Linking theory and application in a way that is clear and understandable, Groundwater Lowering in Construction: A Practical Guide to Dewatering, Second Edition uses the authors’ extensive engineering experience to offer practical guidance on the planning, design, and implementation of groundwater control systems under real conditions.
Discover engineering methods that can help you improve working conditions, increase project viability, and reduce excavationcosts.
In the decade since publication of this book’s first edition, groundwater lowering and dewatering activities have been increasingly integrated into the wider ground engineering schemes on major excavations to help provide stable and workable conditions for construction below groundwater level. Consequently, many engineering ventures now require a more in-depth assessment of potential environmental impacts of dewatering and groundwater control, and this book details the latest best practices to evaluate and address them.
Includes New Chapters Covering:
- Cutoff methods used for groundwater exclusion
- Issues associated with permanent or long-term groundwater control systems
- Groundwater control technologies used on contaminated sites
- Methods needed to understand, predict, and mitigate potential environmental impacts of groundwater control works
Updated to reflect the crucial technological and application advances shaping construction processes, this book contains valuable direction that can give you a true competitive advantage in the planning and execution of temporary and permanent dewatering works. The authors cover cutting-edge methods and key subjects, such as the history of dewatering, working on contaminated sites, site investigation techniques, and operation and maintenance issues, including health, safety, and legal aspects. Written for practising engineers and geologists as well as postgraduate engineering students, this updated manual on design and practice provides numerous case histories and extensive references to enhance understanding.
Table of Contents
Groundwater lowering: A personal view, P.Cashman
Structure of the rest of the book
History of groundwater theory and practice
Earliest times to the sixteenth century
Renaissance period to the nineteenth century
Progress from a qualitative to a quantitative science
Later theoretical developments
Early dewatering technology in Britain
Groundwater and permeability
Hydrology and hydrogeology
Permeability and groundwater flow
Aquifers, aquitards, and aquicludes
Flow to wells
Aquifers and geological structure
Using geological structure to advantage
Groundwater effects on the stability of excavations
Groundwater control—the objectives
Groundwater, effective stress, and instability
Large-scale instability caused by groundwater
Localized groundwater problems
Excavations in rock
Surface water problems
Effect of climate and weather
Methods for control of surface water and groundwater
Control of surface water
Methods of groundwater control
Groundwater control for tunnels and shafts
Use of pumping and exclusion methods in combination
Site investigation for groundwater lowering
Purpose of site investigation
Planning of site investigations
Stages of site investigation
Determination of ground profile
Determination of groundwater conditions
Determination of permeability
Design of groundwater lowering systems
What is design?
Development of a conceptual model
Expectations of accuracy
Selection of method and geometry
Estimation of steady-state discharge flow rate
Specification of well yield and spacing
Applications of sump pumping
Pumping of surface water runoff
Drainage of side slopes of an excavation
Sump pumping of small excavations
Sump pumping problems
Disposal of water from sump pumping operations
Case history: Sump pumping of large excavation
Which system: Wellpoints or deep wells?
What is a wellpoint system?
Wellpoint installation techniques
Spacing of wellpoints and drawdown times
Sealed vacuum wellpoint system
Wellpoint pumping equipment
Wellpoint installations for trench excavations
Wellpointing for wide excavations
Wellpointing for deeper excavations
Case history: Derwent outlet channel, Northumberland
Deep well systems
Deep well installations
Design of wells for groundwater lowering
Constructing deep wells
Drilling of well boreholes
Installation of well materials
Installation and operation of deep well pumps
Vacuum deep well installations
Shallow well installations
Case history: Tees barrage, Stockton-on-Tees
Other dewatering systems
Pressure relief wells
Artificial recharge systems
Dewatering and groundwater control technologies used for the control or remediation of contaminated groundwater
Methods for the exclusion of groundwater
Principal methods for groundwater exclusion
Geometries of exclusion applications
Steel sheet piling
Vibrated beam walls
Slurry trench walls
Concrete diaphragm walls
Bored pile walls
Artificial ground freezing
Pumps for groundwater lowering duties
Pumps for deep wells
Sizing of pumps and pipework
Permanent groundwater control systems
Types of permanent groundwater control systems
Objectives of permanent groundwater control systems
Design issues for permanent groundwater control systems
Practical issues for permanent groundwater control systems
Opportunities associated with permanent groundwater control systems
Case history: Govan underground tunnel, Glasgow
Environmental impacts from groundwater control
Why are impacts from groundwater control of concern?
Potential environmental impacts from groundwater control
Impacts from groundwater abstraction
Impacts from groundwater pathways
Impacts from groundwater barriers
Impacts from discharge flows to the groundwater environment
Impacts from discharge flows to the surface water environment
Assessment of potential environmental impacts
Monitoring and maintenance of groundwater lowering systems
Need for monitoring
Monitoring of water levels
Monitoring of discharge flow rate
Other parameters that may be monitored
Mechanical factors and automation
Backfilling and sealing of wells on completion
Encrustation, biofouling, and corrosion
Fault finding and problem solving
Safety, contracts, and environmental regulation
Health and safety
Contracts for groundwater control works
The future—a personal perspective by Toby Roberts
Applications and techniques
Communication and monitoring technology
Where do we go from here?
Next generation of dewatering practitioners
Appendix 1: Estimation of permeability from laboratory data—Loudon method
Appendix 2: Execution and analysis of variable head permeability tests in boreholes
Appendix 3: Execution of well pumping tests
Appendix 4: Design examples
Appendix 5: Estimation of flow rate using V-notch weirs
List of notation
List of conversion factors
Prior to his death in 1996, Pat Cashman was the leading British exponent of groundwater control for his generation. For more than 40 years, during the growth of soil mechanics into the practice of geotechnical engineering, Pat was responsible—through the organisations he ran, and later as a consultant—for maintaining a practical and straightforward approach to the art of groundwater control.
Dr. Martin Preene is a highly experienced geotechnical engineer specializing in groundwater engineering and hydrogeology. Martin has more than 25 years of experience working with contractors and consultants on the design and implementation of dewatering and groundwater control systems. He has worked on major engineering projects around the world, including power stations, road and railway tunnels, dry docks, and open-pit mines. He is widely published on dewatering and groundwater engineering, including papers and industry guidance documents. Dr. Preene is currently a principal at Golder Associates in the UK.
"An essential and highly practical tool for all hydrogeologists and geotechnical and civil engineers involved in the quantified design and planning, construction, monitoring, operation, decommissioning, regulation and assessment of environmental impacts of groundwater lowering and dewatering systems."
––Trevor Muten in Quarterly Journal of Engineering Geology and Hydrogeology
"The word ‘practical’ is in the sub-title and that very much reflects the approach throughout: much of the content is based on four decades of experience in groundwater lowering projects throughout the world… The main difference from the previous edition is the introduction of a chapter on the environmental effects of dewatering, reflecting increased societal and regulatory focus on these aspects. However, new sections on cutoff methods, long-term systems and contaminated land all reflect developments in the industry over this period."
–– Mike Streetly in Quarterly Journal of Engineering Geology and Hydrogeology
"This is the book that the dewatering sector really needs—it is reliably based on sound theory and profound understanding of the physical processes, yet is presented in a very accessible and user-friendly manner. It draws on many, many decades of experience, and yet is utterly up to date, even including an intriguing glimpse into the future at the end of the book. With the addition of new material on cut-off methods for groundwater exclusion, permanent dewatering installations and groundwater control on contaminated sites, this book really does now cover all of the bases for the modern-day practitioner. It is a one-stop shop for the dewatering practitioner—who can nonetheless rest assured that the theoretical basis of the methods presented is flawless."
—Professor Paul L. Younger, FGS, FICE, C.Geol., C.Eng., FREng, University of Glasgow, Scotland, UK
"The best reference on this topic available...and will prove useful to a wide variety of readers ranging from junior construction engineers or dewatering contractors to theoretical hydrogeologists and environmental managers. It is rare that a book is able to bridge the gap between theoretical design guidance and practical application."
"The book provides an excellent and practical account of many aspects of dewatering in construction, usefully including a detailed discussion of permanent groundwater control systems. It provides a good account of basic hydrogeology and the history of the development of the science, and includes a thorough chapter on site investigations for dewatering design. Dewatering design and the installation and operation of various types of dewatering system are described in detail, making the book an excellent resource, both for practical purposes and for training. Each chapter has a good reference list for further, more detailed reading. I certainly recommend the book for both practitioners and teaching institutions."
—John Waterhouse, Golder Associates Pty Ltd, West Perth, Australia
"[This second edition] takes a well received and respected book on this niche subject and brings it fully up to date. "
—David Richards, University of Southampton, UK
"I believe that this book will be a useful update of the earlier edition and provides a practical guide to dewatering systems. … up-to-date information on equipment and regulations.
"—Prof Rick Brassington, Newcastle University/Independent Consultant, Culcheth, Warrington, UK
Praise for the First Edition
"As a practising engineer I feel this book will be extremely useful whenever I encounter any groundwater issues in the future. Any engineer (or contractor) will appreciate the non-technical style of the writing that makes extracting required information from the text easy. I am sure this book will rapidly become dog-eared and regularly borrowed from my office. If you can only have one text on groundwater in your shelf this would be an excellent candidate for the job."
—New Zealand Geomechanics News
"I am pleased to recommend this book to all those who have any interest in groundwater control—whether as a practitioner of groundwater control, a design or site engineer involved in construction, or as an environmental manager."
—Journal of the Chartered Institute of Water and Environmental Management
"An invaluable addition to the library of anyone working in this field."
––Quarterly Journal of Engineering Geology and Hydrogeology