Grounds for success
Gasper A. Chifici, P.E., Vice President and Division Manager, and Mark Sullivan, P.E., Program Manager, PBS&J, Encinitas, California; Paul Bushee, General Manager, Leucadia Wastewater District, Carlsbad, California
A project to install over a mile of sewer main is bound to have challenges. But when the construction site runs through one of California's most prestigious golf courses, every aspect of construction management needs to be on par.
After the City of Carlsbad, California, 35 miles north of San Diego, approved a residential development of 500 homes plus multi-family apartments, the City's Leucadia Wastewater District determined that a nearby gravity sewer main required replacement and supplementation.
The sewer main runs within the famous greens of the La Costa Resort and Spa, one of Carlsbad's most prominent businesses and the District's largest sewer and recycled water customer. Yet the sewer expansion provided no benefit for the resort. In fact, the potential for cancelled golf tournaments and dissatisfied guests and club members offered no incentive for a cooperative effort.
In spite of what could have been a challenging course, the District, La Costa and the design and construction team worked together to complete the $2.2 million sewer upgrade with minimal impacts to the resort. The key drives in this successful project were contractor prequalification and meticulous construction management.
A new sewer main would essentially parallel the existing line that would soon become inadequate with proposed development. The District's engineering design consultant considered existing sewer lines and appurtenances within the golf course and designed the least intrusive means of installing the required 5,700 linear feet of replacement sewer main, ranging from 8-inch to 16-inch diameter.
The District secured La Costa's cooperation and agreed to the resort's requirements:
|The local wastewater district's need to upgrade the area's sewer capacity required part of the golf course to become a construction site for two months.|
To compensate for lost revenue from any schedule overruns, the District would have to pay a negotiated $8,000 for every day the project extended beyond the originally-prescribed 60 days. This amount, as well as an $8,000 per day incentive for early completion, was stipulated in the general contractor's contract.
The District's design consultant assured the District that the improvements could be constructed within budget and within the narrow time window. At the 90-percent design stage, a constructibility review was provided by the Encinitas office of PBS&J. This step shortened the project schedule in two ways. First, construction could begin sooner with the review completed before final plans and specifications were available. Second, by using PBS&J's Quality Control and Assurance for Projects (QCAP) Manual, potential construction site constraints plus errors, omissions and conflicts in the construction documents could be identified early to both minimize change orders and reduce delays during construction.
An innovative prequalification step provided a defensible means of protecting the District from having to select a low bidder who, while properly licensed and bonded, may lack the technical competence to perform the work. With the District's approval, PBS&J customized the California State Department of Industrial Relations (DIR) Prequalification of Contractors for Public Projects procedures for the sewer project.
The project's prequalification requirement was advertised prior to completion of design documents so that prequalified contractors could be identified in time for the distribution of final plans and specifications. Interested contractors were required to submit financial and technical information in a set format and to answer questions related to their firm. PBS&J also conducted phone interviews with two or more previous clients of each contractor, posing 13 specific questions about each contractor's recent performance.
The contractor-furnished information was verified and rated using objective DIR guidelines. Prequalified firms were sent bid packages and invited to submit bids in accordance with public bid law requirements. Vadnais Corporation of San Diego submitted the lowest responsible bid and was awarded the contract. With Vadnais' prequalification and excellent reputation, the District was confident of the contractor's ability to produce a quality project.
|Construction was limited to a 50-foot corridor separated from the golf course by temporary fencing. During the 62-day construction period, play continued at the golf course to the fullest extent possible.|
Trusted Team Members
PBS&J, having successfully worked with the District on other construction projects, was given authority by the District to act in its best interest, even to make limited financial commitments as needed. This decision further expedited the project by speeding decision making and giving the contractor an onsite contact who could respond quickly to differing site conditions and other issues.
Only one full-time, onsite Construction Manager/Inspector (CM) was required due to the thorough constructibility review performed earlier. Richard Stinson, a highly experienced PBS&J construction manager, was selected to manage the work. All correspondence was channeled through the CM to facilitate proper documentation, ensure timely responses and minimize potential friction between parties arising from the pressure of the time-sensitive project. In addition to traditional construction management duties, such as submittal review and contract administration, the CM led weekly scheduling meetings as well as intermediate meetings called to quickly address and resolve potential problems.
The CM implemented an informal partnering agreement among all stakeholders: the District, La Costa Resort, the District's design consultant and the contractor. Each stakeholder's goals and interests were firmly understood by the other parties fostering a cooperative atmosphere. As issues arose, specific tasks and time limits were given to individuals, who consistently met the requirements.
La Costa staff knew when and where the contractor would be working each day so golf course use could be accurately scheduled. The contractor's repair crew and La Costa's grounds crew worked closely to keep irrigation operable at all times, a task that sometimes proved challenging when system components could not be easily located. To accommodate tournaments that would have impacted work, two additional days were approved in the schedule.
Replacement sewer main installed-5,700 linear feet-ranged in size from 8-inch to 16-inch.
A Hole in One
Field conditions threatened to extend the construction schedule. The soil's high water content, over 20% in most areas, required special trenching and shoring techniques. Special attention was also required to achieve the design slope of the new gravity sewer line—typically less than 1%.
Yet, the La Costa Greens Trunk Sewer Project was completed within the 62-day timeframe with no claims, accidents or required mitigations. The team even met La Costa's three-day maximum driving range closure requirement by installing a trunk sewer and restoring the range's turf within the prescribed time period. A net 5.3 percent credit brought the final construction budget down from its original projection of over $2.35 million to $2,226,281.50 with the primary savings coming from modifications lowering use of import fill, sod and other materials.
The La Costa Greens Trunk Sewer Project was awarded the California Water Environment Association's 2003 Engineering Achievement Award. Most importantly, the successful completion of the project earned praise from La Costa Resort and Spa's staff who reported no negative impacts to their operations.
Gasper A. Chifici can be reached at (760) 753-1120 ext. 2921 or at firstname.lastname@example.org; Mark Sullivan can be reached at (760) 753-1120 ext. 4511 or at email@example.com; and Paul Bushee can be reached at (760) 753-0155 ext. 3012 or at firstname.lastname@example.org.