Water Centric Sustainable Communities E-Book

Vladimir Novotny

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 1095

Veröffentlichungsjahr: 2010

Beschreibung

The current literature compartmentalizes the complex issue of water and wastewater into its discrete components; technology, planning, policy, construction, economics, etc.  Considered from the perspective of sustainability, however, water in the urban environment must be approached as a single resource that can be continuously reused and recycled.  This book will be the first to capture all of the current work on this idea in a single, integrated, plan for designing the water-centric cities of the future.  From new construction to the retrofitting of existing systems, this book presents the case for a new urban relationship to water, one with a more sustainable connection to the environment and the hydrological cycle.  Through case studies of successfully planned and built systems around the world, the book will educate the reader about the need for a new approach to urban water management, and make the case that these changes are not only possible but imperative.

Leseprobe

Table of Contents

Title Page

Copyright Page

PREFACE

Acknowledgments

I - HISTORIC PARADIGMS OF URBAN WATER/STORMWATER/ WASTEWATER MANAGEMENT AND ...

I.1 INTRODUCTION

I.2 HISTORIC PARADIGMS: FROM ANCIENT CITIES TO THE 20TH CENTURY

I.3 DRIVERS FOR CHANGE TOWARDS SUSTAINABILITY

1.4 THE 21ST CENTURY AND BEYOND

REFERENCES

II - URBAN SUSTAINABILITY CONCEPTS

II.1 THE VISION OF SUSTAINABILITY

II.2 THE SUSTAINABILITY CONCEPT AND DEFINITIONS

II.3 TOWARDS THE FIFTH PARADIGM OF SUSTAINABILITY

II.4 CITIES OF THE FUTURE—WATER CENTRIC ECOCITIES

II.5 ECOCITY/ECOVILLAGE CONCEPTS

REFERENCES

III - PLANNING AND DESIGN FOR SUSTAINABLE AND RESILIENT CITIES: THEORIES, ...

III.1 INTRODUCTION

III.2 ECOSYSTEM SERVICES

III.3 PLANNING FOR RESILIENT AND SUSTAINABLE CITIES

III.4 BEST PRACTICES FOR GREEN INFRASTRUCTURE

III.5 DISCUSSION

REFERENCES

IV - STORMWATER POLLUTION ABATEMENT AND FLOOD CONTROL—STORMWATER AS A RESOURCE

IV.1 URBAN STORMWATER—A PROBLEM OR AN ASSET?

IV.2 BEST MANAGEMENT PRACTICES TO CONTROL URBAN RUNOFF FOR REUSE

REFERENCES

V - WATER DEMAND AND CONSERVATION

V.1 WATER USE

V.2 WATER CONSERVATION

V.3 SUBSTITUTE AND SUPPLEMENTAL WATER SOURCES

REFERENCES

VI - WATER RECLAMATION AND REUSE

VI.1 INTRODUCTION

VI.2 WATER RECLAMATION AND REUSE

VI.3 WATER QUALITY GOALS AND LIMITS FOR SELECTING TECHNOLOGIES

REFERENCES

VII - TREATMENT AND RESOURCE RECOVERY UNIT PROCESSES

VII.1 BRIEF DESCRIPTION OF TRADITIONAL WATER AND RESOURCE RECLAMATION TECHNOLOGIES

VII.2 SLUDGE HANDLING AND RESOURCE RECOVERY

VII.3 NUTRIENT RECOVERY

VII.4 MEMBRANE FILTRATION AND REVERSE OSMOSIS

Ⅶ.5 DISINFECTION

Ⅶ.6 ENERGY AND GHG EMISSION ISSUES IN WATER RECLAMATION PLANTS

Ⅶ.7 EVALUATION AND SELECTION OF DECENTRALIZED WATER RECLAMATION TECHNOLOGIES

REFERENCES

VIII - ENERGY AND URBAN WATER SYSTEMS—TOWARDS NET ZERO CARBON FOOTPRINT

VIII.1 INTERCONNECTION OF WATER AND ENERGY

VIII.2 ENERGY CONSERVATION IN BUILDINGS AND ECOBLOCKS

VIII.3 ENERGY FROM RENEWABLE SOURCES

VIII.4 ENERGY FROM USED WATER AND WASTE ORGANIC SOLIDS

VIII.5 DIRECT ELECTRIC ENERGY PRODUCTION FROM BIOGAS AND USED WATER

VIII.6 SUMMARY AND A LOOK INTO THE FUTURE

VIII.7 OVERALL ENERGY OUTLOOK—ANTICIPATING THE FUTURE

REFERENCES

IX - RESTORING URBAN STREAMS

IX.1 INTRODUCTION

IX.2 ADVERSE IMPACTS OF URBANIZATION TO BE REMEDIED

IX.3 WATER BODY RESTORATION IN THE CONTEXT OF FUTURE WATER CENTRIC (ECO)CITIES

IX.4 SUMMARY AND CONCLUSIONS

REFERENCES

X - PLANNING AND MANAGEMENT OF SUSTAINABLE FUTURE COMMUNITIES

X.1 INTEGRATED PLANNING AND MANAGEMENT

X.2 URBAN PLANNING

X.3 INTEGRATED RESOURCES MANAGEMENT (IRM)

X.4 CLUSTERS AND ECOBLOCKS—DISTRIBUTED SYSTEMS

X.5 SYSTEM ANALYSIS AND MODELING OF SUSTAINABLE CITIES

X.6 INSTITUTIONS

REFERENCES

XI - ECOCITIES: EVALUATION AND SYNTHESIS

XI.1 INTRODUCTION

XI.2 CASE STUDIES

XI.3 BRIEF SUMMARY

REFERENCES

APPENDIX

INDEX

Cover picture credit Malena Karlsson, GlashusETT, Stockholm (Sweden)

This book is printed on acid-free paper.

Copyright © 2010 by John Wiley & Sons, Inc. All rights reserved

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Published simultaneously in Canada

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Library of Congress Cataloging-in-Publication Data:

Novotny, Vladimir, 1938-

Water centric sustainable communities: planning, retrofitting,and building the next urban environment / Vladimir Novotny, John Ahern, Paul Brown.

p. cm.

Includes index.

ISBN 978-0-470-47608-6 (cloth); ISBN 978-0-470-64282-5 (ebk); ISBN 978-0-470-64283-2 (ebk); ISBN 978-0-470-64284-9 (ebk); ISBN 978-0-470-94996-2 (ebk); ISBN 978-0-470-95169-9 (ebk); ISBN 978-0-470-95193-4 (ebk)

1. Municipal water supply. 2. Water resources development. 3. Sustainable development. 4. Urban runoff - Management. 5. Watershed management. I. Ahern, John, 1949- II. Brown, Paul, 1944- III. Title.

TD346.N68 2010

628.109173’2 - dc22 2010005121

PREFACE

There is a growing belief among engineers, planners, and scientists that the function and purpose of our urban water infrastructure needs a radical redefinition. The conceptual models employed in most cities have not changed much since Roman times. They comprise rapid-conveyance piped systems that keep land relatively dry most of the time, provide a supply of potable water, and use water to carry away human and industrial wastes for disposal. Managing water quality, both for potable and disposal purposes, is generally accomplished by removing contaminants at the beginning or end of the pipe. Periodic flooding is controlled with additional structural barriers that rapidly drain urbanized areas towards downstream locations. Importantly, these systems have always been integrated into the built environment of buildings and streets—and largely taken for granted in terms of their functional role.

The calls for “Water centric sustainable communities,” “Cities of the Future,” “Sustainable Future Communities” may sound today more like futuristic dreams than a potential reality. But the future is always an extension of history and change is forced, and guided, by new incremental discoveries and stresses. Now is the time when serious stresses such as population increase and migration into cities and global climatic changes have emerged as serious issues of global concern. Infrastructure in old cities has deteriorated, and the U.S. is beginning to understand, and confront, the consequences of suburban sprawl in terms of infrastructure requirements, energy costs and pollution. The time has come to look for and implement new concepts for urban planning and design.

Historically, cities started as walled villages or settlements on or near a water source. Without water, life in the cities could not be sustained. Water also provides for cleaning and hygiene, transportation, irrigation of crops and gardens, defense, and transportation. In the “Cities of the Future” context, one has to look to, and learn from, the past about the importance of water in cities. Past successes can provide inspiration and continuity for the future and also can reveal what happens when water management is abused and/or water is lost. The first integrated, modern water/used water and stormwater management system can be dated to the second millennium B.C. in the Minoan civilization on the Mediterranean island of Crete. The Minoan cities had stone paved roads and offered water and sewage disposal to the upper-class. Water was brought to the cities from wells and clean mountain waters by aqueducts, rainwater was collected and stored in underground cisterns, and water was distributed to the fountains and upper class villas by advanced water systems using clay pipes. There is archeological evidence of Minoan use of flushed bathrooms. Wastewater and storm water were collected in sanitary and storm sewers. Many of these technologies were then adopted by Greek and Roman civilizations (see Chapter I) who improved the systems. One could call this a semi-sustainable linear system with rain water reclamation and reuse. Water was stored in underground cisterns and flowed by gravity to the users. The achievements in water collection, transport, distribution, public health aspects (flushing toilets, public baths) of these ancient civilizations were so advanced that they can only be compared to the water management systems in the developed countries at the end of the nineteenth century. Hence, the future builds on the past and, as will be shown throughout this book, many “new” and proposed technologies of the future such as rainwater and stormwater recycling are technologies of the distant past that were forgotten.

The fast-conveyance drainage infrastructure conceived by Minoans and Romans and reintroduced into the growing cities of Europe during the industrial revolution and into the U.S. cities in the second half of the nineteen century has produced great gains in protecting public health and safety—by “eliminating” unwanted, highly-polluted runoff and sewage. However, the acceptance of fast drainage conveyance systems caused disruption of urban hydrology and polluted most surface waters. Many urban surface waters such as lakes and wetlands were drained or filled for urban uses. In the middle of the twentieth century, surface water quality in cities became unbearable, magnified by introduction of industrial chemicals and fertilizers into the environment. The pollution and disappearance of urban water bodies eliminated all possibilities of on-site reuse but uncontrolled reuse of untreated and later partially treated wastewater continued in cities located downstream. Deteriorating water quality, diminishing flows and population increase led most cities to rely on long transfers of water and regional linear wastewater disposal without reuse. Even after passing groundbreaking water pollution control regulations in the developed countries such as the Clean Water Act in the U.S. and the Water Framework Directive in the European Community countries at the end of the last millennium and billions spent on costly “hard” solutions like sewers and treatment plants, water supplies and water quality remain a major concern in most urbanized areas worldwide. A large portion of the pollution is caused by the predominant elements of the built urban landscape: a preference for impervious over porous surfaces; fast “hard” conveyance infrastructure rather than “softer” approaches like ponds and vegetation; and rigid stream channelization instead of natural stream courses, buffers and floodplains. Because the hard conveyance and treatment infrastructure were designed to provide protection for a five to ten year storm, these systems are often unable to safely deal with the extreme events and sometimes fail with serious or catastrophic consequences.

In the second half of the last century, the world witnessed a rapid emergence and growth of megacities. According to the United Nations, in 1950 there were eight cities in the world that had population of more than 5 million and the terms “megapolis” or “megalopolis” were added to the dictionary. In 2000 the number of megalopoli increased to thirty three and soon (in 2015) we may count close to fifty megalopoli, most of them in the developing world. And this trend will continue. Many of the large urban areas in developing countries lack adequate infrastructure for providing clean potable water and safe disposal of waste. Water and food safety and shortages are major problems which, if the current trends continue, will magnify in the future. China alone will build urban habitats for 300 million people in the next twenty five to thirty years! The Twenty-first century will see the most extensive building and rebuilding of urban settlements driven by population increase and in-migration from rural areas to the cities. At the same time, in developed countries, the water infrastructure, mostly underground, is crumbling, leaking, and being overloaded by undesirable inflows of polluted and “clean” water. Cities are running out of landfill space for solid waste and disposal sites for sludge from treatment plants. At the beginning of this century, in Naples (Italy) garbage and solid waste stayed on the streets for months because no landfills were suitable for the disposal! People in large cities in the developing world have to rely on bottled or boiled water because of insufficient and contaminated water supply.

Awareness of the effects of the excessive atmospheric emissions of green house gases (GHG) (carbon dioxide, methane, nitric oxides, and other gases) on global climatic changes has became a major concern. The consequences of the expected global climatic changes have been scientifically proven. The global community must both reduce GHG emissions and adapt to the changes that cannot be avoided. The expected global climatic changes include increased global warming that will cause more extreme weather, terrestrial glacier and polar ice melting, and melting of permafrost in arctic (tundra) forests. Melting of terrestrial glaciers will increase sea levels and impact coastal communities. Providing water, electric energy, and fuel for transportation and heating has a major impact on global climatic change. The water-energy nexus and its impact on water availability and global climatic change is considered as a major footprint of urbanization along with water and food security, hydrological and ecological effects, nutrient (phosphate) management and future availability for growing crops safely and without severe impacts on water quality. Excessive nutrient losses into receiving waters cause eutrophication and hypertrophy exemplified by massive algal bloom rendering surface water supplies unusable. The microorganisms forming the massive algal blooms prefer warmer temperatures; hence, the emergence of algal blooms may increase with global warming.

Today, the demands of rapid urbanization and depleted or degraded resources drive us to look for totally new systems where used water is recycled, rainwater is harvested, peak stormwater flows slowed down, and discharges of pollutants to remote receiving waters from both pipes and land use are significantly reduced or eliminated entirely. These objectives alter the fundamental functions of the system. This system is intertwined with built environment, transporation, urban landscape, ecology, and living.

Broadly stated, the natural and built environment within urban watersheds is being reconfigured to restore hydrological and ecological functions, provide for the water needs of the community, and maintain the health of people and habitat—with less reliance on energy-intensive, ecologically damaging imported supplies or exported surpluses and waste products that use water for carriage. These system-level changes, which entail significantly greater levels of integration, are emerging in various forms throughout the world.

This book documents the wide spectrum of technological advances that will contribute to that new paradigm. It calls for the integration of technological advances with a radically reformed vision of what constitutes a healthy urban environment. It is premised on the notion that a city’s relationship with the natural world is more complex than simply importing needed resources and disposing of its waste, while accomplishing the multiple transformations, both economic and social, that constitute a city’s primary functions.

The concepts of the new paradigm of sustainable water centric ecocities have been emerging for the last fifteen years in environmental research and landscape design laboratories in several countries of Europe (Sweden, Germany, United Kingdom, Netherlands), Asia (Singapore, Abu Dhabi, Saudi Arabia, China, Japan and Korea), Australia, USA (Chicago, Portland, Seattle, Philadelphia, San Francisco) and Canada (British Columbia, Great Lakes). This paradigm is based on the premise that urban waters are both the lifeline of cities and the focus of the sustainable cities movement. The evolution of the new paradigm of urbanization ranges from the microscale “green” buildings, subdivisions or “ecoblock” to macroscale ecocities and ecologically reengineered urban watersheds, incorporating transportation, food production and consumption and neighborhood urban living. Defining an urban ecoregion concept, focusing on the entire sustainable water cycle, starting with the water supply sources and ending with the wastewater and solid waste recycle and reuse, is becoming a necessity since a city and its water and waste management cannot be separated from its potable water sources and cannot have an unsustainable adverse impact on downstream users, and cities.

Under the new paradigm, used water and discarded solids become a resource that can provide energy in a form of electricity, biogas, hydrogen, fertilizer, raw materials for reuse, and heat. Under this new paradigm, the terms “wastewater” or “waste” become misnomers and are replaced with “used water,” “reclaimed water,” and “resource recovery.” This change can be accomplished by a hybrid (partially decentralized) or even fully decentralized water/storm water/used water system leading to on-site water reclamation and reuse, energy and nutrient recovery and other benefits. The future of sustainable urbanization, arguably, is to switch from heavy energy use and large GHG emissions to “carbon neutrality” or “net zero” carbon effects. The integrated systems do not just include water and used water, integration also includes urban and suburban transportation, heating and cooling, ecology, protection and rediscovery of urban surface and ground water systems, leisure, culture and recreation of citizens. The core concepts of integration of urban water, resources, and energy management are: (a) there are no wastes—only resources, and (b) optimization of resource value requires an integration of water and energy in addition to ecological and social resilience. This change will lead to revitalization of older cities and retrofitting them with sustainable energy, frugal water infrastructure and developing ecologically-healthy water systems. Integrated designs should be based upon maximizing economic, ecological and social equity value and also restoring and protecting ecosystem function damaged by past economic development. Public health benefits would also be considerable. Changing the city environment by laying sidewalks connecting residential areas to schools and shopping, building recreational paths along clean streams and impoundments, making surface water suitable for canoeing, kayaking and swimming, and providing plots for community gardens could change urban life styles to more healthy living. When sidewalks are built and roads are made narrower, people start walking. In one community in Minnesota which implemented such changes people increased their life expectancy by several years (Newsweek, February 15, 2010).

At one level this book attempts to pull together and document all of the component parts and approaches that can contribute to the new paradigm. Ultimately, to be successful however, the authors believe readers must be moved to see the new potential and possibilities that fundamentally different design objectives offer. It is intended for professionals and practitioners in all of the institutions and communities that influence the slow transformation of urban form and function.

Because engineers, scientists, and planners are always constrained by the expectations and requirements imposed by legal, economic, and social institutions, it is important that any new model of urban water management be widely understood and embraced by the citizens, elected officials, local authorities, regulators, developers, businesses, and many others who influence the urban process in every community. When those of us who have a hand on the controls of urban development agree upon and work towards the achievement of new fundamental objectives, it will allow the next generation of practitioners to apply the creative energy, innovation, and integrated solutions needed for a sustainable future. We hope this book contributes to a better understanding of tomorrow’s design objectives, as well as providing insights into the emerging tools available to accomplish them.

These topics are both complex and difficult. They take us out of our professional comfort zone and sit us down with new faces from new communities. But as Thomas Kuhn wrote in his groundbreaking book, The Structure of Scientific Revolutions (The University of Chicago Press, 1996), the change will not be easy. He defined the concept of “paradigm shifts” as

Because it demands large-scale paradigm destruction . . . the emergence of new theories is generally preceded by a period of pronounced professional insecurity . . . Failure of existing rules is the prelude to a search for new ones. (Kuhn 1996, pp. 67-68)

Our mission is to promote and foster that search for new approaches and new rules. If this book contributes to the understanding of what exists, what is being explored, and what can be achieved in the future, the authors will have achieved their objectives.

This book is interdisciplinary, covering the water:energy nexus with its effects on urban development, water supply, drainage, ecology, GHG emissions and system integration. It presents an analysis of the comprehensive problem of unsustainable past urbanization practices and offers hopeful solutions for the sustainable cities of the future. It covers the history of water/stormwater/used water paradigms and driving forces for change (Chapter I) followed by the development of the new (fifth) sustainable ecocity paradigm in Chapter II. Chapters III and IV deal with the old/new urban drainage and best management practices in the context of urban planning and design. The “old/new” term refers to the fact that some drainage concepts call for change from the underground piping infrastructure and impervious urban surfaces, to systems resembling the historic surface drainage and previous hydrology. They are based on switching from fast conveyance drainage employing underground sewers and surface concrete lined channels to storage and infiltration-oriented naturally-looking drainage systems. Chapters V and VI present water conservation, reclamation and reuse systems. In the U.S., the key is to significantly reduce wasting water which in large portions of the country leads to water shortages, and implementing costly and environmentally unsustainable water transfers or high cost desalination. The switch from traditional energy demanding used water and management of residual solids to energy producing and less water demanding new concepts are described in Chapters VII and VIII. Chapter VIII covers energy saving technologies and producing alternate/renewable energy that complement integrated water/resources management. It also presents a proposal for integrated resource recovery facilities converting used water and solids into reclaimed water, biogas, hydrogen, heat and electric energy and recovers nutrients and residual organic solids that can be reused. Stream restoration and daylighting are highlighted in Chapter IX. Clean urban streams and lakes, even small ones, are a dominant part of the urban landscape to which people seem to gravitate, to live on or near, and to use for recreation and enjoyment. They are the backbone of the integrated urban water systems, recipients of clean and highly treated water flows and sources of water for reuse. In the future, clean urban streams could even become a source of energy. Chapter X integrates all the pieces and defines the ecocity, i.e., a water centric sustainable carbon neutral community that balances social, and economical aspects, and at the same time restores or recreates healthy terrestrial and aquatic urban ecology. The ecocity is a place where it is good to live, work and walk around, and to enjoy culture and recreation. Chapter XI presents the goals, unifying concepts and parameters of several built or planned ecocity developments in Sweden, China, United Arab Emirates, and the U.S.

Acknowledgments

This book was conceived as a follow-up of the proceedings of the Wingspread Workshop on the Cities of the Future held in 2006 at “Wingspread” the Frank L. Wright-designed conference center operated by The Johnson Foundation (Cities of the Future, Novotny and Brown, IWA publishing, 2007). This was one of the first instances where the notion of Cities of the Future was discussed extensively by a group of international experts. The discussion continued and COF has now become the major international initiative sponsored by UNESCO and several international professional organizations and associations. At the beginning of this century, several ecocity projects were conceived and some are now being realized. The idea of producing a textbook that could be used in classrooms and as a manual for landscape architects, urban planners, ecologists, civil and environmental engineers and graduate students in these specializations became a logical outcome of this fast spreading worldwide initiative.

A grant provided by CDM (Cambridge, Massachusetts) to the primary author which enabled the bulk of writing and collecting the materials for the book is acknowledged and appreciated. CDM also provided materials and photos of their project sites in the U.S. and Singapore. The authors are also in debt to many contributors to the book who provided materials for the book and permission to use and quote their figures, photos and writing. Dr. Glen Daigger, Senior Vice-president and Chief technology officer of CH2M-Hill Corporation (Denver, Colorado) provided comments, text and graphic materials for the book. Extensive writing and graphic materials were also provided by Patrick Lucey and Cori Baraclough of the Aqua-Tex Scientific Consulting in Victoria (British Columbia) and Herbert Dreiseitl, Principal of Atelier Dreiseitl in Uberlingen (Germany). Numerous other companies and agencies such as Siemens, Arup, Public Utility Board (Singapore), Masdar Development Co. (UAE), Sonoma Mountain Village, City of San Francisco, Sunwize Technologies, GlashusEtt and City of Stockholm (Sweden), Milwaukee Metropolitan Sewerage District and UNESCO’s SWITCH project provided graphic art and information on their ideas, projects and products.

The authors also greatly appreciate the international cooperation with many colleagues interested and involved in COF research and implementation who are now working together in the International COF Steering Committee established and appointed by the leadership of the International Water Association (Paul Reiter, Executive Director and Dr. Glen Daigger, IWA President). The committee leaders are Paul Brown (CDM) and Professor Kala Vairavamoorthy (University of Birmingham, UK) who also directs the UNESCO sponsored SWITCH project on the Cities of the Future.

I

HISTORIC PARADIGMS OF URBAN WATER/STORMWATER/ WASTEWATER MANAGEMENT AND DRIVERS FOR CHANGE

I.1 INTRODUCTION

Since the onset of urbanization millennia ago, cities were connected to water resources, which were their lifeline. Without this connection to water, there would be no cities and, ultimately, no life. When water became scarce, cities were abandoned, and sometimes entire civilizations vanished, as exemplified by the history of the indigenous Hohokam and Anasazi peoples living in the southwestern U.S. in the 15th century, in communities of more than a thousand people—communities that lasted for about a thousand years, but were abandoned, most likely because of extensive drought and the failure of their irrigation systems. Obviously, there were several reasons other than water scarcity causing ancient cities to become ghost towns, then ruins, and finally archeological excavations, centuries or millennia later. Some were related to loss of soil fertility caused by a lack of water for irrigation or poor irrigation practices, which resulted in famine; epidemics of water-borne diseases; exhaustion of the natural resource that was being extracted; or contaminated water, for example, by lead in ancient Rome. Water scarcity is sometimes a result of poor city management and institutions that were inadequate to deal with the multiplicity of conflicting uses and demands for water. Urban waters provided navigation, fish and other seafood, power to mills, laundry, recreation for kings and other nobility, defense during siege by invading armies, and religious significance in some countries and cultures (e.g., India) where certain bodies of water are worshiped.

Water also cleans cities; in historic cities, rainfall washed away the deposits on the streets containing garbage, manure from animals, and human fecal matter. Rainfall and ensuing runoff were—and still are, in many urban areas in some countries—the main and often the only means of disposal of accumulated malodorous solids. During antiquity and the Middle Ages, rivers in sparsely settled rural areas were clean and abundant with fish. In contrast, the environment of ancient, medieval, and post-Industrial Revolution cities was generally filthy and polluted. Terrible epidemics plagued medieval cities, exacerbated by wars and famine. In one medieval epidemic, during a prolonged continental war in the 17th century, 25% of the entire European population vanished.

The situation of urban water resources during the 19th century and in the first half of the 20th century worsened. As cities became industrialized, pollution from industries and loads from reinvented flushing toilets in households (communal flushing toilets were known and used by ancient civilizations of Greece and Rome millennia ago) discharged without treatment into streams resulted in bodies of water devoid of oxygen and smelly due to hydrogen sulfide emanating from decomposing anoxic sediments and water. The response of city engineers and planners was to put the streams out of sight—that is, cover them and/or turn them into combined sewers. In general, until the 20th century, the water environment was not a major interest of architects, builders, or rulers/governments of cities. The people living in the ancient and medieval cities were obviously afraid of epidemics, but the connection between polluted water and diseases was not made until the second half of the 19th century.

The impairments in many urban rivers are caused by the typical characteristics of the urban landscape: a preference for impervious over porous surfaces; fast “hard” conveyance drainage infrastructure, rather than “softer” approaches such as ponds and vegetation; and rigid stream channelization instead of natural stream courses with buffers and floodplains. Under the current paradigm of urbanization, the hard conveyance and treatment infrastructure was designed to provide protection from storms occurring on average once in five to ten years; hence, these systems are usually unable to safely deal with extreme events and prevent flooding, and they sometimes fail with serious consequences. In addition, in many urban river systems, excessive volumes of water are being withdrawn and often transferred long distances, creating bodies of water with insufficient or no flow in some locations, and bodies of water overloaded with effluent and/or irrigation return flows in other areas.

In the mid-2000s, tsunamis and hurricanes struck coastal urban areas, creating catastrophes of enormous proportions. Although these events have occurred throughout history, the human and economic costs of these events were unprecedented. It became painfully evident that the current typical urban landscape and its drainage infrastructure could not cope with these hydrologic events, and the consequences were thousands of lives lost, the suffering and dislocation of survivors during and after these events, and hundreds of billions of dollars in damages. Given that coastal cities are among the fastest growing areas in the world, it is essential to address these problems. Under the circumstance of extreme flows, the current underground urban drainage is almost inconsequential (Figure 1.1), and the hydrologic connection with the landscape is fragmented or nonexistent, providing little buffering protection. Scientific predictions indicate that the frequency and force of extreme hydrologic events will increase with global warming (SPM, 2007; Emanuel, 2005; IPCC, 2007).

On the other side of the hydrological spectrum, many cities, not only in arid zones, are running out of water for satisfying the needs of people. The balanced biota has disappeared from urban bodies of water because of insufficient flow and has either been replaced by massive growths of pollution tolerant undesirable species (sludge worms, massive blooms of cyanobacteria, and other algal species) or disappeared completely. In the 20th century some cities withdrew so much water that rivers downstream from the withdrawal dried up. The traditional response by urban planners and water engineers was to tap water resources from increasingly larger distances. Bringing water from large distances is not a new concept; Romans built aqueducts up to 50 kilometers long, and the Byzantine Empire brought water to its capital city of one million people from up to 400 km (250 mi) away.

Figure 1.1 Impact of Hurricane Katrina in New Orleans (Louisiana) in 2005. Urban infrastructure and human response failed.

Much progress had been accomplished by the end of the 20th century in the U.S. and other developed countries, but despite the progress made in the U.S., many of the nation’s urban water bodies still do not meet the chemical, physical, and biological goals established by the U.S. Congress in the early 1970s. Current research indicates that progress is not only unsatisfactory, but that it may, in fact, have stalled. The fast-conveyance drainage infrastructure conceived of in Roman times to eliminate unwanted, highly polluted runoff and sewage has produced great gains in protecting public health; however, in spite of billions spent on costly “hard” solutions such as sewers, treatment plants, pumping, and long-distance transfers, the safety of water supplies and water quality for aquatic life and human recreation still remain major concerns in most urbanized areas.

At the end of the 20th century, calls for achieving sustainability or green development grew strong and became a mantra for individuals, nongovernmental organizations, and some politicians. Terms for and opinions on “green development and technology,” “smart growth,” “low- or no-impact development,” “LEED- or ISO-CERTIFIED development,” “sustainable development,” and “sustainability” appeared in large numbers in the scientific literature, media articles, and feature shows, sometimes linked to “global warming” and “greenhouse emissions.” Urban planners have also been promoting green- and brownfield developments. There are at least one hundred definitions of sustainability in the literature (Dilworth, 2008). Most of them have certain common intra- and intergenerational denominators—that is, human beings have the responsibility not to damage and/or overuse resources, so future generations will have the same or better level of resources, and one group’s or nation’s use of the resources cannot deprive others from the same rights of use (see Chapter II). Hence, sustainability means balancing economic, social, and environmental needs in an intragenerational context. Because the resources are not unlimited and some are nonrenewable, at the present pace of overuse some could be exhausted in less than one hundred years. It appears impossible, with the available and limited resources, that the rate of consumption and (over)use of resources by some, but not all, people living in developed countries could be extended to the entire and growing population of the world. Therefore, changes are coming, and the goal is to achieve a new, more equitable balance. The rate of water consumption and the magnitude of pollution are directly linked to the use of resources. On the other hand, new and better water and environmental management, reuse of resources and byproducts of urban life, and maintenance or restoration of natural resources will have many beneficial impacts on the health, living environment, economy, and social well-being of people that will extend far beyond the boundary of the cities. It has also been realized that not only natural resources and water are involved; a major component of sustainability is energy consumption and related greenhouse gas emissions causing global warming.

Cities have a significant relevance for sustainable development. McGranahan and Satterthwaite (2003) listed three major reasons why cities are playing a major role: (1) Today more than half of the world population is living in cities, and the proportion of the urban population will be increasing in the future. Cities also concentrate the largest amount of poor people. (2) Urban centers concentrate most of the world’s economic activities such as commerce and industrial production, and, as a result concentrate most of the demand for natural resources and generate most waste and pollution. (3) Cities have the largest concentration of the middle class and wealthy people who work, but do not necessarily live, there; hence, a lot of energy is required for commercial activities and for people living in or commuting to the cities. Cities also impose a large demand on the power generated in fossil fuel power plants, the water brought from large distances, and the food produced in distant, often foreign, farms. Cities also require energy for moving wastes to treatment and disposal sites. All of these activities not only require energy but also emit large quantities of greenhouse gases (GHG).

At the end of the 20th century, and even more so in this century, it has become evident that the urban water infrastructure cannot cope with increasing stresses—and that, in the new millennium, this infrastructure could crumble because of its age and the inherent deficiencies of traditional designs. Now there is widespread movement towards a new interdisciplinary understanding of how the water infrastructure and natural systems must work in harmony to provide fundamental needs, and this movement is ready for success. Urban sustainability concepts and efforts at the beginning of the new millennium were still fragmented, and the role of water resources and water management was perceived differently by landscape architects, urban planners, developers, urban ecologists, and civil and water resources engineering communities. For landscape architects and developers, urban water resources provided attractions for development. For urban ecologists, development was a cause of environmental degradation. For urban planners, surface water resources often represented an obstacle to development and transportation; covering urban streams and bringing them underground used to provide additional space for development, urban roadways, and parking. The civil and environmental engineering community was caught in between. Consequently, the term “watercentric urbanism” had different meanings for these communities. For some urban planners and architects, urban waters often are associated with visual attraction or, in extreme cases, spaces that can be covered and used for more development. This concept could be called “water-attracted development” that can range from clearly unsustainable and vulnerable beachfront developments to city developments, providing visual enjoyment of water and an access to secondary recreation. In this book, “water centric” urbanism means that urban waters are the lifeline of cities, that they must be managed, kept, and/or restored with ecological and hydrological sustainability as the main goal to be achieved. Obviously, such waters would be attractive for a sustainable green development, including protection of riparian zones.

I.2 HISTORIC PARADIGMS: FROM ANCIENT CITIES TO THE 20TH CENTURY

The word “paradigm” is derived from the Greek word paradeigma (πά́ρά́δειγµά́), which means an example or comparison. A paradigm is a model that governs how ideas are linked together to form a conceptual framework, in this case a framework by which people build and manage cities and water resources. A paradigm is first based on logic, common sense, and generational experience, and later on scientific knowledge. It is derived by a discourse in the political domain; science alone may not be the primary determinant of a paradigm. A wrong or outdated paradigm may persist because of tradition, lack of information about the pros and cons of the outdated paradigm, or lack of resources to change it. At the same time, our conceptual models of these systems and our understanding of how they should function and relate to one another have been improving. There are at least four recognizable historical models or paradigms that reflect the evolution and development of urban water resources management; these are outlined in Table 1.1.

Table 1.1Historic paradigms of urban water/stormwater/wastewater management

I.2.1 First Paradigm

This paradigm of water management of ancient cities was characterized by the utilization of local wells for water supply and exploitation of easily accessible surface water bodies for transportation, washing, and irrigation; streets were used for conveyance of people, waste products, and precipitation. The ancient Mediterranean civilizations of Greece and their cities were built on sound engineering principles that incorporated sophisticated water supply systems and drainage. Athens in 500 B.C. had public and private wells and surface drainage (Figure 1.2). Several hundred years later, Romans conquered Greece and adopted and improved their water/stormwater systems. However, urban runoff of ancient and medieval cities was not clean: it carried feces from animals and from people.

The archeological excavations in Pompeii and Herculaneum in Italy (two Roman cities covered by ash during the Vesuvius eruption in 79 A.D.) and elsewhere provide a vivid testimony of the water engineering and management that was typical for the late period of the first paradigm. Figure 1.3 shows a major street in Pompeii which indicates that streets were used for collection and conveyance of urban runoff polluted by animal feces, overflows from fountains, and wastewater from the houses. Human fecal waste was not disposed into the street drainage.

Figure 1.2 Drainage systems in ancient Athens (ca. 500 B.C.). This 1 m x 1 m surface drainage channel is located in the agora (gathering place) of the ancient Greek metropolis (Photo V. Novotny).

Figure 1.3 The Via Abbondanza in the Roman city of Pompeii near Naples in Italy. Stepping stones document that the street was used for drainage. The street also had water fountains conveniently located along the street so citizens and merchants did not have to go far for water. Overflow from the fountains washed the streets (Photo V. Novotny).

As cities grew and local wells could not provide enough water, more sophisticated water designs allowed water to be brought from larger distances by underground delivery systems called qanads, constructed in southeast Asia, North Africa, and the Middle East. Typically with qanads, a large well was dug by manual labor at the foothills of nearby mountains providing abundant water, and the well was connected by a gravity flow tunnel with the city, where it provided water to the population and irrigation of crops. Some qanads brought water from distances as far as 40 kilometers, and the wells and tunnel were dug more than 100 meters deep (Cech, 2005). Cech also noted that qanads are still used today in the Middle East and parts of China.

I.2.2 Second Paradigm

As water demand increased and easily accessed local groundwater, rain, and surface supplies became insufficient to support life and commerce, the second paradigm emerged in growing ancient and medieval cities: the engineered capture, conveyance, and storage of water. This period is characterized by more advanced engineered water systems that brought water from large distances to the cities. As the economies of the states and cities—driven by slave labor—were increasing, water resources became more important for commercial and military navigation, and canals were built around the cities to enhance defense. The beginning of the Middle Ages is usually associated with the conquest of the western Roman Empire by barbarians and the subsequent abolishment of slavery in most European countries. The eastern part of the Roman Empire became the Byzantine Empire and continued for another 900 years.

Figure 1.4 One of the largest Roman aqueducts, Pont du Gard in southern France (former Roman province of Gallia), which is today a UNESCO heritage site (Photo V. Novotny).

Over the centuries the Romans developed extensive systems for water distribution which relied both on wells and on elaborate systems of providing clean water brought from nearby mountains. The first Roman aqueduct was constructed in 312 B.C. (Cech, 2005). The aqueducts of ancient Rome brought water from mountains as far away as 50 kilometers (Figure 1.4). Water was stored in tanks and underground cisterns and distributed by lead or baked clay pipes to fountains, public baths, public buildings, and the villas of the aristocracy. Fountains were located evenly all over the towns so that each homeowner who did not have a private water supply could reach the fountains without any difficulty. Water supply pipes were laid along the streets, providing water continuously to fountains, each with an overflow directed onto the street surface. As shown on Figure 1.3, the street also provided drainage of stormwater (Nappo, 1998). Figure 1.5 shows an example of a house in Pompeii built with a courtyard (atrium) in the middle, where the rain-collecting cistern was located and all roof runoff was directed. The practice of rain harvesting and storing rainwater in cisterns was also typical in many ancient and medieval cities and is still common in many communities in dry Mediterranean regions and elsewhere.

Romans were not much concerned with the disposal of wastewater, as long as it did not pose a great nuisance. Paved streets in most cases were continuously washed by the overflow from the fountains and by rainwater. In Roman cities common people washed themselves in public baths, which were also a place for socializing. In Pompeii and other cities, laundry was done in commercial laundries and cleaning shops. Some cities also had communal flushing toilets. To handle pollution of urban runoff and the flow of wastewater from baths and public buildings, sewers were invented. This invention allowed polluted street flows and wastewater to be conveyed underground to the nearest rivers. The Roman sewer, the Cloaca Maxima, has been functioning for more than two thousand years (Figure 1.6); however, sewers were installed a thousand years later in other European cities.

Figure 1.5 Atrium of a large house in Pompeii. Roof rainwater was directed into the basin in the center, from which it was directed into an underground cistern. Overflow was conveyed to the street (Photo V. Novotny).

In contrast, in medieval cities of Europe (with the exception of Muslim regions of Spain and the Balkans), common people and even the nobility had poor personal hygiene, rarely took baths, and had no showers. As a result, domestic per capita water use in medieval European cities was much smaller than in Roman cities or modern cities, most likely at the level that today would be considered a minimum daily use. Most excreta and fecal matter were disposed on site in outhouses and latrines. Like those of ancient cities, street surfaces were polluted by fecal matter and trash. Solid waste deposits on streets of medieval Paris were sometimes 1 meter high, and night chamber pots were generally emptied into street drainage.

Figure 1.6 Outlet of the Roman sewer, the Cloaca Maxima (Largest Sewer) into the Tiber River. The sewer is functioning today, but a barrier was installed to prevent entry because of security concerns.

Ancient Rome and medieval Constantinople had populations of about one million at their height, while medieval London, Paris, Amsterdam, and Prague had populations in tens of thousands, at most, and Berlin was a village. Constantinople (present-day Istanbul in Turkey) on the shores of the Bosporus was the capital of the Byzantine Empire, which lasted until the 15th century A.D., and for more than a thousand years it was the center of East European and Mediterranean civilization. After the conquest of Rome by barbarians in the 5th century, it was the cultural and commercial center of the world. This city inherited—and improved upon—Roman culture and engineering know-how when the Roman Empire split into its eastern and western parts. Its water system was similar to that of Rome, using aqueducts to provide fresh water, but also relying heavily on private and public rainwater harvesting and cisterns. The longest aqueduct (400 km) was built in the 4th and 5th centuries to provide water to this megalopolis. Water was stored in more than one hundred cisterns throughout the city that provided 800,000 to 900,000 m3 (211 to 238 mg) of storage. In the 7th century the city built its largest underground cistern (Figure 1.7).

Figure 1.7 This underground Basilica cistern, capable of storing 80,000 m3 (21.1 mg) of water, was built at the beginning of the seventh century in Constantinople, the capital of the Byzantine Empire (present-day Istanbul in Turkey) (photo V. Novotny).

Another large medieval city with more than 200,000 inhabitants was Venice (in present-day Italy), which was a center of the powerful Venetian Republic (697-1795 A.D.), competing with the Byzantine Empire over the dominance of the Mediterranean region. The city is located on 118 small islands inside the 500-km2 Lagoon of Venice and is known for its famous canals. Historically, Venice relied on private and public wells and fountains, and all sewage was discharged directly into the canals. Essentially, the Republic of Venice, including its other cities (Padua, Verona), operated its water and wastewater disposal using the concepts of the first paradigm, although it periodically dredged the canals within the city to remove accumulated sludge. The city also built a network of canals on the mainland surrounding the lagoon and relocated two major rivers outside of the lagoon to prevent its siltation. The historic city of Venice, which today has about 80,000 permanent residents and many thousands of tourists, still discharged all wastewater into its canals with minimum treatment at the end of the last millennium. Since the beginning of the 21st century, low-level distributed treatment has been implemented in the historic city.

A pipeline system delivering water to London from the Thames River and nearby springs was built at the beginning of the 13th century, and by the end of 18th century, major European cities had a water distribution system that relied on public fountains and deliveries of water by pipelines to individual houses. Many public fountains in medieval cities were pieces of art (Figure 1.8). For most of the medieval era, water supply pipelines were made of baked clay or wood (Figure 1.9), and were replaced by cast iron later in the 19th century. Large sewers were of masonry. In some cities water to individual houses was provided by private water vendors (Cech, 2005). Most houses, however, had only one faucet with a sink. Sewers were not common, and many smaller and even middle-sized cities in Europe did not have sewers until the 20th century. The use of standpipes and/or private vendors for water distribution can still be found in many undeveloped countries. The end of the second paradigm could be dated to the middle of the 19th century, when the servitude of rural people to their feudal masters in Europe and slavery in the U.S. were broken, which resulted in a massive population migration into cities. This was the beginning of the Industrial Revolution, which shifted the economic power to the cities, away from the landholding nobility who had held the rural population in servitude (or slavery).

Figure 1.8 Caesar Fountain in Olomouc in the Czech Republic, sculpted and built in 1725 (Photo V. Novotny).

Figure 1.9 Making wood pipes for the medieval water supply systems (courtesy: Museum of Water Supply in Prague, Czech Republic).

I.2.3 Third Paradigm

Beginning in the first half of the 19th century, the freed rural population migrated to cities and joined the labor force in rapidly expanding industries, then run more by steam and fossil fuel (dirty) energy than the clean water or air energy (water wheels or wind mills) typical for small industries and mills during the second paradigm. This change, along with the ensuing rapid expansion of cities, increased urban pollution dramatically. In the second half of the 19th century, sewers were accepting domestic and sometimes industrial black sewage loads. However, most industries clustered near the rivers discharged effluents directly into streams without treatment. Because urban water bodies served both for water supply and wastewater disposal, sewage cross-connection and contamination of wells and potable water sources caused widespread epidemics of waterborne diseases.

The third paradigm of urban water and wastewater management added a massive investment in building sewers, in trying to cope with the pollution of urban surface waters. Urban water bodies were becoming unbearably polluted and a serious threat to public health. Other monumental projects included flood controls by stream straightening, lining, and ultimately covering; building thousands of reservoirs for water supply and hydropower; navigation river projectsand canals. Even today, $30-$40 billion (in 2000 dollar value) are spent annually on new dams worldwide (Gleick, 2003), and monumental cross-country canals and water transfers are being built or planned, such as a canal bringing water from the water-rich Yangtze River to Beijing and other cities located in the water-poor Northeast of China. A transcountry canal is planned in the Republic of Korea.

Since the end of the nineteenth century communities were building combined sewers and treatment plants for potable water, as engineering methods to solve the problem of pollution of surface waters. Flushing toilets changed the way domestic fecal matter was disposed. Until then collection tanks and pits in outhouses and latrines were emptied periodically by private haulers. The introduction of flushing toilets and bathrooms conveyed fecal and other wastewater into the newly built or existing stormwater sewers. The goal of pollution control was fast conveyance of wastewater and urban runoff out of sight from the premises to the nearest body of water.

Wastewater treatment, at the end of the 19th century and beginning of the 20th century, was limited to sedimentation and self-purification in the receiving water bodies. This was not even remotely sufficient to resolve the nuisance problem with sewage discharges. One solution was to pump sewage and apply it onto fields for crop irrigation, which was practiced in the late 1800s around London, Berlin, Paris, and Sydney (Cech, 2005), Mexico City (Scott, Zarazua, and Levine, 2000), in China, and in many other locales. In the late 1800s, septic tanks and leaching fields were first used in the United States, and these are still used today in places without sewerage. In Europe in the early 1900s, sedimentation of solids in sewage and anaerobic digestion of the deposited solids were done in septic tanks (Figure 1.10) known as Imhoff tanks (commemorating German pioneer of sanitary engineering Karl Imhoff). Activated sludge plants, trickling filters, and sewage lagoons were invented in the early 1900s.

Figure 1.10 The Imhoff tank combined primary settling with anaerobic digestion of settled sludge. It was invented by Karl Imhoff in Germany at the beginning of the 20th century. The tank has an aerobic settling compartment in the middle, anaerobic sludge digestion in the lower part, and scum-collecting volume on the top (Replotted from Novotny et al., 1989).

Figure 1.11 Converting Mill Creek into a sewer in Philadelphia (PA) in 1883 (photo provided by the Philadelphia Water Department Historical Collection).

At the same time, covering streets and other areas of cities with impervious pavements was preventing rainfall infiltration and, concurrently with the increased withdrawals of water from streams, depriving urban streams of the base flow needed for dilution of pollutant loads between the rains. During dry weather, some streams carried mostly sewage and became effluent dominated (see Chapter IX). The solution was to put small and medium-sized urban streams out of sight and convert them to combined sewers (Figure 1.11). The aim of these fast conveyance urban drainage systems (sewers, lined and buried streams) was to remove large volumes of polluted water as quickly as possible, protecting both public safety and property, and discharging these flows without treatment into the nearest receiving body of water. Almost all sewers, even the old ones originally designed to carry heavily polluted urban runoff from streets, were combined—that is, they carried a mixture of sewage, infiltrated groundwater, and stormwater flows. Over a relatively short period of fifty to one hundred years, most of the urban streams disappeared from the surface, as shown on Figure 1.12.

In the absence of effective treatment technologies that would remove putrescible pollution from sewer outfalls and heavily polluted urban runoff (most of the street traffic was still by horse-drawn wagons and coaches), city engineers resorted to grandiose projects to alleviate the pollution problems. In Boston, Massachusetts, several square kilometers of the tidal marsh of the Charles River estuary called the Back Bay, plagued by standing sewage pools, were filled between 1857 and 1890 and converted to upscale urban development that more than doubled the size of the city at that time. Approximately at the same time, a large tributary of the Charles River named Stony Brook was causing a nuisance and threatening public health. Because of public health regulation for sewer discharge points, lowlands in the neighborhoods into which the brook was discharging became terminal sewage pools. Periodic epidemics swept through the city regularly. Raw sewage from Stony Brook flowed directly into the tidal Back Bay, with environmentally destructive results. Historian Cynthia Zaitzevsky (1982) describes the effect of sewage on the Back Bay: “...the residue lay on the mud flats, baking odiferously in the sun. Eventually it became incorporated into the mud. Under these conditions, the last vestiges of the salt marsh could not remain healthy for long. When the park commissioned a survey of the area in 1877, animal life was no longer able to survive in the waters of the Back Bay.” As a result, a 12-kilometer stretch of the brook through the city was buried and converted into large box culverts. Only names such as Stony Brook Park or Stony Brook subway and train station remain, and most of the Boston population does not even know that a medium-sized historic river existed in the city 150 years ago. Figure 1.13 shows the old gate house where Stony Brook went underground. After sewer separation in 2002, the relatively clean water originating in a headwater nature conservancy area upstream is now flowing in a double culvert storm sewer, while a large portion of a once very lively and important part of the city that used to surround the brook has deteriorated. The gate house shown in the figure is gone today, but the river is still underground. The practice of burying small and medium streams and converting them into subsurface sewers was common to almost every city in the world, ranging from small to large.

Figure 1.12 Disappearance of streams in the Tokyo (Japan) Metropolitan area (Courtesy Prof. Horoaki Furumai, 2007).

Because of the poor sanitation and discharges of untreated wastewater into groundwater and surface water bodies, terrible epidemics of waterborne diseases plagued the urban population throughout the Middle Ages until the end of the 19th century. The cholera epidemics in Chicago (Illinois) in the late 1800s, caused by contamination of the city’s water intake from Lake Michigan, led the city government to commission the building of an engineering marvel, the Chicago Sanitary and Ship Canal (CSSC), finished in 1910. The canal reversed the flow of the Chicago River, which had originally flowed into Lake Michigan, diverting it into the Des Plaines River (Figure 1.14) that flows, after becoming the Illinois River, into the Mississippi River (Macaitis et al., 1977; Novotny et al., 2007). In this canal and the Des Plaines River, all sewage and most of the overflows from the combined sewers (CSOs) are diverted into the Illinois River, a tributary of the Mississippi River, and do not contaminate the water intakes in Lake Michigan. The CSSC is now one of the largest inland shipping waterways, larger than the Suez Canal, and the Lower Des Plaines River is also the largest effluent dominated body of water in the world (see Chapter IX).

Figure 1.13 The gate house with bar racks through which Stony Brook in Boston (Massachusetts) entered underground into 12-km- long culverts more than one hundred years ago.

Source: Charles Swift, BostonHistory.TypePad.com)

The third paradigm period had numerous other pollution catastrophes due to unregulated or poorly regulated point source discharges and absolutely no controls of diffuse (nonpoint) pollution. Severe cases of painful and deadly mercury and cadmium poisoning of fishermen in Japan were reported in the 1960s. Minamata mercury poisoning disease was first discovered in Japan in 1956, and another outbreak occurred in 1965. As a result of fish contamination, thousands died and tens of thousands were infected. As a result of point pollution, many streams were dead, smelly water bodies with sludge deposits that could only harbor dense populations of sludge worms (Krenkel and Novotny, 1980).

By the end of the 19th century, people began to understand that unsanitary living conditions and water contamination contributed to disease epidemics. This new awareness prompted major cities to take measures to control waste and garbage. In the United States, industrial chemicals and wastes, including sulfuric acid, soda ash, muriatic acid, limes, dyes, wood pulp, and animal byproducts from industrial mills, contaminated waters. In the industrial U.S. Northeast and Midwest, and also in industrial Europe, almost all major and middle-sized rivers were severely affected by pollution. New pollutants such as household detergents formed foam on the weirs 5 meters or more thick. The Cuyahoga River in Cleveland, Ohio, which flows into Lake Erie, became so polluted that the river caught on fire (Figure 1.15) several times between 1936 and 1969. The fire was due to floating debris and a thick layer of oils floating on the surface of the river.

Figure 1.14 The effluent dominated Des Plaines River in Joliet, Illinois, after the confluence with the Chicago Sanitary and Ship Canal. It has become one of the largest inland waterways in the U.S. Photo V. Novotny.

In the mid-1850s, Chicago built the first major primary treatment plant to treat its sewage in the United States. From 1880 until well into the second half of the 20th century, water pollution control efforts in the U.S. and industrialized countries of Europe focused on removal of objectionable solids, disease-causing pathogens, and oxygen-demanding organic substances (BOD) that were turning receiving water bodies into unsightly, oxygen-deprived black-colored smelly streams or pools. During the third paradigm period, primary and later secondary wastewater treatment technologies were introduced in several cities but did not address the overall, uncontrolled water-sewage-water cycle (Imhoff, 1931; Lanyon, 2007; Novotny, 2007) in which water in an upstream community is converted to sewage, discharged into a receiving water body, and reused downstream as potable water by another community (see Chapter IX). Dissolved oxygen concentrations preventing fish kills provided guidance for estimating the waste-assimilative capacity of streams. The primary reason for installation of treatment plants by some communities was protection of public health and avoidance of nuisance from unsightly and odorous anoxic urban waters.

Figure 1.15 The fire of the Cuyahoga River in Cleveland, Ohio, in 1952. Source: Cleveland Press Collection, Cleveland State University Library.

Increasing imperviousness. Paving the cities and roads dates back to ancient Greece and Rome (see Figures 1.2 and 1.3