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Class A biosolids can be produced using low-cost, low-technology biosolids treatment processes including lagoon storage, air drying, and cake storage. This project reviewed the available literature and municipal agency data about these processes. This report presents design and operating guidelines distilled from the review process. It is designed for wastewater treatment plant (WWTP) managers, operators, and engineers who wish to discern whether these processes, used alone or in combination, might be practically applied at specific plants. This report also describes the U.S. regulatory environment in relation to producing Class A Biosolids and defining Class A processes. It also presents a list of recommended research needs. This report: Familiarizes WWTP managers, operators, and engineers with low-cost, low-technology biosolids treatment processes, likely pathogen kill mechanisms, and practices that have reduced pathogen densities to Class A levels at scales ranging from laboratory tests to large municipal biosolids treatment operations. Presents guidelines for producing Class A biosolids under a variety of conditions. Describes low-technology treatment processes within the Class A regulatory framework, identifies satisfactory end conditions for products created from low-tech treatment processes, and provides guidance in developing national or site-specific certification as processes equivalent to a process to further reduce pathogens (PFRP).

The purpose of this project was to develop a methodology for deriving site-specific nutrient criteria (SSNC) for surface waters, including streams and rivers, lakes and reservoirs, and coastal estuaries. The methodology was developed to extend the United States Environmental Protection Agency?s regional nutrient criteria for localized conditions characterized by particular desired water quality requirements or designated uses. The proposed SSNC methodology provides local stakeholders with a recipe for estimating nutrient criteria consistent with site-specific water quality management goals and objectives. The SSNC methodology prescribes a three-tiered or sequential approach for defining concentrations of acceptable nutrients in relation to management goals and objectives. Each tier requires successively more site-specific data and information and also develops increasingly quantitative and technologically more detailed relationships between nutrients and stated water quality measurements (chlorophyll a, Secchi depth, dissolved oxygen). The SSNC process can be initiated at any tier, although most applications will likely progress from Tier 1. The derivation of Tier 1 SSNC relies extensively on existing data and regional nutrient criteria. Tier 2 adds additional, more site-specific data and estimates SSNC on the basis of statistical relationships between nutrients and the selected water quality parameters of interest. Tier 3 extends Tier 2 through the development of additional site-specific data and the application of site-specific, process-level water quality models to estimate the SSNC. Follow-up monitoring is a key component of all three tiers for assessing the effectiveness of the SSNC in achieving the desired water quality characteristics and making subsequent decisions about continued implementation or modification of the SSNC. Benefits: SSNC can serve as effective alternatives to regional criteria, which may fail to achieve or sustain locally desired water quality conditions. The proposed methodology prescribes an efficient and economical approach for achieving site-specific water quality objectives. The methodology develops SSNC on the basis of process-level understanding of relationships between nutrients and water quality objectives. The tiered approach permits a sequential, increasingly detailed and sophisticated analysis of relations between nutrients and desired water quality conditions. The results of the tiered SSNC methodology provide direct inputs to localized management and decision-making processes.

The articles compiled in the book describe the current situation in China with respect to surface water quality and wastewater treatment, and provide results of specific research projects, leading the way to a China-specific up-to-date water treatment technology.

Recent technical innovations and significant cost reductions have sharply increased the potential for using Membrane Bioreactor (MBR) technology in municipal wastewater treatment. MBR technology displays several advantages compared to the traditional activated sludge processes, such as high effluent quality, limited space requirement and with the possibility of a flexible and phased extension of existing waste water treatment plants. Membrane Bioreactors for Municipal Wastewater Treatment describes the results of a comparative research programme involving four leading membrane suppliers: Kubota (Japan), Mitsubishi (Japan), X-Flow (Netherlands) and Zenon (Canada). Each supplier provided a pilot to represent a suitable scale - right up to full scale. These pilots were operated and optimised in the course of the research programme to achieve the best operating window under different operating regimes. The research focussed on the functionality of the membrane, the biological treatment, membrane fouling, achieved effluent quality, and system operability as well as other factors. In a number of side studies the required pre-treatment, membrane fouling/cleaning, energy usage, effluent quality and sludge processing were also addressed. The comparative pilot research was carried out by DHV Water on location at the wastewater treatment plant at Beverwijk in the Netherlands.

The objective of this project was to develop and evaluate a practical technique to indicate the probability of the presence of bacterial pathogens in receiving waters. A practical method was defined as one that would limit the use of defined culture-based microbiological methods, and would be based on: (1) validating indicator organisms that predicted the presence of pathogens, or (2) detection of pathogens by polymerase chain reaction (PCR)-based assays. The study also assessed the utility of PCR-based technology for bacterial pathogen detection with respect to technology transfer to a wider range of water and wastewater facilities.

Plant-availability of metals in biosolids-treated soils may be mathematically described by Mt = C x [1 - e- (k x t)] where Mt (mg kg-1) is the cumulative metal removal from the biosolids-treated soils by growing and harvesting plants for t years, C is the total phytoavailable metal pool of the soil (mg kg-1) at t = 0, and k is the metal absorption rate coefficient (yr-1). The total available metal pool, C, is defined as metals extractable by organic acids in the rhizosphere of growing plants and k is related to the kinetics of metal release by organic acids. Half-life of the available metals in biosolids-amended soils may be derived from k.Experiments were conducted to characterize the concentration and composition of the organic acids. A successive extraction method was used to extract metals from biosolids-treated soils for determinging C and k. In this manner, the plant available metals of the biosolids-treated soils are defined by the total available metals, half-life, and duration of plant growing.

This is a best practice manual for addressing water losses in water distribution networks worldwide. Systems and methodologies are presented for improving water loss and leakage management in a range of networks, from systems with a well-developed infrastructure to those in developing countries where the network may need to be upgraded. The key feature of the manual is a diagnostic approach to develop a water loss strategy - using the appropriate tools to find the right solutions - which can be applied to any network. The methods of assessing the scale and volume of water loss are outlined, together with the procedures for setting up leakage monitoring and detection systems. As well as real losses (leakage) procedures for addressing apparent losses, by introducing regulatory and customer metering policies are explained. Suggestions are made for demand management and water conservation programmes, to complement the water loss strategy. Recommendations are made for training workshops and operation and maintenance programmes to ensure skills transfer and sustainability. The manual is illustrated throughout with case studies. Losses in Water Distribution Networks will appeal to a wide range of practitioners responsible for designing and managing a water loss strategy. These include consultants, operations managers, engineers, technicians and operational staff. It will also be a valuable reference for senior managers and decision makers, who may require an overview of the principles and procedures for controlling losses. The book will also be suitable as a source document for courses in Water Engineering, Resource Management and Environmental Management.

Water services include water supply, sewerage and stormwater drainage. The facilities needed for these services are pipelines, reservoirs and treatment works; but the service goes beyond the infrastructure. It includes economics, billing, and business management. Although these services exist in every city, being advanced by the growing use of automation and information technology, costs are also increasing without many consumers seeing increased benefits. Customer service is therefore becoming important to the industry. Water Services Management is intended to educate engineers to manage and improve water services, rather than simply designing and constructing treatment works and distribution systems. The text covers water supply and drainage from the hydraulic and economic points of view, and while design and construction practices are reviewed, the focus of the book is on improving existing systems to turn the emerging industry into an attractive business. Topics covered include: Potable water supply, sewerage and stormwater drainage. Hydraulic management: storage, peak flow attenuation and pumping. Water quality: standards, pollution control and treatment. Infrastructure management: rehabilitation, reconstruction, upgrading and maintenance. Economic efficiency: asset management, privatization, and risk analysis. Improving economic viability via efficient use of energy and construction project management. Characteristics encountered in developing countries are also considered, including: Low cost sanitation, water supply standards and off-grid energy sources. Capacity building and appropriate technologies. Financing, operation and benchmarking.

A new development for the treatment of domestic wastewater is a technology based on aerobic granular sludge. This report describes the results of research carried out at the Technical University of Delft.

Sustainable Water Services: A Procedural Guide is the result of the Sustainable Water industry Asset Resource Decisions (SWARD) project, undertaken by a consortium of UK academics in collaboration with water service providers in Scotland, England and Romania. It has been developed to act as a practical tool to assist with the explicit inclusion of ?sustainability? in the decision-making processes of those responsible for providing water services. The book contains a framework that comprises a set of decision support processes that can be used by water service providers to explicitly incorporate sustainability considerations into their decision-making procedures, through the use of sustainability principles, criteria, indicators and processes. These principles and criteria can be applied at an overall corporate strategic level, for example in the service provider?s mission statement, or at an application level, where these strategic principles are being applied to a particular decision. Sustainable Water Services is designed to inform and to provide support for strategic activity, both as a resource containing information about sustainability, and by employing feedback from application to inform the strategic processes of the water service provider. Presents an inclusive and generic set of sustainability criteria for use in water industry decision making processes; Discusses the legislative drivers for sustainable decision making for the UK water industry; Presents clear case study examples of the sustainability framework in action; Discusses the use and applicability of a wide range of tools and techniques for undertaking environmental, economic and social analyses, e.g. life cycle assessment, multi-criteria analysis.

One approach to the introduction of computational material to the classroom is to supplement a textbook with modern computer codes. Unfortunately most codes are expensive, designed for commercial use, without source code and may require special software. Visual Hydrology provides a cheaper and simpler alternative, supplying computational exercises that can be fully assimilated by students, and allowing them to activate, understand and reproduce modern computer code. Visual Hydrology aims to: explain the structure of modern object-oriented computer code provide the source code for worked examples numerically check the worked examples used in text show how worked examples can be used with alternative data describe and reference the underlying theory provide additional exercises with each worked example use Microsoft Excel software alone Requiring only a basic knowledge of Microsoft Excel, this Primer teaches the use of modern and readily-available computer code for engineering computation. Visual Hydrology demonstrates codes for common and practical examples used in hydrological engineering, and will be a valuable resource to students, research workers and consulting engineers in the water-related sector. Examples of source code to accompany this publication can be downloaded by clicking here.

Instrumentation, control and automation (ICA) in wastewater treatment systems is now an established and recognised area of technology in the profession. There are obvious incentives for ICA, not the least from an economic point of view. Plants are also becoming increasingly complex which necessitates automation and control. Instrumentation, Control and Automation in Wastewater Systems summarizes the state-of-the-art of ICA and its application in wastewater treatment systems and focuses on how leading-edge technology is used for better operation. The book is written for: The practising process engineer and the operator, who wishes to get an updated picture of what is possible to implement in terms of ICA; The process designer, who needs to consider the couplings between design and operation; The researcher or the student, who wishes to get the latest technological overview of an increasingly complex field. There is a clear aim to present a practical ICA approach, based on a technical and economic platform. The economic benefit of different control and operation possibilities is quantified. The more qualitative benefits, such as better process understanding and more challenging work for the operator are also described. Several full-scale experiences of how ICA has improved economy, ease of operation and robustness of plant operation are presented. The book emphasizes both unit process control and plant wide operation. Scientific & Technical Report No. 15

Drinking water provides an efficient source for the spread of gastrointestinal microbial pathogens capable of causing serious human disease. The massive death toll and burden of disease worldwide caused by unsafe drinking water is a compelling reason to value the privilege of having safe drinking water delivered to individual homes. On rare occasions, that privilege has been undermined in affluent nations by waterborne disease outbreaks traced to the water supply. Using the rich and detailed perspectives offered by the evidence and reports from the Canadian public inquiries into the Walkerton (2000) and North Battleford (2001) outbreaks to develop templates for understanding their key dimensions, over 60 waterborne outbreaks from 15 affluent countries over the past 30 years are explored as individual case studies. Recurring themes and patterns are revealed and the critical human dimensions are highlighted suggesting insights for more effective and more individualized preventive strategies, personnel training, management, and regulatory control. Safe Drinking Water aims to raise understanding and awareness of those factors that have most commonly contributed to or caused drinking-water-transmitted disease outbreaks - essentially a case-history analysis within the multi-barrier framework. It contains detailed analysis of the failures underlying drinking-water-transmitted disease epidemics that have been documented in the open literature, by public inquiry, in investigation reports, in surveillance databases and other reliable information sources. The book adopts a theme of 'converting hindsight into foresight', to inform drinking-water and health professionals including operators, managers, engineers, chemists and microbiologists, regulators, as well as undergraduates and graduates at specialty level. Key Features: Contains details and perspectives of major outbreaks not widely known or understood beyond those directly involved in the investigations. Technical and scientific background associated with case studies is offered in an accessible summary form. Does not require specialist training or experience to comprehend the details of the numerous outbreaks reviewed. By providing a broad-spectrum review using a consistent approach, several key recurring themes are revealed that offer insights for developing localized, tailor-made prevention strategies.

What are the rules of international water law that govern the use of the transboundary aquifers shared by Palestine and Israel? This book addresses this issue through an interdisciplinary approach, identifying first the special problems tied to the management of shared groundwater, and next critically analysing the applicable rules of international law. The innovative contribution of this work is its attempt to devise and suggest the means to implement a "e;progressive framework"e; for cooperation in the development and management of these shared waters. A solid review of hydro-politics, supported by current up to date information and rigorous examination of the evolution of the relevant rules of international law makes this book an important contribution to this very problematic area. Dr Fadia Diabes-Murad was awarded the Edberg Award 2005, presented at a special awards ceremony in Stockholm. The award recognised her contribution to peace in the Middle East through her work on water law, including using water as a catalyst for peace in the Middle East.

Implementing the goal of sustainable development has long been heralded as the means by which the needs of both present and future generations can be met. However, finding a long-term balance between economic, social and environmental interests, the basic tenet of sustainable development, has proved largely illusive in practice. This book shows that while a number of legal frameworks to help promote the goal of sustainable development have been proposed at the international level they fail to fully capture the essence of sustainable development and international law's capacity to support its implementation. The book offers a critical analysis of past attempts to develop legal frameworks for promoting sustainable development at the international level, and advocates for a fresh approach based on lessons learnt from the law of international watercourses. The book is divided into four sections. The first section includes an overview of the topic area and an understanding of international law. In section two the book explores the meaning of sustainable development and considers the term's relationship with international law. A detailed analysis of how the law of international watercourses seeks to reconcile competing economic, social and environmental interests is carried out in section three. The book concludes with a section advocating the need for a fresh approach to international law and sustainable development and offering the foundations for this approach based on lessons learnt from the law of international watercourses.

Competition and Economic Regulation in Water: The Future of the European Water Industry reviews the main developments in economic regulation and competition in the European water industry and considers ways in which economic regulation and competition should be further developed. The book focusses on the best means of regulating or introducing competition into the industry in light of its present structure. Competition and Regulation in Water: The Future of the European Water Industry concentrates on the water industry, however, many of the conclusions are equally applicable also to the wastewater industry. Contents Introduction Water industry fundamentals: the rationale for regulation and the scope for competition A framework for evaluating different models of water industry regulation England & Wales: private ownership and independent regulation France: competition for the market and contract-based regulation Germany: public-private partnerships and multi-sector utilities Developing water sector regulatory frameworks in less developed countries Appendix: The legislative framework for the water industry in England & Wales

This comprehensive reference, dealing with municipal wastewater management in developing countries, is prepared by leading international authorities, and will provide an invaluable reference for all those concerned with the management of sanitation services in developing countries worldwide.

Water meters are the cornerstone of commercial systems for water utilities throughout the world; revenue is directly derived from the, figures provided by meters. Despite this, little attention has been paid, in terms of selection, replacement period and return on investment, to the management and optimization of water meters. Integrated Water Meter Management is a comprehensive reference for engineers and managers alike, providing: in-depth technical information allowing the true nature and behaviour of meters to be understood; a comprehensive review and comparison of relevant global water meter technologies - a useful tool to help decide which water meter is best for your utility; discussion of key decisions concerning the use of water meters (when to replace them, which one to use, how to control their quality) from a managerial perspective. Integrated Water Meter Management is an invaluable resource for those involved in urban water management, including water utility managers, engineering technical staff, operations and maintenance specialists, meter-reading personnel and scientific researchers in this discipline.

Biological wastewater treatment plants can be adversely affected by influent toxicity. The effects can range from poor clarifier biomass settling and elevated effluent BOD and ammonia levels to total plant kills. These problems could be minimized or eliminated if an effective method existed for continuously monitoring biological wastewater treatment plant influent for toxicity to the treatment plant microorganisms. Current influent screening methods have not been proven to be adequate for adaptation to continuous screening in the field. The primary reasons include the batch-wise nature of the assays and an inadequate correlation between the assays and plant performance. The goal of the research team was to create new bioluminescent biosensors from different types of bacteria found in biological wastewater treatment plants for the development of a multi-channel continuous monitoring system. A system built from multiple biosensors would make it possible to differentiate between potential influent toxicity effects to different classes of bacteria (such as nitrifying and heterotrophic bacteria). The research team found it unexpectedly challenging to apply common microbiological transformation methods for laboratory strains to the wastewater treatment plant strains. The research team generated six new bioluminescent bioreporters from bacteria that are typical constituents of activated sludge. Of particular significance is a bioreporter developed using a Hyphomicrobium sp., which is a slow growing bacterium known to be present in significant numbers in some activated sludge plants. Of the six generated, initial bioluminescence and toxicity screening indicated that one strain (a Pseudomonad) was a particularly promising candidate due to its ease of cultivation and high light production. Further toxicity testing, however, determined that the response of the strain to 48 organic compounds and 8 metals commonly found in wastewater was similar to that of a previously created strain, Shk1 (also a Pseudomonad). Further work is therefore needed in the generation of appropriate biosensors and test conditions for populations not represented by the new heterotrophic biosensor.

This investigation reviewed and evaluated methodologies used for microbial risk assessment with respect to their applicability for reclaimed water applications. The investigation was comprised of five primary components: a comprehensive database of articles, reports and books describing microbial risk assessment methodologies was established and reviewed. Risk assessment techniques and models were identified for estimating the public health risk from exposure to microorganisms via reclaimed water applications. Two models were identified for further evaluation: a static (individual based) and a dynamic (population based). In the third component, the two models were evaluated to differentiate between the conditions under which models predict similar and substantially different estimations of risk. Through numerical simulation, exposure/pathogen combinations were identified when it may be appropriate to use the less complex, static model. Case study risk assessment scenarios demonstrated the model selection process for three realistic, yet hypothetical reclaimed water scenarios.The fourth component presents a constraint analysis for existing reuse regulations. The constraint analysis is carried out by documenting the existing reuse regulations. The constraint analysis is carried out by documenting the existing regs in three states for landscape irrigation and uses that comparison as a starting point to identify how microbial risk assessment may be useful within the context of existing and potential future water reuse regulations. The investigation concludes by identifying criteria for a computer interface that would allow regulatory and/or municipal agencies/utilities to take advantage of the analysis discussed in the report. This publication can also be purchased and downloaded via Pay Per View on Water Intelligence Online - click on the Pay Per View icon below

The sequencing batch reactor (SBR) is perhaps the most promising and viable of the proposed activated sludge modifications today for the removal of organic carbon and nutrients. In a relatively short period, it has become increasingly popular for the treatment of domestic and industrial wastewaters, as an effective biological treatment system due to its simplicity and flexibility of operation. Mechanism and Design of Sequencing Batch Reactors for Nutrient Removal has been prepared with the main objective to provide a unified design approach for SBR systems, primarily based on relevant process stoichiometry. Specific emphasis has been placed upon the fact that such a unified design approach is also by nature the determining factor for the selection of the most appropriate cyclic operation scheme, the sequence of necessary phases and filling patterns for the particular application. The proposed basis for design is developed and presented in a stepwise approach to cover both organic carbon and nutrient removal, domestic and industrial wastewaters, strong and specific wastes. The merits of model simulation as an integral complement of process design, along with performance evaluation of SBR models are also emphasized. Scientific and Technical Report No. 19