Commissioning and Acceptance Testing - Design-Build for Water and Wastewater Projects - page 289

Plant Reliability and Life-Cycle Cost
Along with demonstrating that the quality of the treated water is acceptable, acceptance
testing sometimes also requires demonstration that the plant operates reliably, with a rea-
sonable number of operators and at an acceptable cost for power and chemicals.
Careful consideration of these operational requirements and methods to demonstrate
compliance is required. Some treatment facilities use proprietary or costly chemicals, and
reliability problems can cause higher chemical use, for example, if a pretreatment system
is found to be unreliable. Low-pressure or high-pressure membrane systems will need to
be chemically cleaned more frequently. The cleaning cycle is often guaranteed by the sys-
tem suppliers and requires from 30 days (typical for low-pressure) to 3 months (typical for
high-pressure systems). Testing periods are often extended so that the cleaning frequency
is tested, and thus the reliability of the pretreatment is known.
REGULATORY INVOLVEMENT
Regulatory agencies are not typically interested in the commissioning activities; however,
they are sometimes very interested in how acceptance testing is performed, and their level
of interest is based on the health or environmental risk posed by treatment, the number of
similar installations in operation, and the owner's record of compliance on previous projects.
REFERENCES
Canney, S. 2006. Perspective on Performance Guarantees. Design-Build Dateline, Design-
Build Institute of America, January.
Design-Build Institute of America (DBIA). 2008a. Design-Build Manual of Practice, Docu-
ment Number 209, Process Industries Best Practices. Washington, D.C.: Design-Build
Institute of America.
DBIA. 2008b. Design-Build Manual of Practice, Document Number 303, Executing the
Design-Build Project. Washington, D.C.: Design-Build Institute of America.
Water Design Build Council (WDBC). 2010. The Municipal Water and Wastewater Design
Build Handbook, 2nd ed. Washington, D.C.: Water Design-Build Council.
White, T. J., T. Larson, and S. Schebler. 2009. Innovative Solutions to Challenging Com-
missioning and Startup at the Lake Pleasant WTP. In Proceedings of the Design-Build
Institute of America's Water/Wastewater Conference, Denver, Colo., March 4-6. Wash-
ington, D.C.: Design-Build Institute of America.