Memphis Reg io n al In t elli gen t T r an s portatio n S y st e m
ABOVE Dynamic Message Sign (DMS) with real-time messaging: Informing motorists of an accident ahead will decrease speeds and potentially reduce the number of secondary accidents by 30 percent or more. BELOW Closed Circuit Television Cameras (CCTV) feed real-time information to operators who can easily pinpoint an incident’s precise location as well as its severity. TDOT’s website will offer up-to-date video images, a color-coded interstate map, and average speeds on specific roadway segments at any given moment.
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Tennessee Department of Transportation Shelby County, Tennessee and Crittenden County, Arkansas Engineering
The Road More Traveled
SHOWCASE TWO
Widening a Memphis-area freeway by one lane can cost an average of $3 million dollars per mile, not including land acquisition costs or construction inconveniences. Tennessee Department of Transportation officials (TDOT) recognized that improvements were necessary and turned to GS&P to develop an advanced freeway management system that would be more cost-effective, environmentally friendly, and faster to implement. The Memphis TDOT SmartWay, one of the largest ITS projects in the nation, is a great example of how significant improvements can be made without having to reach exorbitant expenses, and shows how innovative, technology-based solutions will impact the future of transportation.
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City of Memphis, Tennessee city engineer’s Award of excellence
Under a separate contract a Traffic Management Center was constructed in east Memphis, near the I-40 and I-240 interchange. State-of-the-art wireless technology connects the TMC and Memphis roadways to TDOT regional headquarters in Jackson, Tennessee, nearly 80 miles east of Memphis. ABOVE Constructing the TDOT SmartWay cost approximately one-sixth the price of adding a new lane to the region’s freeways. No additional property was acquired, and motorist delays were minimal.
TEAM
Marshall Elizer, P.E.
PIC
Rodney Chester, P.E. / Stephen Mosher, P.E.
PM
Mark Washing, P.E. / Mike Holt, P.E. / Greg Dotson, P.E.
INT E R V I E W /
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R od n e y C h e st e r , Gr e g D otso n , S t e v e M os h e r
Describe the roadway situation in Memphis that prompted TDOT to contract with GS&P.
What makes this wireless system so impressive?
Region IV is unique in the sense that it is a wireless communication system from Memphis to Jackson and uses six hub sites. Any data from any camera or dynamic message sign is transmitted over this wireless backbone to the Region IV headquarters. There’s no delay at all between Memphis and Jackson, which are 80 miles apart. It’s as if you’re sitting in the TMC controlling the cameras. Greg:
There was a lot of traffic congestion in the Memphis area, and they didn’t have any way to actively monitor or manage it or respond to incidents. Both Knoxville and Nashville had developed ITS, and they wanted to address the situation in Memphis the same way. Rodney:
Why was GS&P selected for this project? Rodney: I think, by far, the biggest reason was the great work we’d done on a similar Nashville project. We had already been working with them on these types of projects for several years and had given great service and had great outcomes.
Can you give a broad view of what the project entailed?
That’s really the biggest key. Most ITS systems that utilize wireless are more short distance, especially for the type of application that we are using. The fact that the wireless system is transmitting 80 miles away, that it is a completely redundant system, and that it can be completely run from the other location is unique. Rodney:
What are some of the features of the HAR?
You’re right. Not many people think about the environmental improvements that can come from highway construction projects, but the biggest gain is from reduced emissions. The largest amount of emissions from cars and trucks is produced when idling, not when moving, so by just keeping traffic flowing we’re helping to reduce the negative effects on air quality. Systems like this are designed to keep traffic moving, whether it’s alerting drivers to find alternative routes when there’s heavy volume or providing information to avoid accidents. Additionally, if the system can help commuters get to their destinations sooner, that’s less time vehicles are producing exhaust. Rodney:
Greg: Along the interstates, these transmitters broadcast on radio station 1660 am, and they alert motorists of any issues. When the beacons on those signs are flashing, they direct motorists to tune in for additional traveler information. Also, unique to this system is a Region IV wireless backbone system, which is primarily used by other state departments like Tennessee Bureau of Investigation and the Tennessee Department of Safety, but it also aids the SmartWay system by letting personnel at the Region IV headquarters in Jackson, Tennessee, view and control CCTVs and dynamic message signs here in the Memphis area.
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The project description boasts being environmentally friendly, but many people might not equate an interstate with environmental improvements. How do you see this system having an impact?
SHOWCASE TWO
Greg: This was one of the largest single-contract Intelligent Transportation Systems (ITS) projects ever constructed in the United States. It features closed-circuit television cameras (CCTV), speed and volume detectors (mostly radar with some video), Highway Advisory Radio (HAR), and Dynamic Message Signs (DMS) that broadcast real-time information to motorists from a new, state-of-the-art Traffic Management Center (TMC).
one of the largest ITS projects ever constructed in the U.S.
A recent study of a similar system in the Atlanta area showed a reduction in hydrocarbon emissions by 186 tons and nitrous oxide (NOX) emissions by 261 tons for a one year period. So we know that it has substantial results. This is one of the largest single-contract ITS projects ever constructed in the U.S. What unique challenges came with doing it all at once instead of in phases?
There were two big challenges. One was that the project included other states. The system goes over into Arkansas so it required a lot of coordination with Arkansas’s DOT. The other big factor was that the length of construction was so long you didn’t want to just wait until the very end to start pulling things together at the TMC and suddenly realize you had a lot of issues that had to get worked out. When you’re working on smaller projects, it’s typically not very long before you start having certain elements of it already complete. Rodney:
Typically, our ITS jobs are not so large that we have to split it up between multiple offices. This project required a lot of cooperation and was unique because our client was so familiar with us and trusted us to make the basic design decisions to keep things on track. We made all the decisions, moving it forward and keeping our client notified rather than having to have a lot of ongoing involvement with the client. Rodney:
Also, just looking at it from the construction side, we designed and built a system along the entire interstate system where we inevitably had to impose on other construction projects. Being able to make decisions also played a big role in the field as well. Since we were engaged in several other projects, we had a lot of coordination that had to happen there. For instance, we had to move CCTV poles and reroute conduit. Because of our expertise with other projects, we were able to coordinate pretty quickly and reflect on the asbuilt plans. This had to happen in Arkansas and Tennessee, so coordination between AHTD (Arkansas Highway and Transportation Department) and TDOT was key. Greg:
What part of this project really stands out to you?
How did you organize the project so that you stayed on time and on budget?
Steve: We experienced some turnover during the construction management phase and throughout the project, but we were able to effectively manage it and fill the holes without a seam. When the former construction manager left the firm, Greg Dotson slid right into that role in addition to the role he was already filling. It was a seamless transition for the most part even though we also had several senior inspectors come in and out of the project. That was definitely one area in which we excelled and avoided some pitfalls, which really set us apart.
It definitely took a lot of communication and coordination. We had teams in Memphis, Nashville, and Atlanta all working on this job. The key was making sure that we had constant communication back and forth between all three teams. Even though we had teams working on different segments, we had to make sure it was all being designed in such a way that when it came back together it all looked like one set of plans. We had a lot of coordination meetings in Memphis, and we had weekly communication progress calls between the team members. Because we have done so much other ITS work in addition to Nashville and Atlanta, we had a lot of very experienced design personnel working on the job, which also made a huge difference.
Rodney: I agree. From the design side, I’m really proud of the fact that we had one of the largest ITS projects in the U.S. with people working in multiple offices, and yet we were still able to complete the project on schedule and under budget. And throughout construction we had almost no design problems pop up, so the quality of the deliverables was extremely high. When we turned in the deliverables, the client was thrilled. And now that the construction is over, they are continuing to sing our praises. For a job that large not to have any serious hiccups with regard to the plans, schedule, budget, or the client is an overwhelmingly successful project. I think you’d have a hard time hearing any negative comments from anyone including our team and the client.
Added to the complexity was the fact that the TMC — being constructed under a completely separate contract — got delayed. When our contractor had a lot of the field elements ready for testing, the TMC hadn’t even broken ground yet. We ended up having to do a lot of testing out in the field that typically would’ve been done back at the TMC.
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SHOWCASE TWO
the key was making sure we had constant communication between all three teams
What aspects of this project set it apart from other ITS jobs by GS&P?
Rodney:
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CCTV CCTV (Early Deployment Phase)
Another interesting aspect of this project is that it indirectly led to our current long-term nine-year ITS contract with the Mississippi DOT. At the very start of the Memphis project, Mississippi’s ITS guys came to a stakeholder meeting in Memphis, which was the first time we had met Rodney:
DMS (Early Deployment Phase) VDS
them. Through the Memphis project, we started interacting with them and developed a relationship so that when the big Mississippi project was announced, we had already begun establishing a relationship we might not of had, had it not been for the Memphis ITS. The lesson there is to remember that anytime you are working on a project, you are not only continually marketing to your existing client but also with any other stakeholders that may be involved. ■
Rodney Chester, P.E., has over 10 years of ITS experience including ITS planning, design, specifications, TMC coordination, and overall program management. Greg Dotson, P.E., has experience with both ITS design and construction, and is currently responsible for managing the contractor’s maintenance requirements for the project. StePHEN Mosher, P.E., has wide-ranging experience including both project management and project professional roles on ITS, traffic, signal, roadway, draining, NEPA, and planning projects.
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Greg: I think it’s also significant that in spite of the 18-month delay with the TMC, the whole project only ended up taking six months longer. And, through all of that, we never had to go in and ask TDOT for extra money. We had a ceiling that we did not have to breach due to the efficiency and knowledge of the team so that we didn’t need a whole lot of extra help from different personnel. I think that speaks a lot to our experience and expertise. It also says a lot about our training. Heck, I couldn’t spell ITS when I first got here, and now here I am essentially running the construction and maintenance of the system!
DMS
SHOWCASE TWO
Elements associated with the TDOT SmartWay project include: • 42 Dynamic Message Signs (DMS) • 115 CCTV Cameras • 354 traffic flow sensors • Full-coverage HAR system with 16 transmitters and 42 HAR signs