How Pre-Procurement Can Overcome Constraints on Wastewater Infrastructure Projects

Dudek engineers successfully administered variations of pre-procurement processes to shorten construction schedules while controlling costs and project risks on three recent wastewater infrastructure projects.

Focusing on unique project needs, Dudek used three progressively complex pre-procurement methods: pre-selection, pre-approval, and pre-purchase of equipment and materials. Each approach was carefully administered within specific exceptions to California’s Public Contract Code that governs competitive bidding practices for public agencies, allowing owners more definitive material selections than the conventional “or equal” or performance specification process.

When correctly used, pre-procurement can control costs and ensure the quality of equipment and materials while reducing the risks of conflicts and claims during construction.

Pre-procurement of equipment or materials requires that construction bidding and contract documents be structured differently than for a conventional design-bid-build project. Because the owner assumes responsibility for pricing of pre-selected items, it is imperative that the engineer and owner negotiate a firm, guaranteed price with the pre-selected manufacturers prior to public bidding.

In addition to the negotiated pricing, the bid documents must convey to the construction contractor the purchase “terms and conditions” on which the negotiated pricing was based. In the case of pre-purchased items, the transfer of responsibility for “owner-furnished” materials must be clearly defined. Thorough specifications and special conditions will reduce potential issues arising during construction between parties.

Following are overviews of the three successful projects.

Pre-Selection of Unique Equipment at the Encina Water Pollution Control Facility

Encina Wastewater Authority hired Dudek to rehabilitate four 105-foot diameter secondary clarifiers at its 45 million gallons daily (mg) wastewater treatment plant in Carlsbad.

In consultation with Encina staff, Dudek engineers determined that pre-selection of the clarifier mechanisms was necessary to match desired features of other existing clarifiers while controlling costs and schedule in construction. The engineers performed thorough site investigations, developed detailed technical specifications, and administered contract negotiations with the preferred equipment manufacturer.

Key to project success was carefully structured bid documents that clearly defined the negotiated terms and conditions including delivery schedule and warranties. During construction, Dudek engineers worked closely with the manufacturer and installing contractor to verify field conditions, approve shop drawings, commission the clarifier system, and exercise warranty calls.

Pre-Approval of Major Equipment for City of Guadalupe Wastewater Treatment Plant

The project to improve the 0.96-mgd treatment plant faced an almost insurmountable short delivery schedule stipulated by the funding agency that placed the $4.5 million grant in jeopardy.

After thorough review of the project schedule, Dudek engineers identified that the early critical path of the construction phase was predominated with procurement of three major equipment packages. The Dudek project manager presented the city and funding agency with an accelerated schedule that included pre-procurement of long lead-time equipment items, concurrent with completion of final design, demonstrating a reduction in the construction schedule from twelve to eight months.

After soliciting competitive proposals from previously qualified equipment manufacturers, Dudek administered selection of the lowest, responsive equipment package(s). The procurement process incorporated deposits issued by the city to authorize the manufacturers to prepare shop drawings, which allowed the construction bid documents to include pre-approved submittals. The successful construction bidder issued a purchase order and released the equipment for manufacture immediately upon receiving the Notice to Proceed – effectively shaving at least three months off the construction schedule.

Pre-Purchase Packaged Equipment at City of Laguna Beach Main Beach Lift Station

On-site construction was restricted to the nine-month tourist off-season (September to May). In consultation with city staff, Dudek engineers initiated a pre-selection process to choose a packaged lift station manufacturer during the preliminary design phase.

The engineers worked closely with the manufacturer to develop a custom design addressing project constraints such as limited construction access and construction period, groundwater impacts, and the city’s design standards and preferences.

With these details resolved, pre-purchase of the lift station package was negotiated to ensure that all materials were delivered to the site prior to start of construction. In this case, careful coordination was required between the pre-purchased equipment package and the construction bid documents. Special conditions were incorporated to define the transfer of responsibility for pre-purchased items from the owner to the contractor during construction.