Finishing the Job in New Orleans
Industry and government are leveraging the advantages of designbuild to ensure that the last major civil infrastructure components of the $14.5 billion Greater New Orleans Hurricane and Storm Damage Risk Reduction System are delivered and in place ahead of the 2017 hurricane season.
By R.L. Mullins Jr., Ph.D., P.E., PMP, AICP, M.SAME, and John D. Take, P.E., ENV SP, M.SAME
Alongside Lake Pontchartrain in New Orleans, execution of the last elements of one of the largest civil infrastructure programs in the nation’s history, the post- Hurricane Katrina flood protection system, is now underway.
The U.S. Army Corps of Engineers (USACE), the Louisiana Coastal Protection and Restoration Agency and a designbuild team from industry have co-located to Louisiana to enhance communication and quality to deliver the $615 million Permanent Canal Closures and Pumps (PCCP) project ahead of the 2017 hurricane season and bring further critical infrastructure support to New Orleans.
In August 2005, Hurricane Katrina charged across the Gulf of Mexico leaving more than 1,800 people dead and $81 billion in property damage. In the aftermath of the storm and subsequent infrastructure failures, which left some 80 percent of the city flooded, USACE New Orleans District was tasked by Congress with bringing the existing levee system up to a 100-year level of protection.
The $14.5 billion Greater New Orleans Hurricane and Storm Damage Risk Reduction System includes 350-mi of levees and floodwalls.
The capstone of this tremendous undertaking is the PCCP project for the 17th Street, Orleans Avenue and London Avenue canals in Jefferson and Orleans Parishes.
The purpose of the new closure structures is two-fold: to provide a surge barrier against storms rolling across Lake Pontchartrain and to pump outfall canal drainage flows back into the lake during non-tropical storm events.
The structures must be built to protect against the current 100-year storm (categorized as having a 1 percent chance of occurring in any given year). They need to be adaptable for possible future conditions and be self-sustainable for operators for up to five days off the grid. Moreover, the combined pumping capacity of the three stations is designed to be 24,200-ft³/sec, which could fill New Orleans’ 76,468-seat Superdome in less than 90 minutes.
Other notable project challenges include the soft Southeast Louisiana soils, system ventilation under 200-mph wind loads, maintaining front line hurricane protection during hurricane seasons, and reducing the risk of impacts on adjacent residential areas. In addition, the new PCCP facilities must work in close coordination with the existing Interim Closure Structures and upstream Drainage Pumping Stations to maintain outfall canal water levels and to reduce the risk of hurricane storm surges during construction and until the interim structures are removed.
In April 2013, USACE New Orleans District awarded a $615 million designbuild contract to PCCP Constructors, a Joint Venture (PCCP JV), with Stantec Consulting Services Inc., as designer of record. Since the start, the team’s overarching challenge has been to minimize the project delivery schedule while still meeting contract requirements. Its core strategy was to develop a single solution that could be fielded, with minor adjustments, to all three project sites.
Most architectural, hydraulic, mechanical, electrical and structural design elements have proven to be readily standardized. Temporary works, geotechnical and civil design elements, such as site access and underground utilities, were the focus of adaptive design efforts reflecting the unique attributes of each individual project site and its surrounding neighborhood. Visual, textural and material selection architectural cues, for example, were taken from the early 20th century Drainage Pumping Stations that are still being operated by the Sewerage and Water Board of New Orleans.
A second clear strategic focus was the pump itself. The team designed from the pump outward, establishing a progressive tier of major design decisions. Standardizing on large pump sizes that would be deployed to each site during the proposal phase accomplished this goal and also served both to minimize building footprints and simplify operation and maintenance issues. The same approach was taken when sizing the generators and other key pieces of equipment. After these strategic decisions were made, the building envelopes and site designs followed.
In order to validate the bypass gate, pump station intake, siphon discharge and other aspects of the functional design such as compliance with Hydraulic Institute standards, the team developed a comprehensive flow performance testing and validation program. This program included:
- 1:4.679 scale physical models of the 900-ft³/sec pumps;
- 1:6.617 scale physical models of the 1,800-ft³/sec pumps;
- 1:16 scale physical models of each pumping station intake forebay for both current and possible future conditions; and
- 1:10 scale physical models of the pumping station siphon discharges.
The physical models were further supplemented with a cross-calibrated variety of 1D, 2D and 3D computer models of the same project domains to provide further insight into both equipment performance and outfall canal conditions. The proposed design’s ability to function in relation to 16 specific hydraulic project performance criteria was confirmed in this manner. Government witness testing for the physical models and factory testing also occurred. as part of the program.
The project delivery team validated Gen. George Patton’s adage that a good plan now is better than a perfect plan later. Its proposal included a fleshed-out conceptual design of, and schedule for, the overall project. The proposal provided a sound planning basis for project execution and continues to be the single source of truth for the design against which all subsequent decisions are measured and validated. Three C’s—cooperation, collaboration and communication—were identified as key ingredients for success.
PCCP JV developed an aggressive schedule that is set to deliver the project ahead of the contract requirement of 1,336 days. In order to achieve this success, chances for miscommunication or misunderstanding needed to be eliminated or greatly reduced. A critical decision early on was to use a collaborative approach to project design delivery. PCCP JV wanted all key parties co-located to enhance collaboration and reduce issue resolution time. A representative selection of PCCP JV, Stantec, key USACE New Orleans District representatives, members of the district’s customer’s staff from the Louisiana Coastal Restoration and Protection Agency and members of the district’s Design Quality Assurance Team from URS Corp., located together in Metairie, La.
This approach has enhanced communication, reduced the time needed to reach decisions, and broke down a number of organizational barriers that could have constrained project execution. For starters, regular over-the-shoulder working sessions and decision logs could be easily coordinated and updated to discuss and document work package components and design packages. This over-the-shoulder approach has allowed the team to take advantage of the flexibility available in the contract for accelerated review processes.
Secondly, decision-makers have been able to walk down the hall and resolve potential issues rather than “throwing them over-the-wall” through e-mail or similar methods. This has reduced the chance of misunderstanding and encouraged frank communications among the project delivery team. Relocating key team members avoided the need to relocate the entire design and drafting production roster, yet still enabled for continuous daily parallel processing of both design coordination and production efforts. Online design team communication tools (such as ProjectWise, SharePoint, WebEx and Lync) have proven critical in connecting the geographically separate design coordination and production team members.
An additional communication feature was the use of six discipline-based task teams (Civil, Geotechnical, Hydraulics & Mechanical, Electrical, Structural & Architectural, and Temporary Works). These groups contained project design coordination and production representatives of all the organizations involved. They met at least weekly, if not more often, to discuss issues or concerns in their teams and review products in the over-the-shoulder approach. As the early single-discipline study and design packages gave way to multi-discipline packages, elements of the various task teams set up periodic joint cross-discipline meetings to facilitate communication and integration.
As a design-build project, various elements were prepared simultaneously then blended into fast-tracked packages. This enabled completion of early design management, procurement and construction packages, which accelerated project execution (quality control and configuration management plans) and construction while other elements were being prepared.
USACE and the joint venture team also have put in place an extensive public involvement campaign to keep the community informed of project progress.
The delivery method chosen for the PCCP project has proven effective through the first 250 days of execution. As of December 2013, 115 of 117 scheduled design packages had been completed with approximately 150 more to come. Temporary works (such as cofferdams and temporary flood protection) and various site/civil packages are already being constructed.
Thanks to a collaborative approach that has made it possible for the team to develop, review and deliver high quality packages for construction on an accelerated timeline, the PCCP project is on schedule for completion ahead of the 2017 hurricane season.