Western Riverside County Regional Wastewater Authority

Third-Party Construction Management for Unique Design/Build Project

Carollo provided third-party construction manage-ment services on a unique design-build project for the Western Riverside County Regional Wastewater Authority (WRCRWA). The project included construction of a new 8-mgd tertiary treatment facility that meets stringent discharge guidelines for the Santa Ana River. In an effort to control costs, the WRCRWA was interested in a different approach to project delivery than the traditional design, bid, construct method.
 
Alternative Project Delivery
The WRCRWA adopted a design/build concept and selected Carollo to provide construction management and design/review services. The most unique feature of the design/build concept was the substitu-tion of bid document specifications with specifica-tions developed by the contractor’s design engineer during the first four to six months of the construc-tion period.

Project Elements
The project includes a headworks, biological second-ary treatment, solids handling, and tertiary treatment. Secondary treatment includes a Carrousel process with anoxic chambers for nitrogen removal and gravity return to recycle mixed liquor. Aerobic digestion and centrifuges are used to stabilize, thick-en, and dewater solids. The facility provides tertiary treatment in conformance with California’s Title 22 requirements.

Team and Services
Carollo’s construction management team provided issue resolution procedures, design review, review/approval of "or equal" substitution specifications, and quality control. In addition to a full-time construction manager, the construction management team included an on-site resident engineer and specialty inspectors. A key feature of the team was the dual design and construction management expertise of the construction manager and resident engineer. The construction management team identified issues and established procedures during the review/approval process to move the project from owner-furnished to contractor-furnished design. Expedition software helped to manage submittals, requests for information, change orders, correspondence, and all other related documents.

With WRCRWA providing overall direc-tion, Carollo used a partnering approach to construction management to establish goals and promote teamwork. Through partnering updates, our construction management team maintained excellent communication with all stakeholders in the project.


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