Construction Management at Risk - Design-Build for Water and Wastewater Projects - page 307

Figure 25-3. The Impact of design changes on project costs during the design and
construction of a project
It is important to remember that changes cause the least amount of impact the earlier
they are implemented, as illustrated in Figure 25-3. To manage this process effectively,
the owner will need to proactively review the recommendations from the CMAR firm,
the designer's responses to those recommendations, and the potential financial impact
of the recommendations on the cost of design and construction of the project, as well as
the project schedule. Constructability reviews by the CMAR firm can range from very
informal plan reviews by construction experts and designers, to very comprehensive and
formal value engineering reviews.
Overseeing Design and Construction
CMAR projects, unlike progressive or fixed-price DB, place the responsibility of process
performance on the owner. A well-planned quality assurance (QA) program with defined
quality control (QC) procedures will help to mitigate the risk of process performance and
ensure the project is constructed to the owner's requirements. Contracts often specify proj-
ect requirements and quality criteria, but with the designer and CMAR firm each contracted
separately to the owner, it becomes the owner's role to establish the QA/QC responsibilities
for the designer and CMAR to ensure complete project coverage (WDBC 2010).
Managing Design Changes
Because CMAR delivery requires that the owner hold separate contracts for both design
and construction, the owner is exposed to a higher risk of change orders than in DB deliv-
ery. The nature of water and wastewater projects can result in significant changes during
the execution of the work; therefore, a detailed change management plan is necessary to
identify potential trends and changes, assign ownership to the issue, track progress, and
ensure that a timely resolution is achieved.