Value Engineering - Design-Build for Water and Wastewater Projects - page 253

(38-ML/d) microfiltration membrane treatment facility with a budget of $18 million. Due
to long projected lead time of the microfiltration membranes, the City initiated early pro-
curement for the membranes.
As design progressed to the 30 percent design completion level, cost estimates began
to escalate, and by the completion of the 30 percent design completion, a construction
budget of $27 million was anticipated. Westminster elected to procure the plant on a price
competitive DB basis. Using this model, the owner provided prospective design-builders
boundaries for the projects requirements, conceptual design documents, and information
regarding prepurchased membranes that were to be incorporated into the project. Pro-
spective design-builders were required to conduct VE on the 30 percent design comple-
tion, prepare a technical proposal based on the value engineered design, and provide a
firm, fixed price for the technical approach presented.
The successful DB team implemented VE in the development of its proposal to
achieve a competitive advantage. Although the VE analysis was informal, the successful
design-builder was able to achieve higher functionality at a lower cost, thus improving
value.
The process design uses enhanced conventional treatment with plate settlers followed
by microfiltration membrane units. This alternative was proposed by the design-build
team to increase plant capacity by 50 percent. The DB team also substantially modified
the original building layout to produce a more cost-effective project.
Westminster is an excellent example of implementing VE practices when DB pro-
curement is done under a best-value selection (i.e., technical and price competition selec-
tion criteria) where owner input is limited in the development of the technical approach
and price. The DB team anticipated that the owner would want to participate in additional
VE decisions and processes subsequent to the selection. To accommodate this, the DB
team identified a number of potential VE alternatives and provided a matrix of pricing for
those alternatives. This approach left placeholders in the bid price for future VE decisions.
Through the application of VE practices the DB team was able to offer the owner sub-
stantially more capacity (i.e., 50 percent) with a 25 percent reduction in overall cost. The
owner reported that “Our design-build team is building a 15 mgd (57 ML/d) plant for 75
percent of what we had originally anticipated spending on a 10 mgd (38 ML/d) facility.”
Aquifer Storage and Recovery Project Example
Since the mid-1950s, the City of Wichita Kan., has been vulnerable to water shortages
during drought conditions. This vulnerability is compounded by the decline of the
Equus Beds Aquifer, the City's primary water supply. In 1993, the City developed an
Integrated Local Water Supply Plan that considered numerous approaches to preserving
and expanding its water supply. One component of the Integrated Local Water Supply
Plan is the restoration and reuse of the Equus Beds Aquifer through aquifer storage and
recovery (ASR). Implemented in several phases, the City will construct up to 100 mgd
(378 ML/d) of water recharge and recovery capacity. The City is now in the second phase
of the program, which includes the construction of a 60-mgd (227-ML/d) river intake
and 30-mgd (114-ML/d; expandable to 60-mgd) surface water treatment facility. Excess
surface water is drawn from the Little Arkansas River while the river is above base flow,
treated with an advanced oxidation/membrane filtration process, and injected into the