Principles and Guidance for Presenting Active Traffic Management Information to Drivers (2021)

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132 APPENDIX A: Full Interview Responses & Follow-Up Survey Results Full Interview Responses California respondent – Marco Ruano, marco.ruano@dot.ca.gov 1. What ATM strategies are currently deployed or being considered for deployment in your jurisdiction? • Dynamic junction control – I-5/SR 110 Arroyo Seco Parkway – this is on a substandard facility that has queuing and other safety issues – deployed pavement lighting (discontinued use after 2-3 years) and overhead signs in 2010 to control access to shoulder on the connector ramp during the afternoon peak: 3-7pm, Monday-Friday. We saw improvement in congestion and safety, but have issues based on driver perceptions on what they can and cannot do. • Dynamic lane use control – under consideration – SR 110 Arroyo Seco Parkway – developed a project study report for corridor upstream of I-5 that has many curves and substandard geometry, e.g., on-ramps have stop signs with no acceleration ramp, no deceleration lanes. This proposal would make the outside lane an auxiliary lane only during off-peak times when traffic speeds are higher and less safe for slow merging or exiting traffic with overhead signs, and some pavement markings at on-/off-ramps. • Dynamic shoulder lanes, VSL, Queue Warning – different strategies under consideration – I-105: developed a ConOps, as well as Implementation and High-Level Design Plans. 2. For each ATM strategy, please specify how is ATM information disseminated to drivers, i.e., overhead signs (one sign for each lane), overhead signs (one sign for multiple lanes), lateral roadside signs, in-vehicle displays, smartphone applications, other. In-pavement lighting and overhead and roadside signs for I-5/SR 110, not full gantries Photos, presentation: https://www.nhi.fhwa.dot.gov/resources/docs/active_traffic_mgmt.pdf 3. For each ATM strategy, what kind of signage is used? i.e., fully dynamic sign, static sign with dynamic elements, other. Fully dynamic, not full color 4. What factors were used to prioritize funding for your ATM deployments? i.e., safety benefits, mobility benefits, other. • Dynamic junction at I-5/SR 110 – deployed as part of a safety program, which looks at data driven locations and are given the higher priority • I-105 – mobility – working now to get to the project initiation phase with risks, benefits, etc. to then program the project for funding for construction, most likely from regional funding, or as part of a conversion of HOV lanes to HOT lanes, which would entail P3 funding • SR 110 Arroyo Seco Parkway – safety-driven

133 5. What resources did your agency use (e.g., documents, guidance, peer deployments) to inform the design of your ATM deployment, including signage, display format of information, content, timing, and priority for displaying information, as applicable? • Dynamic junction control at I-5/SR 110 was an in-house idea • For I-105 – we had a consultant team (Cambridge), worked with FHWA Office of Operations, and had access to other peer deployments. This project included a second major element: a framework for Caltrans to evaluate ATM strategies in various corridors, developed a tool based on deployments around the country; then use that tool to select a corridor and come up with potential alternatives for deployment. 6. How did your agency choose the types and distribution of signs (e.g., fully dynamic over every lane at ¼-mile spacing) for your deployment? Dynamic junction deployment at I-5/SR 110 was based on an idea, and did not do a systems engineering process. 7. Has your agency made any changes to the way information is presented to drivers since your ATM deployment first began operations? (e.g., different message wording, different symbols, different spacing or sign configurations, different types of signage, distance presented upstream, different thresholds in algorithms for operations, etc.) If yes, please explain. Dynamic junction at I-5/SR 110 – pavement lighting was active for 2-3 years. It was deployed to help get compliance, when the lane was closed it was lit as a solid white stripe and the overhead sign showed an X, and when the lane was open the lighting would be off (no barrier) and an arrow would be shown on the overhead sign. There was still a high violation rate, and ongoing maintenance issues with the pavement lighting that was challenging to access. As such, the pavement lighting effort had to be abandoned, but overhead signs are still working. 8. How does your agency balance the needs of drivers versus the infrastructure, operations, and maintenance costs for ATM? This is a struggle – we strive to provide as much information to drivers as possible, but there are many constraints: funding, political, environmental. Public acceptance is key to gauge the success – and will help find this balance point – how will the public react and will they understand it? Keep the public engaged through the process. Early dialogue is also needed with the highway patrol – law enforcement buy-in is key because you need compliance by the traveling public, and when you’re doing something new that drivers are not used to, you need enforcement. Dialogue with maintenance personnel is key too. 9. Has your agency evaluated the return on investment of your ATM deployments? If so, how was this done? No – we did look at crash rates and also showed some benefits for congestion. 10. If you could do the ATM deployment again, what would you do differently and why? Specifically, would you use the same method for displaying information to drivers (e.g., the types and distribution of signs: fully dynamic over every lane at ¼-mile spacing)?

134 Dynamic junction at I-5/SR 110 – A new project is underway to help manage the movement in that lane with only digital overhead signage. The intent was/is to make it more adaptive after we worked out the kinks, but had challenges with initial design. An evaluation by PATH at UC-Berkeley looked at operations and alternate strategies that might provide additional benefit using modeling. Didn’t do a systems engineering process or consult with maintenance staff, and in hindsight, that would’ve been helpful, particularly from an operations and maintenance standpoint. 11. Has your agency surveyed or received feedback from drivers, either positive or negative, about the type of information they receive or the dissemination mechanism that is used? Please explain what drivers do and do not like about the deployment. No systematic feedback; received some emails and got anecdotal feedback from California Highway Patrol. About half of DMS are used to convey travel times, and some present alternate route options on time to get to a given destination – did have a website to get feedback. Findings showed that it was less important to drivers what the exact time was, but the relative time versus their normal time – people interpret the points differently (i.e., everyone has a different context for “downtown”) 12. What types of information and dissemination mechanism do you believe is most effective for ATM? We still struggle with how to safely convey information to smartphones without it being a distraction, perhaps audio is one way? Improved roadside signage is being deployed, and the new digital overhead signs are effective. Still unsure of the effectiveness of pavement markings. 13. Has your agency given any consideration to in-vehicle or smartphone application messages for deploying ATM in a connected vehicle environment? Has your agency considered phasing out the deployment or operations of traditional ITS or on-road signing, such as DMS? If yes, please explain. Caltrans is still deploying new ITS infrastructure. It is still a challenge for Caltrans to maintain infrastructure; we still are using 50-year old loops in places and have not been able to deploy automated detection methods yet – we are working to get smarter. Nothing is being phased out, but as technology evolves, Caltrans deploys updated devices. Illinois respondent – Juan Pava, Work Zone Safety Engineer, juan.pava@Illinois.gov 1. What ATM strategies are currently deployed or being considered for deployment in your jurisdiction? Temporary systems for work zones: queue warning systems, travel time estimation, dynamic alternate routing with ITS based on congestion levels; have considered dynamic merge systems to get rid of concerns with zipper merge

135 Permanent systems: reversible lanes on I-90, I-90 Tollway SmartRoad under construction for dynamic lane control and queue warning opening 2017, signs over each lane; shoulder running for buses [NOTE: RESPONSES BELOW ONLY FOR WORK ZONE SYSTEMS] 2. For each ATM strategy, please specify how is ATM information disseminated to drivers, i.e., overhead signs (one sign for each lane), overhead signs (one sign for multiple lanes), lateral roadside signs, in-vehicle displays, smartphone applications, other. Generally, fully dynamic PCMS on the side of road are used. Have incorporated overhead DMS, and also used static signs with flashing beacons – “real-time traffic control system,” e.g., “Slower traffic ahead when flashing.” For a queue warning system, deploy as many PCMS as necessary to span the length of the queue, based on a queue analysis that is done to determine how far the queue will reach. Place dual PCMS on both the inside and outside shoulders, and develop a project-specific design for deployment. We require them to be synched, but it is very difficult to control the synchronization, so now stagger them by about 500’ so that they are not directly side by side. If they do get out of synch, it can be very confusing as drivers try to read both signs. Staggering is also helpful if a car is in the middle lane between large trucks, staggering raises the chance that they can read one of the PCMS. 3. For each ATM strategy, what kind of signage is used? i.e., fully dynamic sign, static sign with dynamic elements, other. (see above) 4. What factors were used to prioritize funding for your ATM deployments? i.e., safety benefits, mobility benefits, other. -Primary reason for queue warning systems is safety: to reduce rear-end crashes. By reducing crashes, there is a benefit to mobility also – if excessive queues (a mobility issue), that triggers the need for queue warning to avoid crashes (safety). -Have considered dynamic merge systems to reduce safety concerns with zipper merge. -For dynamic alternate routing and travel times – look at mobility benefits. -Districts have on-call contracts for deploying ITS in short-duration projects, typically less than 2 weeks, where the total cost of the project may not warrant ITS, but there is potential for unexpected queues. These are almost exclusively used for queue warning systems. 5. What resources did your agency use (e.g., documents, guidance, peer deployments) to inform the design of your ATM deployment, including signage, display format of information, content, timing, and priority for displaying information, as applicable? FHWA provides good guidance for the deployment of ITS systems: The Work Zone ITS Implementation Guide. Look at expected number of sensors and PCMS, but also determine the final layout between service provider and IDOT staff, and can make any needed changes before deployment. We rely heavily on the ITS vendors, because they’re very aware of what they are able to provide and what their systems are capable of achieving.

136 We typically use the system-provided recommendations for messages to post on the PCMS – if there is no congestion, post something like “left lane closed ahead, use caution”; when speeds drop below a certain threshold, post “slow traffic ahead”; when speeds are under 25 mph, post something like “slow traffic ahead, be prepared to stop.” 6. How did your agency choose the types and distribution of signs (e.g., fully dynamic over every lane at ¼-mile spacing) for your deployment? For a queue warning system, we deploy as many PCMS as necessary to span the length of the queue, based on a queue analysis that is done to determine how far the queue will reach. Also, a study with University of Illinois looked at the performance of ITS systems based on different sensor types and reliability of sensors. 7. Has your agency made any changes to the way information is presented to drivers since your ATM deployment first began operations? (e.g., different message wording, different symbols, different spacing or sign configurations, different types of signage, distance presented upstream, different thresholds in algorithms for operations, etc.) If yes, please explain. We have not changed much. However, IDOT still has not finalized a specification; we have a spec that we continue to tweak based on lessons learned from our experiences. We generally leave responsibility to the individual districts on the displayed message – if they hear feedback or complaints, their engineer can suggest a different type of messaging. There isn’t standard messaging. On I-74 near Champaign we tried to provide queue warning, travel time, and alternate routes on the same PCMS – had a very complicated logic for the PCMS, which led to providing confusing messages because of the large message set – how much information can you give to the drivers in a clear, concise way to give all the information necessary? We reverted back to a queue detection system primarily rather than do all 3. Doing all three can be done in the future for the same project, but we think next time we would need signs to be dedicated for each type of system. 8. How does your agency balance the needs of drivers versus the infrastructure, operations, and maintenance costs for ATM? This is a difficult question to answer for these ITS systems because the purpose of deploying these systems is for incident mitigation or mobility improvement, and it’s difficult to gauge something that isn’t happening – i.e., these systems help to prevent crashes. A need of the driver is to have reliable travel times, so we assume the cost of providing ITS is worth the theoretical benefit of deploying based on the improved mobility due to reduced crashes. 9. Has your agency evaluated the return on investment of your ATM deployments? If so, how was this done? Nothing formal – this is very difficult to do, especially with work zones because they are short-term and conditions are different for different locations, etc. Ted Newsy in District 8 did a rough calculation on the number of crashes before and after the deployment of ITS, but we have not conducted a thorough benefit-cost analysis.

137 10. If you could do the ATM deployment again, what would you do differently and why? Specifically, would you use the same method for displaying information to drivers (e.g., the types and distribution of signs: fully dynamic over every lane at ¼-mile spacing)? 11. Has your agency surveyed or received feedback from drivers, either positive or negative, about the type of information they receive or the dissemination mechanism that is used? Please explain what drivers do and do not like about the deployment. We have not conducted any formal survey or study on user satisfaction or perception. Different districts have heard feedback informally, usually negatives: complaints from drivers who were not sure of what the message meant or timeliness of the message being relayed to the PCMS, e.g., delay on sign displayed 30 minutes, but it was actually 45 minutes, or sign says there is stopped traffic ahead when there was no issue. 12. What types of information and dissemination mechanism do you believe is most effective for ATM? On-board messaging would be great, but that is far into the future. Regarding PCMS, have heard anecdotally that people may be starting to get numb to them, so there is a push from some Districts to use static signs with flashing beacons instead – drivers may be more likely to read the sign if they see flashing. ATM information goes beyond road users, it is also important for the agency to know what is going on – it is a public information tool, but also performance management infrastructure. 13. Has your agency given any consideration to in-vehicle or smartphone application messages for deploying ATM in a connected vehicle environment? Has your agency considered phasing out the deployment or operations of traditional ITS or on-road signing, such as DMS? If yes, please explain. There is a lot of talk in the industry re: DSRC and WAZE, but IDOT is not considering deployment; it is an immature technology and we don’t want to add another layer of distraction before it has been proven. We are not phasing out or slowing down deployment of traditional ITS. Minnesota respondent – Brian Kary, brian.kary@state.mn.us 1. What ATM strategies are currently deployed or being considered for deployment in your jurisdiction? Temporary • Dynamic lane reversal – now using moveable barrier for construction project on a 6-lane segment of I-94 that’s being operated as 5-lanes during construction; always keep three lanes in a peak direction; had a similar project on a 4-lane segment of I-494 being operated as three lanes. • Dynamic shoulder use – the segment opened on I-35W northbound in 2009, but is going away next year during construction to re-build the freeway with more lanes, and will not be in place afterward.