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THE CHALLENGE OF WATER TREATMENT PLANT DESIGN 1.5

4. Final design. Contract documents (drawings and specifications) are prepared that
present the project design in sufficient detail to allow for gaining final regulatory ap-
provals, obtaining competitive bids from construction contractors, and actual facility
construction.
Many technical and nontechnical individuals must be involved, not only during the
four phases of project development, but also between these phases to ensure that a proj-
ect proceeds without undue delay. In addition to the engineer's design staff and the owner,
these may include public health and regulatory officials, environmental scientists, and the
public affected by both the proposed construction and the future water supply services to
be provided.
The process train selection phase is only briefly covered in this book. Theory and pro-
cedures needed for this phase are the focus of Water Quality and Treatment. It is impor-
tant that the interface between phase 1 and phase 2 and between phase 2 and phase 3 be
carefully coordinated to allow uninterrupted continuity of design. In other words, viable
options developed for consideration in phase 1, master planning, should provide a base
for developing unit process test studies in phase 2. The process train selected in phase 2
provides the basis for phase 3, preliminary design, in which other factors influencing de-
sign are included in the evaluations before criteria for final design are developed and
finalized.
Careful coordination of the various phases and entities involved provides the owner
and the engineer with the opportunity to develop the most advantageous treatment solu-
tions and designs, and helps avoid pitfalls in the schedule and decisions that might add
to the cost of the project.

THE PURPOSE OF THIS TEXT

Water Treatment Plant Design is intended to serve as the primary reference for engineers
who take on today's challenges of water treatment plant design. It covers the organiza-
tion and execution of a water treatment plant project from planning and permitting through
design, construction, and start-up.
The book is aimed at "project" engineers and managers: those professional engineers
who lead the group of specialists who make up the design team. Generally, these indi-
viduals are graduates of civil or environmental engineering programs and are registered
professional engineers.
For certain topics, especially the practical application of water treatment unit processes,
this book aims to be an authoritative reference to design engineers. For other topics, only
a general discussion of major concepts and issues is provided, and the reader is referred
to more specialized references for detailed information.
Many books in circulation address the subject of water treatment engineering. As a
joint publication of the American Society of Civil Engineers (ASCE) and the American
Water Works Association (AWWA), Water Treatment Plant Design attempts to present
an industry consensus on current design practices.

Organization of This Text

For the convenience of readers, chapters in this book have been organized as follows:
• Chapters 1, 2, and 3 examine the general preliminary and final design phases and en-
gineering needs during project construction and initial operation.