City officials of Guadalupe, CA recently completed the successful upgraded of its wastewater treatment plant, securing state grant funding for the project by adhering to a tight completion schedule and using innovative procurement methods.
Dudek engineers assisted the city by designing the major plant upgrade, administering the $4.5 million Proposition 50 grant, and assisting during construction.
The design upgrades brought the 0.96 million gallons per day (mgd) into compliance with its existing state Waste Discharge Requirements. The plans converted a failing pond treatment system into a new extended aeration biological process with provisions for nitrogen removal. Other improvements included retrofit of the headworks with a new influent bar screen, sludge dewatering facilities, and a new emergency standby generator.
Complicating the project delivery was the shortened design and construction schedule. The project had been placed on hold in late 2010 pending approval by the state of the final project components. In May 2011, the state approved the project scope but unexpectedly denied the city’s request to extend the grant deadline. At the risk of forfeiting the critical grant funds, the project needed to be fast-tracked, progressing from 30% design plans to plant construction and start-up in less than 12 months.
To meet this schedule, Dudek and the city developed a “project implementation plan” allowing final design and equipment procurement to proceed in parallel, saving at least three months. Dudek engineers solicited competitive proposals for pre-procurement of major, long lead-time equipment items and selected, approved, and pre-negotiated firm-guaranteed prices with fixed delivery schedules prior to completion of final design.
Dudek also shortened the normal design schedule, producing the bid package in three months and incorporating fast-track conditions to facilitate an eight-month construction period. Customized specifications included interim milestones with liquidated damages to ensure progress while allowing the general contractor 24/7 access to the site to meet the defined schedules. The successful low bidder, Spiess Construction, worked 10-hour days, six days a week through much of the construction period to meet the grant deadline.
Dudek’s design team and the city’s construction management team, Canon Associates, were in constant communication throughout the construction phase and provided priority attention to contractor requests for information, submittals and the inevitable field construction changes.
City Had Only One Shot to Bid – Accurate Cost Estimates Were Essential
The impending grant funding deadline meant the city had one chance to successfully complete a public bid. If an award could not be made for any reason, the time lost would have jeopardized the funding and effectively killed the project. Therefore, accurate estimates and cost controls were crucial to moving forward with bidding.
To ensure estimated costs were accurate, Dudek engineers:
- Carefully reviewed the construction cost estimates, verified quantity take-offs, consulted with specialty contractors, and continuously refined their estimating methods.
- Created a cost-estimate database at the beginning of the project that was continuously updated throughout the project, allowing careful evaluation of the impacts of each design decision.
- Creating a bid package that segregated distinct project components into line items and bid alternatives while clearly defining options for award of some or all of the project components. This organization and bid format maximized flexibility in awarding project components to match available project funds.
When the project bids were open, the engineer’s estimate was the median of the lowest 8 bids, all of which were within 10%. Furthermore, there was only a $20,000 difference between low and second low bids, reflecting consistency in the plans and specifications.
The project was completed on time and was successfully started up in May 2012, bringing the facility into compliance with its Waste Discharge Permit.