ITS on a Rocky Mountain High

The Colorado Department of Transportation (CDOT) contends with some of the highest altitude roads in the U.S., a few reaching a staggering elevation of nearly 11,000 ft. With rapidly changing weather conditions at these elevations, roadways can become impassable within minutes.

The CDOT's road information to the traveling public not only helps manage traffic but it also saves lives.

To provide accurate, quality roadway information, the CDOT is well under way in reaching its goal of implementing the country's first statewide communication network. A fiber-optic system covering Colorado will allow the sharing of data and video throughout the state.

Currently, the CDOT is creating a telecommunications infrastructure that will be the backbone for all agencies to share information, including critical traffic data.

"The statewide deployment of CDOT's intelligent transportation system (ITS) is different than that of any other transportation department in the country," Robert Wycoff, network manager for CDOT's ITS division, explained to TM+E. "It's different in that the plan is for a statewide system and that CDOT has involved many different agencies in the process."

The CDOT's transportation management system is in its second year of a five-year strategic plan. The plan calls for the fiber-optic system to blanket the state from border to border, beginning with the two main interstates. The fiber-optic system on I-70, the main east-west corridor from Kansas to Utah, is complete. The state is installing the fiber-optic system along I-25, the main north-south corridor from New Mexico to Wyoming.

The strategic plan continues to include more highways such as the C470, the major corridor circling the Denver metropolitan area. The state has installed fiber optic on portions of this roadway with plans for completion this year.

Centralized approach

The CDOT's plan calls for a three-tiered communications network that is the backbone of the system. The intent of the statewide approach is to provide a standard for communications for ITS to meet the growing demand for a statewide system. By providing this standard, the state can design both new and existing ITS deployments to tie into the statewide communication network.

CDOT is developing the system in stages, with each stage being operational before building the next. This makes the system easy to expand by building upon what CDOT has already installed.

The first-tier network is the backbone of the system which uses SONET TDM equipment operating at data rates of OC-12 to OC-48. Connected to this is the second-tier network using SONET multiplexers to provide data links for video surveillance out in the field. The ITS devices tied into this level include cameras, highway advisory radio (HAR), both AM and FM, and variable message signs (VMS).

The third tier could be one of four systems, depending on the type of application CDOT is using in the field. The type of application in the field depends on the topography, according to Wycoff. It also depends on where CDOT is in terms of implementing the statewide fiber-optic network.

Generally, tier three consists of multiple applications, depending on the topography in the region. Everything from mountains to deserts make up the state's varied landscape. If the state were flat with major cities along its landscape, running the fiber-optic system would be straightforward. Instead, CDOT "juggles" the third tier to accommodate whatever the region and the state's ITS budget allows.

For the majority of applications, the third tier uses Cornet Technology Inc.'s (CTI) CODECs to bring the video back to the nearest traffic management center (TMC). The CTI devices convert the analog video to digital format, encode it using the MPEG-1 or MPEG-2 algorithm and place it on fiber connecting CDOT's TMCs. This allows the operators in the TMCs to view road conditions, modify messages and implement other traffic management techniques in real-time.

The encoded videos from the CODECs can be brought back to the TMC either on T1 using public telephone network or by 10/100 BaseT Ethernet using TCP/IP.

"CTI provides an excellent platform to bring video from our cameras in the field back to the traffic operations center," said Wycoff. "Once we receive the video in our center, we make it available to the traveling public."

The general public can see the video over local television stations or a cable channel. Additionally, the CDOT posts the captured images on their website (www.cotrip.org).

The traveling public either can access the information by listening to the radio station or can call for information. Future technology will make it even easier for motorists to receive the latest roadway information in their vehicles.

"We prefer to work with companies that will go the extra mile for customers and CTI did whatever it took to meet our needs," said Wycoff. "The CTI people know ITS and incorporated the CDOT's needs into their products, in a short time frame, and kept costs reasonable."

Technological revolution

Technology changes rapidly in ITS, and keeping the products offered to the industry on par with technology is an ongoing challenge.

For example, Wycoff explained, the cameras CDOT uses in the field provide its viewing direction.

"We would not be able to take advantage of the new features the cameras provide without CTI people keeping their products current with the technological changes," Wycoff said.

Having advanced hardware in the products makes it easy to change the firmware to meet our customers' requirements, explained Sant Gupta, CTI's vice president of sales, who works with CDOT.

Filling in the gaps

"We do have very rural areas that are just not feasible to run fiber optic to so we will use the products to encode the video and transport the images back to our TOC," explained Wycoff.

Major construction projects need traffic management devices and the state uses the CTI CODEC to relay vehicle information back to the traffic management center. One such project is a major highway-widening project in the heart of Denver through the technology center. This $1.67 billion project known as TREX uses many ITS devices to help traffic run smoothly during the construction project.

When the 13 miles of highway widening of I-25 is complete in 2007, a major benefit is that the ITS infrastructure is part of the project scope. There will be 59 cameras, variable message signs, highway advisory radio, all built on a fiber-optic infrastructure. "ITS will be part of the day-to-day operation of the roadway," explained Wycoff.

TOC's new home

Along with a five-year plan to implement fiber optic statewide, CDOT is remodeling an existing building to house its new TOC. Using a portion of the building's space, CDOT will have a state-of-the-art operations center to include the latest in technology. The remodeling will be complete in July 2003 with move in set for August.

CDOT will have three TOCs linked together with full fiber redundancy meaning that if something happened to any of the locations, the other TOCs can back it up. All the information going to the traveling public is from the Denver office.

Currently, two TOCs exist: one in Denver and one on the west slope. The third TOC is in the building stages in Colorado Springs and is the result of a partnership effort between the city and CDOT.

Partnership approach

A key in reaching the goal of implementing this statewide system is CDOT's success in forming public private partnerships, making the project a truly cooperative effort among Colorado agencies.

CTI's Gupta praised the CDOT for its ability to involve many agencies in the statewide plan from the beginning. "CDOT has a highly experienced and knowledgeable team and has been instrumental in getting full cooperation from the right stakeholders in the statewide system."

"We have been successful in forming partnerships with cities, counties and community colleges in our state on the implementation of our system," Wycoff explained. The state also has formed partnerships with a number of private companies, all helping the state to reach its goals.

Two of the private partners with the state are television organizations and local cable programming. Television stations use the video images CDOT cameras collect and show traffic situations on Colorado roadways. "This helps get the information to the public," Wycoff added.

Skiers at Vail can see the road conditions on the main roadway connecting Denver to the high country, thanks to a partnership agreement between CDOT, the city of Vail, and a local video production company, Alpine Vista Productions.

Viewers can see video images collected from CDOT's 11 cameras on I-70, the main road connecting Denver to the Rocky Mountains. The CTI CODEC relays the video back to Denver's TOC.  Viewers of the public access channel in Vail and Eagle County can see the video over Channel 19. Adding a live weather feed provides viewers even more up to-date information, explained Mike Orlowski, owner of Alpine Vista Productions.

"Seeing is believing," said Orlowski. "When people see white-out conditions on the roadways, they are more likely to believe it. Maybe these people stay overnight in Vail instead of traveling or they wait for a while before getting on the road to travel home. Whatever the case, this information is critical for people to see before they start their trip."

"It's a winning situation for everyone involved," said Wycoff. "The benefit for CDOT is awesome since people can see what we are doing."              

The future

"Deployment of the statewide system is growing and blossoming in ways we never dreamed of earlier," commented Wycoff. When Colorado completes its standardized center, this concept could easily extend beyond Colorado state lines. A good example of this Wycoff gives is the Amber Alert. "For an Amber Alert, Colorado would need to alert the bordering states," he explained.

The future looks bright. With new technology in ITS emerging about every 18 months, Wycoff's challenge is to keep current with what's new.                          TME