Providing Safe Drinking Water in Small Systems

Technology, Operations, and Economics

Joseph Cotruvo, Gunther F. Craun, Nancy Hearne, Joseph Cotruvo, Gunther F. Craun, Nancy Hearne

• Publisher: Routledge
• Year: 2019
• eBook ISBN: 9781351420976
• Topic: Technology & Engineering
• Subtopic: Environmental Management
• Index: Technology & Engineering

The continued lack of access to adequate amounts of safe drinking water is one of the primary causes of infant morbidity and mortality worldwide and a serious situation which governments, international agencies and private organizations are striving to alleviate. Barriers to providing safe drinking water for rural areas and small communities that must be overcome include the financing and stability of small systems, their operation, and appropriate, cost-effective technologies to treat and deliver water to consumers. While we know how to technically produce safe drinking water, we are not always able to achieve sustainable safe water supplies for small systems in developed and developing countries. Everyone wants to move rapidly to reach the goal of universal safe drinking water, because safe water is the most fundamental essential element for personal and social health and welfare. Without safe water and a safe environment, sustained personal economic and cultural development is impossible. Often small rural systems are the last in the opportunity line. Safe Drinking Water in Small Systems describes feasible technologies, operating procedures, management, and financing opportunities to alleviate problems faced by small water systems in both developed and developing countries. In addition to widely used traditional technologies this reference presents emerging technologies and non-traditional approaches to water treatment, management, sources of energy, and the delivery of safe water.

Chapter 1
Worldwide Drinking Water: Problems and Prospects

Poto ergo sum.

I drink (water), therefore I am.

Yo tomo agua, por lo tanto, yo existo.

Je bois donc je suis.

After Descartes

Lack of access to safe drinking water is a major cause of ill health and, therefore, an injustice.

Dr. A. David Brandling-Bennett

Deputy Director

Pan American Health Organization

THE WATER CHALLENGE

A. David Brandling-Bennett

I. ECONOMIC IMPORTANCE OF WATER

Water is one of several resources without which a nation cannot satisfy the fundamental needs of its people or achieve its important national goals and economic development. Just like other critical resources, such as air and soil, it must be protected from overuse and misuse in order that nations may prosper and civilization flourish. Deterioration in the quality of surface water and groundwater becomes more likely and more critical as nations become more industrialized and urbanized and as competing demands for water increase. Commonly, little value is placed on water when it is readily available. As the natural supply becomes more fully utilized or even exhausted and competition between users intensifies, the value of water increases. As a consequence, new approaches for regulating and pricing water and related services are needed. The use of water resources plays an important role in overall economic development in all countries. The challenge is to decide what policies a nation should adopt so that this fmite and valuable resource yields maximum benefits to society and is sustainable for future generations. Furthermore, water policies must take into consideration land-use planning and environmental protection. Water conservation should be an integral part of national development policies.

II. WATER SCARCITY

The amount of water available to people is fmite and depends on climatic conditions and hydrological factors. Economic, social, and health problems that result from insufficient water are a primary concern. The proper allocation of water resources for domestic consumption is essential to health, because water scarcity eventually leads to problems of water quality and exposes populations to infectious diseases and pollutants that are associated with insufficient or contaminated water. Below a certain quantity of water, considered to be between 35 and 100 liters per capita per day, countries begin to experience periodic or regular water stress. Scarcity of renewable freshwater is a problem for millions of people around the world. It is currently estimated that more than 430 million people live in countries considered “water-stressed”. The present and future availability of renewable freshwater in populated areas depends on the existing freshwater ecosystem and underground aquifers. By the middle of the next century, the population residing in water-stressed areas will have increased anywhere from three to fivefold. The Region of the Americas is relatively well endowed with water resources in general. However, several nations are approaching water scarcity, especially island countries where the sustainable yield of freshwater cannot be expanded. Water scarcity can also mean deterioration of water quality, which may result from excessive pumping of surface and groundwater with intrusion of salt water or other contaminants.

The implications for water resources management are clear. Countries with limited water resources need to be particularly careful in the management of those resources. Agenda 21, which was adopted at the United Nations Conference on Environment and Development in 1992, recognizes that the fragmentation of responsibilities for water resource development among sector agencies is a great impediment to integrated and holistic management of freshwater as a fmite, vulnerable resource. The integration of sector planning and programming within the framework of national economic and social policy is of paramount importance. Recommendations for action include integrated measures for protecting and conserving sources of freshwater, including an inventory of water resources, and the promotion of water conservation through improved efficiency and minimization of wastage by all users. The slowing of population growth worldwide may reduce somewhat the pressure on freshwater and underground aquifers, but water will undoubtedly become an increasingly valuable and expensive resource in the future.

III. WATER AND HEALTH

The alteration of rivers, lakes, aquifers, and other systems as a consequence of human activities, such as dam construction, irrigation schemes, deforestation, and urbanization, has a considerable impact on water ecology and human health. In addition, domestic and industrial waste and agricultural activities often contaminate water sources. Water is an important vehicle for many serious infectious diseases. Water used for food preparation, beverages, ice, shellfish harvesting, recreation, as well as the irrigation or freshening of food crops, has been responsible for the transmission of numerous infectious agents.

The most common health impact of water contamination is diarrheal disease, which often results from drinking water that has been contaminated through unsafe disposal of sewage. Diarrheal diseases are among the top three causes of death worldwide and the leading cause of death among children under 5 in most developing countries. In the Americas, they account for 20 percent of deaths in this age group. The outbreak of cholera in Latin America, which started in Peru in January 1991 and subsequently spread through South and Central America, was caused in large part by the lack of sanitary infrastructure in the countries, and in particular the absence of effective water treatment and disinfection. It has resulted in more than 1.2 million cases and nearly 12,000 deaths during the last 7 years and has had a major impact on the health infrastructure and economies of affected countries. The rapid spread of cholera in the region shows how quickly inadequate water supplies and basic sanitation can adversely affect health. Today, the continuing presence of endemic cholera in this region serves as a reminder of the inadequacy of basic sanitary infrastructures in our countries.

Taking into consideration the economic importance of water and its health implications, the Santa Cruz de la Sierra Summit, held in Bolivia in 1996, issued a Declaration recommending that all governments promote equitable access to basic health services and safe water supplies. In particular, they should strengthen their programs to improve water quality, increase access to safe water, and fight water pollution. These recommendations were reiterated at the Second Summit of the Americas, which was held in Santiago de Chile in April 1998. In addition, the Environmental Leaders Summit of the G7 countries produced the 1997 Declaration of the Environment Leaders of the Eight on Children’s Health, which focuses attention on the provision of microbiologically safe water to protect children’s health.

IV. WATER COVERAGE IMPROVEMENT

The most recent WHO statistics indicate that, in 1994, 1.1 billion people, or 25% of populations in developing countries, did not have access to safe water. The figure varies considerably between regions. Based on actual surveys, the coverage of water and sanitation in Latin America and the Caribbean has not increased significantly since the beginning of this decade. There is a need not only to provide new facilities but also to sustain existing ones through adequate operational and maintenance systems and ensure their proper utilization through appropriate health and hygiene education. Making water supplies a sustainable reality in the developing world is a major challenge, especially in small water systems which often lack the technical, financial and human resources for proper and efficient operations.

The survey of water supply and sanitation in Latin America and the Caribbean indicates that, by 1995, 73% of the population (excluding the United States and Canada) had regular access to water by house connection or to a water source at a reasonable distance. There are still large gaps between and within countries and in particular between urban and rural areas. The report further recognizes several deficiencies with regard to the quality of services, such as a large percentage of water that is unaccounted for, intermittent supplies, and shortcomings in operation and maintenance that may result in contamination of water supplies. In addition, several constraints continue to plague the sector and need to be addressed by policy makers. These include inadequate organization, difficulty in recovering investments and in generating income through payment for services, wasteful use of water, and the need for human resources development. The recent movement toward modernization and reform by some governments and increased participation of the private sector directly respond to these needs and represent an effort to overcome financial and managerial constraints.

An economically sound system of user charges for water services will conserve water supplies, promote appropriate investment in water development projects, reduce the fmancial burden on those who do not benefit from the services, and allocate water more efficiently among users.

Any substantial development of water resources and improvement in coverage and quality of water will depend on the political commitment of governments to allocate the necessary resources. In this context, the Summits of Santa Cruz de la Sierra and Santiago de Chile provide an excellent political basis for action. The Pan American Health Organization (PAHO), in partnership with bilateral agencies, other organizations of the Inter-American and United Nation systems, and other regional and subregional organizations, is committed to assist governments and communities in their efforts to increase access to safe water and improve the quality of drinking water. To support the implementation of this initiative, these partner organizations propose to establish a Regional Program for the Provision of Bacteriologically Safe Water, aiming at the exchange of information, experiences, and technologies among the countries. The Program will have a strong component of community participation dealing with water conservation, source protection, household storage, and disinfection. The major components of the Program will include the following:

• Policy and legislation. The countries should revise and update their policies, regulations, and legislation to be consistent with the WHO Guidelines for Drinking Water.

• Training and information. Regional efforts for technology dissemination, training, and information systems will be intensified.

• Sanitary education and social mobilization. Governments will promote active participation by the social sector and mount public information and educational campaigns to raise awareness about safe drinking water.

The initiative includes the strengthening of laboratory capacity in the region and will place particular emphasis on improving disinfection in small systems. To improve water quality and achieve sustainable service, it is essential that decision makers and the population they represent be aware of the relevant health issues concerning water and participate fully in the process.

The provision of safe drinking water in developing nations remains a major challenge for planners, water engineers and technicians. PAHO and WHO will continue to support their Member States in that important effort. While there is no general prescription for safe drinking water, some simple rules apply:

• watersheds and water sources need to be protected and properly managed

• ground and surface water must be protected by appropriate legislation

• production facilities must be properly operated and maintained

• water must be treated to standards

• all water should be disinfected

• consumers must be educated and take an interest in their water systems

V. CLOSING

This Organization is proud to associate itself with NSF International, a WHO Collaborating Center, and the other sponsors of the First International Symposium on Technology, Operations and Economics of Providing Safe Drinking Water, held May 10–13, 1998, in Washington, D.C. During this symposium, participants deliberated on important issues, such as disinfection, operation, maintenance and management, all of which are often neglected or absent, especially in small systems. Nevertheless, they are essential for providing safe water to the world’s population. We are grateful for recent advances in disinfection technologies that have proved useful in controlling cholera epidemics in Latin America. We are hopeful that new and emerging technologies will make it easier for small communities to get access to safe water. This Symposium was an important step to bring together health officials and water managers to address these problems.

Lack of access to safe drinking water is a major cause of ill health and, therefore, an injustice. PAHO stands fundamentally...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• About the Editors
• Acknowledgments
• Table of Contents
• Preface and Welcoming Remarks
• Chapter 1 Worldwide Drinking Water: Problems and Prospects
• Chapter 2 Ensuring the Sustainability of Small Systems
• Chapter 3 Water Treatment Technologies: Disinfection of Waterborne Pathogens
• Chapter 4 Water Treatment Technologies: Filtration and other Treatments to Remove Microbial or Chemical Contaminants
• Chapter 5 Pre-Engineered Water Treatment Systems: Point-of-Entry, Point-of-Use, Package Plants, and Bottled Water
• Chapter 6 Analytical Monitoring
• Chapter 7 Well Remediation, Energy Sources, and Delivery of Water: Emerging Technologies and Approaches
• Chapter 8 Systems Solutions: Management, Operation, and Maintenance
• Chapter 9 Small Water System Assistance and Training Programs
• Chapter 10 Regulatory Structures for Small Systems
• Epilogue
• Indexes