1974 NaCl thresholds in man: Thresholds for water taste or NaCl taste? J Comp Physiolog Psychol 87: 310–325 Bates, B.C., Kundzewicz, Z.W, Wu, S., and Palutikof, P (eds.) 2008 Climate Change and Water Technical paper of the intergovernmental panel on climate change Geneva, Switzerland: IPCC Secretariat Clasen, T., Roberts, I., Rabie, T., Schmidt, W., and Cairncross, S 2006 Interventions to improve water quality for preventing infectious diarrhoea (a Cochrane Review) In: The Cochrane Library, Issue 3, Oxford, U.K.: Update Software Costello, A., Abbas, M., Allen, A et al 2008 Managing the health effects of climate change The Lancet 373: 1693–1733 Crusberg, T.C., Burke, W., Reynolds, J.T., Morse, L.J., Reilly, J., and Hoffman, A.H 1978 The reappearance of a classical epidemic of infectious hepatitis in Worcester, Massachusetts Am J Epidemiol 107: 545 Elimelech, M and Phillip, W.A 2011 The future of seawater desalination: Energy, technology and the environment Science 333: 712–717 10 English, P.W 1968 The origin and spread of qanats in the old world Proc Am Phil Soc 112: 170–181 11 Flint, A 1873 Relation of water to the propagation of fever Public Health 1: 164–172 12 Foster, G and Rahmstorf, S 2011 Global temperature evolution 1979–2010 Environ Res Lett 6: 044022 http://iopscience.iop.org/1748-9326/6/4/044022 (accessed June 20, 2012) 13 Fox, K.R 1995 Turbidity as it relates to waterborne disease outbreaks Presentation at M/DBP Information Exchange Cincinnati, OH: AWWA Whitepaper 14 Frontinus, S.J 1973 The Two Books on the Water Supply of the City of Rome, AD97, Translated by C Herschel, Boston, MA: New England Water Works Association 15 Hoffman, A.H., Crusberg, T.C., and Savilonis, B 1979 Statistical correlations between infectious hepatitis and water and sewerage system parameters Arch Env Health 34: 87–91 16 Lubin, J.H., Beane-Freeman, L.E., and Cantor, K.P 2007 Inorganic arsenic in drinking water: An evolving public health concern J Nat Can Inst 99: 906–907 17 McGuire, M.J 2008 Eight revolutions in the history of U.S drinking water disinfection J Am Water Works Assoc 98: 123–148 18 Morse, L.J, Bryan, J.A, and Hurley, J.P 1972 The Holy Cross College football team hepatitis outbreak J Am Med Assoc 219: 706–708 19 NADP 2007 National atmospheric deposition program archives http://nadp.sws.uiuc.edu/maplib/ archive/NTN/ (accessed June 20, 2012) 20 Peeters, J.E., Mazás, E.A., Masschelein, W.J., Villacort, W.J., de Maturana, I., and Debacker, E 1989 Effect of disinfection of drinking water with ozone or chlorine dioxide on survival of Cryptosporidium parvum oocysts Appl Environ Microbiol 55: 1519–1522 576 Handbook of Engineering Hydrology: Environmental Hydrology and Water Management 21 Reitzel, N.M 1984 Arsenic in rock wells in central Massachusetts In Crusberg, T.C., Cheetham, R.D and Hoffman, A.H (eds.) 1985 Water Quality and the Public Health, Proceeding of a Conference Worcester Consortium for Higher Education: Worcester, MA, pp 116–126 22 Sobsey, M.D., Stauber, C.E., Casanova, L.M., Brown, J.M., and Elliott, M.A 2008 Point of use household drinking water filtration: A practical, effective solution for providing sustained access to safe drinking water in the developing world Environ Sci Technol 42: 4261–4267 23 UNICEF 2008 Promotion of household water treatment and safe storage in UNICEF water programmes. http://www.unicef.org/wash/files/Scaling_up_HWTS_Jan_25th_with_comments.pdf (accessed June 20, 2012) 24 U.S Environmental Protection Agency 1996 Ultraviolet Light Disinfection Technology in Drinking Water Application—An Overview Washington, DC: Office of Water EPA/811-R-96-002 25 U.S Environmental Protection Agency 1999 EPA guidance manual: Alternative disinfectants and oxidants (Chapter 8) http://water.epa.gov/lawsregs/rulesregs/sdwa/mdbp/upload/2001_01_​ 12_mdbp_alter_chapt_8.pdf (accessed June 20, 2012) 26 U.S Environmental Protection Agency (Office of Water) 2002 Method 1604: Total coliform and Escherichia coli in water by membrane filtration using a simultaneous detection technique (MI medium) EPA 821-R-024, Washington, D.C http://www.epa.gov/microbes/documents/1604sp02 pdf (accessed September 26, 2013) 27 Wolock, D.M and McCabe, G.J 1999 Simulated effects of climate change on mean annual runoff in the conterminous United States [abstract], In Adams, D.B., ed., Proceedings of Specialty Conference on Potential Consequences of Climate Variability and Change to Water Resources of the United States, May 10–12, 1999, Atlanta, GA: American Water Resources Association, pp 161–164 28 World Health Organization (WHO) 2003 Emerging Issues in Water and Infectious Diseases Geneva, Switzerland: World Health Organization 29 World Health Organization (WHO) 2005 Progress towards the millennium development goals, 1990–2005 http://unstats/un.org/unsd/mi/goals_2005/goal_4.pdf on 15 November 2005 (accessed June 20, 2012) 30 World Health Organization (WHO) 2006 Mortality Country Fact Sheet 2006: Ethiopia Geneva, Switzerland: World Health Organization Water Science and Engineering While most books examine only the classical aspects of hydrology, this threevolume set covers multiple aspects of hydrology and includes contributions from experts comprising more than 30 countries It examines new approaches, addresses growing concerns about hydrological and ecological connectivity, and considers the worldwide impact of climate change It also provides updated material on hydrological science and engineering, discussing recent developments as well as classic approaches Published in three books, Fundamentals and Applications; Modeling, Climate Change, and Variability; and Environmental Hydrology and Water Management, the entire set consists of 87 chapters and contains 29 chapters in each book The chapters in this book contain information on • • • • • •  he anthropocenic aquifer, groundwater vulnerability, and hydrofracturing T and environmental problems Disinfection of water, environmental engineering for water and sanitation systems, environmental nanotechnology, modeling of wetland systems, nonpoint source and water quality modeling, water pollution control using low-cost natural wastes, and water supply and public health and safety Environmental flows, river managed system for flood defense, stormwater modeling and management, tourism and river hydrology, and transboundary river basin management The historical development of wastewater management, sediment pollution, and sustainable wastewater treatment Water governance, scarcity, and security The formation of ecological risk on plain reservoirs, modification in hydrological cycle, sustainable development in integrated water resources management, transboundary water resource management, and more Students, practitioners, policy makers, consultants, and researchers can benefit from the use of this text Environmental Hydrology and Water Management Environmental Hydrology and Water Management Eslamian Handbook of Engineering Hydrology Handbook of Engineering Hydrology K15218 ISBN: 978-1-4665-5249-4 90000 781466 552494 K15218_COVER_final.indd 2/3/14 12:58 PM