Page 48 - Water and Wastewater Engineering Design Principles and Practice

THE DESIGN AND CONSTRUCTION PROCESSES 1-19

requirements because an initial assumption to start the design is not valid. For example, a pipe
diameter may be assumed to carry an estimated flow rate. The selection of this pipe diameter may
not be large enough based on friction loss calculations. Thus, a larger pipe must be selected, and
a second friction loss calculation must be completed.

1-6 OVERALL CONSTRUCTION PROCESS
From the owner’s perspective, the construction process has the following important steps or
stages:

• Initiation of project financing arrangements.
• Acquisition of land or easements.

• Project design.
• Completion of project financing.
• Bid letting.
• Construction.

• Preparation of project record documents.
• Preparation of the O&M manual.
• Start-up and shake-down.
• Acceptance of the project.

The owner’s perspective is taken because the contracts for construction are with the owner
and, ultimately, the facility belongs to the owner, not the engineer. None the less, the engineer’s
role is critical because he/she must diligently observe and, to the best of their ability, assure the
owner that the facility is built according to the plans and specifications.
The construction process should not begin before the design process and project financing
are complete. Practicing engineers recommend that with the classical design-bid-construct proj-
ect delivery, construction not begin until the design is complete. Other delivery methods, such
as design-build, may begin the construction process before the design is complete. Although
starting before the design is complete expedites the process, it imposes a need for extreme care
in making commitments.

Project Financing
The funds to pay for the project may come from a variety of sources. Bonds, state aid funds, oper-
ating revenue, and user fees are some examples. Discussion of these are beyond the scope of this
book. They are discussed at length in Water Utility Capital Financing (AWWA, 1998).

Acquisition of Land or Easements
Once the study phase is completed, enough information is available to begin identifying suit-
able sites for the project and, in the case of sewers and other utilities, routes for easements.