Tag Archives: signals

UDOT Signal Engineering Team receives Governor’s Award for Excellence

Photo of team members standing with Governor Herbert.

Team members with Governor Herbert. From left to right: Shane Marshall, Mark Taylor, Carrie Jacobson, Shane Johnson, Governor Herbert, Rob Clayton, Derek Lowe, Jamie Mackey, Peter Jager and Matt Luker.

For the last three years UDOT’s traffic signal management team has been focused on bringing innovative solutions to Utahns. The team was recently recognized by receiving the Governor’s Award for Excellence from Governor Gary Herbert.

The signal management team has been working on in-house solutions to better track and time traffic signals across the state. UDOT worked with the Indiana Department of Transportation and Purdue University to create software that provides real time traffic information to UDOT. The program was then developed by UDOT and the Department of Technology Services (DTS) and is a web based Automated Traffic Signal Performance Measurement System (SPMs).

SPMs are a series of visual aids that display high-resolution traffic data from vehicle sensors and traffic signal controllers (intersection computers changing the traffic signals) that help agencies effectively manage traffic signals in ways that improve mobility, increase safety, reduce vehicle emissions, preserve pavement infrastructure and use resources more effectively. In most cases on UDOT state roadways, SPMs are accomplished utilizing the same vehicle sensors already deployed at signalized intersections for normal day-to-day operations without the necessity of having to install expensive new equipment or sensors.

The sensors allow analysis of data collected 24-hours a day, 7-days a week (not just during business hours), and provide a clear framework for performance analysis and decision-making. The transportation community uses SPMs to directly measure what they previously could only estimate and model.

The use of the real time and accurate information helps traffic signal engineers make better decisions on signal timing and traffic patterns. Bangerter Highway is a good example of how accurate information helps move traffic. The SPMs were able to increase the amount of cars that reached the intersections at a green light by 19%. The information has also helped with moving large amounts of traffic during one time or recurring special events.

All of this information helps commuters stay on the move, saving them time and money. The cost for this program and the cost of a traffic signal change is very low compared to the amount of travel savings day by day.

In an effort to help traffic around the state UDOT has shared this technology with counties and cities so that they can better understand and monitor their traffic signals. UDOT hopes that the SPM’s will help them to get a more comprehensive idea of their traffic patterns and signal accordingly.

Mark Taylor a Traffic Signal Operations Engineer said “Innovations, creativity, risk and increased transparency are necessary to meet UDOT’s needs.  Automated performance traffic measures allows us to optimize mobility, increase safety and use resources more efficiently.”

UDOT’s goal is to continually refine the use of technology in traffic signals and timing in the future. They are always looking for ways to improve their efficiency and their ultimate goal of keeping Utah moving.

This guest post was written by Adam McMillan, Traffic Operations Center Intern.

WASHTO Quality Award Winners

I am pleased to announce that the WASHTO Quality Award winners for 2013 are the Ogden Canyon Fiber Project and Traffic Signal Operations teams. It became evident as our selection committee reviewed the nominations that these two groups distinguished themselves as leaders who have made significant contributions to the Department while simultaneously improving the quality of life in our communities.

Photo of Carlos Braceras and the Ogden Canyon Fiber Project Team

UDOT Executive Director and the Ogden Canyon Fiber Project Team

The Ogden Canyon Fiber Project Team members were Jesse Glidden, Lynne Yocom, Blaine Leonard, Brent DeYoung, Rex Harris, Matthew Smith, and Dave Moss.

As many of you know, Ogden Canyon (S.R. 39) is a narrow, winding 5-mile canyon road connecting the Ogden Valley with the metropolitan area. It is a critical transportation link but a difficult location for constructing projects due to its mountainous terrain.

Our Region 1 folks initially had asked our Traffic Management Division to install a VMS sign in the canyon that would warn motorists of frequent winter canyon closures. Lynn, Blaine and Matt were more than happy to do that but while they were visiting the site they noticed construction already happening in the Canyon.

Ogden City had recently started the installation of a waterline. The team knew that underground construction of this magnitude in the canyon rarely occurred. They successfully seized upon this opportunity to partner with the city and get a fiber communications line installed along the entire canyon corridor.

This vital link to Ogden Valley now provides fiber optic communications for traffic monitoring and public communications. In addition, Ogden City enjoys a fiber connection to their water treatment plant and residents have improved cell and broadband service.

Because our team members took the time to think beyond the limited scope of their own individual duties, they were able to see the bigger picture. This synergistic approach to finding a solution will benefit thousands of people for decades to come.

I commend them for their great work.

Photo of Carlos Braceras and the Automatic Signal Performance Measures Team

UDOT Executive Director and the Automatic Signal Performance Measures Team

The first place winning team is our Traffic Signal Operations group, consisting of Mark Taylor, Jamie Mackey, Matt Luker, Shane Johnson, Derek Lowe, Peter Jager, Eric Rasband, Adam Lough and Carrie Jacobson.

Tasked with providing “World-Class” signals operations and maintenance, our folks have risen to the occasion. Adopting best practices from our partners at Indiana DOT, they have developed eight different performance measures currently available for 750 intersections. The measures provide both real-time and historical data, with all of the information housed on the UDOT Traffic website.

The program works via FTP connections located throughout the network that provide information to our traffic signal controllers. Every 15 minutes TOC servers retrieve and store “packets” of time-stamped data. This process is overseen by software engineers Shane Johnson and Derek Lowe. Anyone can access this data, which is an approach that fosters transparency and information sharing. Because of their efforts, UDOT is now the national leader in real-time traffic signal performance measures.

It’s not hard to see why in June of this year UDOT received the AASHTO Technology Implementation Group (TIG) award for their efforts in this area. But this team isn’t stopping there. By the end of the year they plan to have additional performance measures to track elements such as historical travel times for arterials and overall operations system improvements.

Both teams’ efforts have served to further our Department’s Strategic Direction.

Our Ogden Canyon Fiber Team has strengthened the economy by providing fiber optic service to Ogden City’s water treatment plant and improved cell and broadband service to residents. They have optimized mobility via a vital communications link that will facilitate traffic management and public information. They have improved safety with the capability to more effectively manage traffic, thus keeping drivers safer and getting us one step closer to our goal of Zero Fatalities.

Our Traffic Signal Operations team has strengthened the economy by improving the efficiency of the signal system. This has made a huge impact on alleviating traffic congestion and consequently the movement of goods and services throughout the state. In addition, they have implemented signal timing plans to accommodate large events such as college football games and community parades.

The signals team has optimized mobility by closely monitoring and adjusting red and green time to allow for better progression along corridors. They have improved safety by partnering with our radar vendor to track approaching vehicle speeds at intersections. To preserve our infrastructure, they have devised a way to quickly find and replace deficient vehicle detectors.

These efforts do not go unnoticed. Congratulations to both teams for their exemplary work and dedication. Please join me in thanking them for their great work as they are well-deserving of the 2013 WASHTO Quality Awards.

Information about all of the WASHTO Quality Awards nominees is available in a previous post.

Traffic Signal Performance Measures announced as a 2013 AASHTO Innovation Initiative

Engineer Mark Taylor working in an open traffic signal cabinet

Engineer Mark Taylor working in a traffic signal cabinet.

Managing traffic is an effective way to reduce congestion, save fuel costs and improve safety. One of the most visible components of the traffic management landscape is traffic signals. Day-to-day traffic challenges keep the staff at the UDOT Traffic Operations Center (TOC) very busy- especially during winter weather, special events and during the morning and evening commutes. The operators at the TOC have the ability to remotely operate nearly 80% of Utah’s traffic signals, which can be a very helpful way to alleviate traffic congestion. Each signalized intersection has a metal cabinet adjacent to the intersection that holds the equipment needed to operate the traffic signals. The equipment that operates the traffic signal can be programmed for specific traffic patterns along a corridor in an effort to better manage traffic.

Every year, the American Association of State and Highway Transportation Officials (AASHTO) identifies innovative projects that have been successfully adopted by transportation agencies across the country. One of the 2013 AASHTO Innovation Initiatives was UDOT’s Traffic Signal Automated Performance Measures program. The program developed a structure that will allow UDOT to actively manage, in real-time, its traffic signal systems which will help traffic flow as efficiently as possible along any given roadway corridor. “When we have a maximum number of vehicles arriving at a traffic signal when the light is green, traveler delay is minimized,” said Mark Taylor, UDOT’s Traffic Signal Engineer. Other benefits to well-timed traffic signals are reduction in vehicle emissions and reduction in crashes. Since traffic management needs to occur every day of the week and at all times of day, the Performance Measures program helps to monitor and improve traffic flow even when a traffic signal engineer is not available.

UDOT is moving forward with an AASHTO Technology Implementation Group (TIG) which will work to document the techniques, benefits and technologies UDOT is using for Traffic Signal Performance Measures so other interested transportation agencies can begin their own program in this important area. More information about the AASHTO Innovation Initiatives selected for 2013 can be found on their website.

Whatever the Weather

During storms, driving conditions can cause travel delay, especially during the morning and evening commute.

When a storm hits the Wasatch Front, a twenty-minute commute can turn into an hour due to slick roads, start-and-stop traffic and low visibility. What if traffic could be managed more effectively to minimize the sluggish traffic speeds drivers experience during storms?

Recent technological advances in assessing weather and controlling signals have given traffic engineers better tools to keep traffic moving in stormy weather. On some corridors along the Wasatch Front, UDOT is taking a Weather Responsive Traffic Management approach that puts the tools to use.

WRTM uses sensors, traffic signal plans designed for storm conditions, and sophisticated traffic monitoring systems already in place to move traffic more efficiently during winter weather.

Traffic on Riverdale Road PhotoDuring winter months in 2013, an urban arterial in northern Utah served as testing area for WRTM. Riverdale Road intersects a busy shopping district and connects four Utah cities with Interstates 15 and 84. Over 47 thousand vehicles travel the corridor each day.

UDOT’s results in managing Riverdale Road traffic during winter storms were very good – for motorists, that is. Drivers experienced less stopped time at intersections compared to other storm days, and overall, traffic speeds were not significantly impacted by weather.

Here’s how the WRTM system worked on Riverdale Road:

  • Traffic engineers created signal timing plans for implementation before or during a storm. The plans accommodate travel speeds that are likely during storms so that signalized intersections along the corridor work together to make traffic flow more efficient.
  • A Road Weather Information System unit was installed in the corridor. The RWIS helped meteorologists and engineers anticipate upcoming storm severity to decide which signal timing plan to employ.

    RWIS on Riverdale Road Photo

    RWIS on Riverdale Road

  • Detection units were installed overhead along the roadway. The new equipment is better at detecting traffic movement during storms, and the equipment gave UDOT traffic speeds.
  • To monitor traffic during storms, UDOT used a Signal Performance Metrics System that lets signal operators assess and adjust traffic in real-time. After a storm, the system can be used to evaluate how the signal plans worked.

Winter 2013 ended up being a challenging year to test the WRTM system. During testing, the Salt Lake City and Ogden area experienced one of the worst winter storms in the past decade. Nevertheless, post-storm review showed an average or above average improvement in performance in traffic operations in over half of the weather events, including during the major storm.

Post-storm analysis also shows that cars maintained a high level of progression from intersection to intersection with platoons of cars arriving on green lights. When platoons of cars arrive at intersections on green lights, traffic flow throughout the corridor is more efficient.

Based on the success of the Riverdale Road WRTM performance, UDOT plans to expand the system to other corridors.

Optimizing Mobility – UDOT’s Traffic Management Division

TOC Control RoomThe UDOT Traffic Management Division (TMD) houses UDOT’s Traffic Operations Center (TOC), the traffic signal management division, traveler information program and deployment and maintenance for Utah’s robust Intelligent Transportation System (ITS) network. UDOT utilizes the resources from within the TMD to plan for and react to any type of event that reduces capacity on Utah interstate and highway routes.

The UDOT TOC is operated 24 hours a day, 7 days a week, 365 days a year! TOC operators actively monitor traffic, looking for road debris, crashes or lane closures due to construction. This sophisticated ITS network includes traffic cameras, overhead message signs, vehicle detectors and much more. The fiber optic network that connects the ITS devices to the TOC provides an excellent, fast connection that allows TOC operators to react at a moment’s notice. “Our TOC operators monitor traffic throughout the state from our facility in Salt Lake City. If a crash occurs in St. George, our operators are able to use traffic cameras to locate the incident and post a message warning motorists on an overhead message sign within a matter of seconds,” said Mike Evans, Control Room Manager.

In addition to day-to-day traffic problems, the UDOT TMD also provides traffic signal support for large-scale special events. A signal management operator can remotely control nearly 80% of UDOT’s traffic signals from the TOC.

UDOT’s Traffic Management Division is charged with operating a smart transportation network. Using technology to help manage traffic is an excellent way to optimize mobility, reduce delay and increase roadway capacity. To schedule a tour of the UDOT Traffic Operations Center, please call(801) 887-3710.

2013 Strategic Direction — Part 3

This is the third part of a 4 part series about the 2013 Strategic Direction. Please also check out Part 1: Preserve Infrastructure,  Part 2: Optimize Mobility and Part 4: Strengthen the Economy.

Zero Fatalities

UDOT remains committed to safety. This new goal replaces the previous goal of “Improving Safety” emphasizing UDOT’s commitment to reducing fatalities. Some may believe that zero is unattainable, however to those who’ve lost family members on Utah roads one fatality is one too many. Zero Fatalities is the only goal acceptable to Utahns and to UDOT.

In 2012, 218 lives were lost on Utah’s roads in car crashes–the lowest Utah traffic fatalities have been since 1959. We are making progress toward our goal of Zero Fatalities, but we still have a ways to go.

Every UDOT project incorporates safety improvements. In 2012, UDOT programmed $19.2 million for specific safety projects, including:

  • 42 miles of median cable barrier installed, for a total of 231 miles since 2003
  • Approximately $17 million of Safety Program funds were assigned to specific safety projects in 2012
  • 12 new traffic signals constructed
  • 24 traffic signal upgrades constructed
  • 11 pedestrian/school crossing improvements
  • Construction of 20 safe sidewalk projects
  • Installation of 540 sidewalk access ramps

In UDOT, the focus on safety within engineering begins with planning, designing and building safe roadways. Engineering for safety is UDOT’s commitment to a safe-system approach. The main principle of a safe-system approach is the roadway is designed and built to realistically prevent traffic related deaths even when driving behaviors create crashes.

Education is also important roadway safety. Utah demonstrates its commitment to safety through outreach efforts that help educate the public and make Utah a safe place for living, traveling and doing business. These education programs include:

Since 2009, UDOT safety programs have:

  • Totalled more than 135 presentations to elementary schools
  • Reached more than 100,000 students statewide

UDOT’s Incident Management Program began in 1994 as part of UDOT’s on-going commitment to safety on Utah’s roads. From the beginning, the program has provided significant benefit by increasing first responder safety, reducing congestion and delays and reducing secondary crashes.

Snow and ice removal is a major component to safe driving in Utah. To clear snow from approximately 6,000 centerline miles of Utah’s roads, UDOT employs the latest technologies and trains crews to ensure they are ready.

  • On average, Utah receives more than 25 winter storms each year and UDOT crews remove more than 65 million tons of snow and ice from Utah’s roads.
  • To help keep our roads clear around the clock, UDOT operates a fleet of approximately 500 snowplows.
  • UDOT’s winter operations budget for the 2012-2013 winter season is $23.3 million, including equipment, salaries, sand, salt, brine and avalanche control.

2013 Strategic Direction — Part 2

This is the second part of a 4 part series about the 2013 Strategic Direction. Please also check out Part 1: Preserve Infrastructure, Part 3: Zero Fatalities and Part 4: Strengthen the Economy.

Optimize Mobility

The goal of optimizing mobility continues to include the need to build new highways, expand existing highways, build more bicycle and pedestrian paths and expand the transit network. UDOT accomplishes this by adding capacity, managing lanes, developing innovative cross roads, coordinating signals, and providing traffic information.

Since 2006, more than 575 lane miles have been added to the state system from various programs that fund more than 100 projects. Currently, capacity projects are primarily funded through the Transportation Investment Fund (TIF). Some of these projects include the I-15 CORE, Mountain View Corridor, US-40 passing lane improvements, SR-18 intersection upgrades at St. George Blvd. and US-6 passing lane improvements. These capacity projects dramatically improve delay on Utah roadways.


Without capacity improvements, delay along the Wasatch Front would have experienced a three-to-five fold increase.

UDOT currently has 124 miles of Express Lanes (62 miles both northbound and southbound) with 54 continuous miles between Spanish Fork and North Salt Lake City making Utah’s Express Lanes the longest continuous Express Lanes in the country. More than 13,000 Express Pass transponders have been purchased, speeds average 9 mph faster than the general lanes and travelers experience a higher level of safety.

Developing and constructing innovative cross roads is a fundamental in optimizing mobility on Utah roadways. Flex Lanes, Commuter Lanes, ThrU-Turn Intersections (TTI), Diverging Diamond Interchanges (DDI) and Continuous Flow Intersections (CFIs) decrease delay at intersections, reduce travel time, improve safety, and reduce the length and cost of construction.

The Traffic Operations Center (TOC) continues to be the key to providing a cost-effective and and efficient solution to help relieve congestion on Utah’s roads and highways. Using advanced technologies such as cameras and traffic/weather sensors, operators in the TOC can monitor traffic, detect problems and take actions necessary to return traffic flow to normal.

UDOT uses a variety of methods to provide actual travel times and accurate traffic and weather information to help drivers make choices that reduce delay, prevent crashes and improve air quality. By implementing an extensive Intelligent Transportation System (ITS), UDOT is able to know what is happening on Utah roads, and provide travelers the information they need to plan their routes. UDOT communicates travel information online at udot.utah.gov and through variable messages signs (VMS), traffic cameras, twitter, facebook, and YouTube, and the UDOT Traffic App.


“Warrants were issued after an investigation” is a phrase you may hear on CSI or at UDOT.

Bus going through green light in Sandy

Safety concerns, vehicular traffic volume, pedestrian traffic volume and roadway features are few things engineers evaluate carefully during the signal warranting process.

UDOT follows the criteria outlined in the Manual on Uniform Traffic Control Devices —MUTCD — that lists eight aspects of a roadway that need to be studied and individually warranted before the decision to install a traffic signal is made. Here’s the list straight from the source:

  1. Eight-Hour Vehicular Volume
  2. Four-Hour Vehicular Volume,  Peak Hour
  3. Pedestrian Volume
  4. School Crossing
  5. Coordinated Signal System
  6. Crash Experience
  7. Roadway Network
  8. Intersection Near a Grade Crossing

Traffic engineers conduct studies according to the requirements outlined in the MUTCD, crunch the data and make a decision.


It’s important to follow the MUTCD to ensure that a signal is really needed at the location. ” You want that device to get the respect of road users, ” says Mark Taylor, UDOT Signal Systems Engineer. “Otherwise, you get safety problems,” like excessive rear-end crashes, if drivers disobey the signal.

But the engineers also use good judgement when placing signals, too. “Just because it meets the requirements, we don’t need to put it there,” says Taylor.  Another approach, such as signs or flashing warning lights may provide the needed improvement.

To find out more about the warranting process, and how to request a signal in your area, see this traffic signals brochure produced by the UDOT Traffic and Safety Division.

A related post explains flashing yellow arrows: UDOT GETS FLASHY