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Virginia's new diverging diamond interchange.

It may not seem like it, but with more than 58,000 miles of road and 21,000 bridges, the state of Virginia has the third largest state-maintained highway system in the country. From the Blue Ridge Mountains in the west, to the Chesapeake Bay in the east, this vast highway infrastructure system travels over a complex array of terrain that has been known to make road building a challenge in the Commonwealth. During the last 10 years, design-build contracting is one of the tools that the Virginia Department of Transportation (VDOT) has increasingly used to help expedite the transportation projects that keep Virginians moving.

The design-build concept, relatively new to the transportation industry, has been used in vertical construction for centuries. Essentially, an owner contracts with one entity to provide a turn-key product within a set deadline and budget. For highway projects, the design-build team takes the project from conceptual plans through final design, right-of-way acquisition, utility relocation, and ultimately construction. By placing the engineering consultant and the construction contractor on the same team early on in the project life cycle, the engineer is able to cater the design to the contractor’s means and methods. Likewise, the contractor is able to consult with the engineer during construction without threatening liability if field conditions aren’t always as they appear on the plans.

VDOT has completed more than 35 design-build projects since 2007 and has another 20 design-build projects currently underway. All told, these projects represent more than $1.8 billion of Virginia’s most critical transportation investments in the last 10 years. This significant effort has not gone unnoticed, as the Design-Build Institute of America (DBIA) recently named VDOT as the 2016 Owner Agency of the Year.

Leading this effort is Shailendra Patel, director of VDOT’s Alternative Project Delivery Division. Patel has helped lead VDOT’s designbuild program since its infancy and has a unique viewpoint on where it’s been and the direction it’s headed.

“In Virginia,” Patel said, “the use of design-build contracting has significantly increased over the last several years. The use of designbuild contracts varies from low risk projects to the most complex transportation projects. In fact, design-build has become the preferred project delivery method for many of Virginia’s most complicated transportation projects. The success of this program would not have been possible without the support of Virginia’s private-sector construction industry. They have fully embraced the challenges and triumphs associated with design-build contracting.”

Raising the bar

According to March 2016 data provided by DBIA, design-build contracting is permitted in 41 states across the country, but only eight states, including Virginia, allow for a contractor’s qualifications to be considered as part of the bidding process (https://www.dbia.org/ advocacy/state/Documents/design_build_maps.pdf). Virginia utilizes a two-phase qualifications-based selection process on its most complex design-build projects, such as widening I-66 near Washington, D.C., to assure the traveling public that only highly qualified teams are competing to build these high-priority transportation projects.

In the first phase of the procurement process, interested contractors submit Statements of Qualifications (SOQs) to describe the qualities that separate their team from the competition and make them uniquely qualified to design and construct the project. A VDOT Selection Committee will then review each submitted SOQ and determine the three highest-ranked teams that will be invited to submit proposals for the project.

This selection is based on:

  • each team’s previous experience designing and constructing similar projects;

  • qualifications of key personnel who will be instrumental in the delivery of the project if chosen; and

  • major risks associated with the project and the associated mitigation measures the team will take to ensure the project’s success.

Free-flowing left ramps on Virginia’s new diverging diamond interchange reduce congestion and improve safety.
Photo: VDOT

The three highest-ranked teams submit Technical Proposals and Price Proposals to be considered. Technical Proposals are scored in a similar fashion based on a team’s proposed design concept and intended means and methods for the construction of the project. The technical score is weighted 30 percent and combined with a score for the Price Proposal, which is weighted 70 percent. The result is the selection of a team that provides the best overall value for the project.

Once the contract is awarded and VDOT issues a Notice To Proceed to the selected team, the design-builder has a specific duration, generally 120 days, to identify differing site conditions and demonstrate the impact each differing site condition has on the project’s proposed schedule and budget. After the specified duration, known as the Scope Validation Period, has expired, the design-builder can no longer submit requests for additional time or money associated for differing site conditions. This contract clause is utilized by Virginia to transfer the risk associated with changed conditions to the designbuilder and its use has been widely successful in reducing the amount of work orders issued on large-scale, complex projects.

Another unique aspect of VDOT’s design-build program is the assignment of quality assurance responsibilities to the contractor. On typical highway construction projects, the owner performs dayto- day materials testing and inspection activities to verify that the construction conforms to the plans and all contract specifications. VDOT reverses this trend and requires the design-builder to hire an independent professional engineer to serve as the Quality Assurance Manager (QAM). The QAM establishes and maintains the project’s quality assurance program with general oversight provided by VDOT. The contractual relationship between the design-builder and the QAM allows the design-builder to be in control of the materials testing and inspection schedule. This greatly reduces the likelihood of an owner-caused delay because an inspector is not available, while still allowing VDOT to maintain final authority for the construction of the project.

Design and construction were completed in just 15 months for the new diamond interchange on I-295 at Meadowville Technology Parkway in Richmond, Va.
Photo: Curtis Contracting

Sparking economic development and fostering innovation

Design-build contracting accelerates project schedules by allowing contractors to concurrently perform many activities that are performed sequentially on traditional highway construction projects. For example, the design-builder can begin construction on initial phases of the project that have already been approved, such as erosion and sediment controls or drainage structures, while the final roadway design is finalized.

Additionally, the design-builder has the ability to construct around complicated right-of-way parcels and stubborn utilities until they can be acquired and relocated. The efficiencies associated with design-build contracting can shave months off of the project schedule for simple projects and can expedite complex projects by as much as several years. This time savings has resulted in significant economic development benefits on recent VDOT projects.

On I-295, the beltway around Richmond, Va., a new interchange at Meadowville Technology Parkway was designed and constructed by Curtis Contracting in just 15 months. Construction of the interchange was instrumental in Amazon.com deciding to break ground on a 1 million-square-foot distribution facility that brought more than 1,000 new jobs to the region (www.richmond.com/business/article_ b6a14b74-0e7a-5fd5-8f73-92de170bb029.html). Although the Meadowville Interchange was Curtis Contracting’s first experience as a design-builder, they knew that it was going to be a success right from the start.

“As a company, we had decided that we weren’t going to participate in the economic recession,” said president Andy Curtis. “So we blended together a fantastic team of innovative designers with dedicated construction professionals and the results we achieved together were phenomenal. Whenever an issue arose in the field, the engineers that designed the plans laced up their boots and were right there with us solving the problem the very next day.”

Since completion of the Meadowville Interchange project, Curtis Contracting has gone on to successfully complete another three design-build projects for the state of Virginia.

The teaming experience and avenue for innovation are some of the things that convinced Corman Construction to become one of the largest design-build firms in the mid-Atlantic region. “We are constantly seeking the best designers and contractors to partner with on design-build projects,” said Corman’s Vice President of Project Development Jo Ellen Sines. “In our mind, the best team will deliver the best product for the client.”

This philosophy was put into action when the Corman Construction team was selected to construct Virginia’s first diverging diamond interchange on I-64 at Zion Crossroads. A diverging diamond interchange is unique because it physically shifts drivers onto the opposite side of the road to eliminate many of the conflict points associated with traditional diamond interchanges. Instead of stopping and waiting for opposing traffic to clear before turning left onto the interstate, traffic is already on the other side of the road and can make a free flow left. This avoids conflict with oncoming traffic and vastly reduces queues at the interchange.

View a video visualization of the I-64 at Zion Crossroads diverging diamond interchange project at https://www.youtube.com/ watch?v=kYOCC1oUivo).

The diverging diamond concept originated in France in the 1970s, but it was not until June 2009 that the Missouri Department of Transportation constructed the first diverging diamond in the U.S. The design has proven increasingly more popular in recent years across the United States because it can substantially improve operations at an interchange without the high costs typically associated with interchange reconstruction. This is due in large part to the fact that the existing bridge carrying the cross street over the interstate can be salvaged without widening the superstructure.

Innovation, economic development, expedited schedules, and enhanced partnering are four of the main reasons that VDOT will keep turning to design-build contracting to deliver its most critical transportation projects.

IAN MILLIKAN, P.E., PMP, is the Design-Build Program manager for VDOT’s Construction Division. He was named one of Civil + Structural Engineer magazine’s Rising Stars for 2016. For additional information about Virginia’s program, contact Shailendra Patel at shailendra.patel@vdot.virginia.gov or Ian Millikan at ian.millikan@vdot.virginia.gov.