August 18th, 2014

400 South Corridor Assessment

No Comments, Optimize Mobility, by Guest Post.
LRT Study

Figure 1. Roadway and LRT Study Network

This study evaluated current and future traffic and transit performance along the light rail transit (LRT) corridors within the University of Utah area, 400 South and Downtown Salt Lake City before and after an introduction of an additional LRT line. The analysis of different scenarios and on different network levels was performed using VISSIM microsimulation coupled with Siemens Next-Phase Software-in-the-Loop traffic controllers. The scenarios were evaluated for three different target years: 2013/2014, 2020 and 2025. Additional scenarios included alternative intersection configuration, with modified left turn operations at intersections of 400 South and Main, 400 South and State, and 400 South and 700 East.

Screenshot of the intersection simulation

Figure 2. Main Street and 400 South Intersection in Simulation

The analysis showed that the additional LRT line did not have significant impacts on traffic and transit operations. The highest impacts were experienced at intersections close to the Downtown area, mainly 400 South and State Street, and 400 South and Main Street, and North Temple and 400 West. The study also recommended potential signal improvements at these locations consisting of re-phasing, re-timing and modifying LRT preemption. The analysis also showed that it might be beneficial removing the shared lane sites at intersections along 400 South, since close to 70% of drivers are using the non-shared left turn lane, resulting in sub-optimal intersection operations.

This study was coordinated between UDOT, Utah Transit Authority, and other agencies.

This guest post was written by Milan Zlatkovic, University of Utah, Ivana Tasic, University of Utah, Marija Ostojic, Florida Atlantic University, and Aleksander Stevanovic, Florida Atlantic University, and was originally published in the Research Newsletter.

Photo of guardrail end section

This new Type G end treatment replaced an old Texas-turndown style end treatment on S.R. 87

Region Three’s Traffic and Safety staff focus on improved roadside safety by replacing guardrail and guardrail end treatments.

Griffin Harris, Region Three Traffic Engineer, led the effort to replace aging infrastructure with an eye toward safety. He managed the funding and installation of almost 3 miles of guardrail and the replacement of over 60 outdated Texas-turndown style guardrail end treatments with new Type G end treatments on six different state routes in Region Three.

For example, one project installed 2.25 miles of new guardrail in Indian Canyon on U.S. 191 between Helper and Duchesne. This area has steep drop-offs and the guardrail installation is a great safety improvement.

For more information about UDOT’s Barrier End Section (Crash Cushion) Program check out our website.

Citizen Reporting LogoThe UDOT Citizen Reporting Program enlists volunteers to report on current road conditions along specific roadway segments across Utah. Since the program’s launch in November 2013, UDOT has received over 1,800 road condition reports on critical routes throughout the state. The accuracy rate of the reports continues to be very high, with only 0.03% of incoming reports determined to be inaccurate.

The long term goal of adding Citizen Reporters to UDOT’s weather operations road reporting is to supplement current condition reporting on segments where drivers are already traveling. The Citizen Reporter Program provides the traveling public with a conduit to report their observations directly to UDOT, saving time and money. UDOT employees also use the Citizen Reporting app to submit their reports.

Since the UDOT Citizen Reporter Program was launched volunteer reporters have submitted reports on 119 of the 145 road segments, helping to fill in gaps in locations where UDOT does not have traffic cameras or Road Weather Information System (RWIS) units.

Graph showing citizen reports by day. The most were received in Decemenger 2013.The volunteer reports are especially valuable during winter storms when conditions change rapidly. During a large winter storm that occurred in the beginning of December 2013, UDOT Citizen Reporters submitted over 130 reports, helping the traveling public as well as National Weather Service meteorologists and UDOT staff.

How do you become a UDOT Citizen Reporter?

In order to become a UDOT Citizen Reporter, you will need to complete a brief training (either online or in person), take a short quiz and complete a sign-up form. The training takes approximately 10 minutes to complete. Once a volunteer has completed these steps, they will be provided with a login and PIN, and can begin submitting reports. Reports are submitted through the UDOT Citizen Reporting app, downloadable for Android and Apple devices from the Apple App Store or Google Play Store.

If you would like to become a Citizen Reporter, please follow this link to take the online training: www.udottraffic.utah.gov/training/citizenreporter. For more information or to schedule an in person training, email UDOTCitizenReporter@utah.gov.

The Employee Advisory Council met April 10, 2014. Items that were included in the discussion included:

  • Discussion regarding .25 percent discretionary increase
  • New legislation from the 2014 session
  • Tuition reimbursement
  • Employee recognition
  • Internal communications

Notes from the meeting are available below.

EAC April 2014 Summary

Information from previous meetings has also been posted on the blog.

Employee Advisory Council

A new study led by UDOT and funded through the FHWA Transportation Pooled Fund Program began in March and is progressing well. The study is number TPF-5(296), entitled “Simplified SPT Performance-Based Assessment of Liquefaction and Effects.” A research team from Brigham Young University (BYU) is performing the two-year study. Other state DOTs participating in the study include Alaska, Connecticut, Idaho, Montana, and South Carolina.

Liquefaction of loose, saturated sands results in significant damage to buildings, transportation systems, and lifelines in most large earthquake events. Liquefaction and the resulting loss of soil shear strength can lead to lateral spreading and seismic slope displacements, which often impact bridge abutments and wharfs, damaging these critical transportation links at a time when they are most needed for rescue efforts and post-earthquake recovery.

Most commonly used liquefaction and ground deformation evaluation methods are based on the concept of deterministic hazard evaluation, which is related to the maximum possible earthquake from nearby faults. Recent advances in performance-based geotechnical earthquake engineering have introduced probabilistic uniform hazard-based procedures for evaluating seismic ground deformations within a performance-based framework, from which the likelihood of exceeding various magnitudes of deformation within a given time frame can be computed. However, applying these complex performance-based procedures on everyday projects is generally beyond the capabilities of most practicing engineers.

The objective of the new study is to create and evaluate simplified performance-based design procedures for the a priori prediction of liquefaction triggering, lateral spread displacement, seismic slope displacement, and post-liquefaction free-field settlement using the standard penetration test (SPT) resistance. Many of the analysis methods used to assess liquefaction hazards are based on SPT resistance values since the SPT is commonly used in site soil characterization for building, transportation, and lifeline projects.

This study represents a worthwhile pilot study which could prepare the way for additional research with the U.S. Geological Survey to further the use of the simplified, performance-based method.

Figure 1: Liquefaction loading map (return period = 1,033 years) showing con-tours of CSRref (%) for a portion of Salt Lake Valley, Utah

Figure 1: Liquefaction loading map (return period = 1,033 years) showing con-tours of CSRref (%) for a portion of Salt Lake Valley, Utah

The key to the simplified method is the use of a reference soil profile in development of liquefaction loading maps which are then used with the site’s soil data to estimate effects of liquefaction. An example map is shown in Figure 1, where CSRref represents a uniform hazard estimate of the seismic loading that must be over-come to prevent liquefaction triggering, if the reference soil profile existed at the site of interest.

Derivations for simplified performance-based liquefaction triggering and lateral spread displacement models have been completed in the study. Validation efforts have shown that the simplified results approximate the full performance-based results within 5% for most sites that were evaluated.

A summary of the study work plan and copies of current reports from the study are available at the TPF-5(296) study website.

This guest post was written by Kevin Franke, Ph.D., P.E., from BYU, and David Stevens, P.E., Research Program Manager, and was originally published in the Research Newsletter.

When Region Three began preparations for reconstructing State Street from 1860 North in Orem to 100 East in Pleasant Grove, the focus was on widening to three travel lanes in each direction plus a center turn lane.

The project team prepared plans for new asphalt pavement; traffic signal upgrades; curb, gutter, sidewalk and pedestrian ramp installations and reconstruction of the intersection at State Street and 400 North in Lindon. But what makes this project memorable was the partnership with the cities of Orem, Lindon and Pleasant Grove that brought about the addition of striped bicycle lanes to the project scope.

“We have been working with UDOT Central Planning and Mountainland Association of Governments to identify opportunities for bike improvements,” said Region Three Program Manager Brent Schvaneveldt.

“With UDOT’s emphasis on integrated transportation and these other bicycle connectivity discussions happening, we wanted to take the cities’ request for bike lanes seriously and take a hard look at whether they could be added into the design and construction.”

With the widening, repaving and re-striping already planned for State Street, the opportunity to reallocate space and stripe bike lanes made sense. But it wouldn’t have happened without the buy-in and support from local governments.

“Local government collaboration is key to making our transportation network work for the people who use it. Especially on a roadway like State Street that serves local trips as well as regional travel,” Brent said. “This is a great example of local government input helping us better serve the needs of a variety of roadway users.”

Photo of all of the IMT trucks lined upUDOT’s Incident Management Team (IMT) vehicles exist to help motorists when they have car trouble and to support the Utah Highway Patrol (UHP) during any roadway incident. UDOT is focused on quick clearance of traffic incidents to minimize the risk to the first responders and to have travel lanes reopened as soon as possible.

UDOT’s IMT program has 14 trucks operating in all four of UDOT’s regions. The trucks carry a variety of equipment, including jacks, gasoline, air compressors, battery packs, oil dry, first aid kits and various tools for minor roadside repairs. UDOT chose to operate larger vehicles than some other states for the IMT program. The benefits are better visibility to passing motorists and the ability to carry more equipment.

Image of Twitter comment thanking an IMT driver for help chaning a tire.

A thank you received by UDOT Traffic on Twitter

IMT drivers are required to attend several trainings per year including training on hazardous material spills, emergency traffic control, medical and FEMA classes. Recently, the IMT drivers completed their certifications in emergency vehicle operations at the UHP training track near Camp Williams. The drivers learned about proper backing techniques, defensive driving, their vehicle dynamics and proper emergency traffic scene safety.

Image of a tweet sent thanking IMT for they help while stranded on I-80 near the airport.

Thank you recived by UDOT Traffic on Twitter.

The IMT program has helped hundreds of motorists over the last several years. Some people refer to the IMT drivers as “professional good samaritans.” Disabled vehicles on a freeway create a safety hazard, especially when the disabled vehicle is blocking a travel lane. The likelihood of a secondary crash resulting from congestion increases by almost 3% for every minute that the lane is blocked. Approximately 20% of all crashes are called secondary crashes, or a crash that can be traced to an original incident.

This guest post was written by Jeff Reynolds, Roadway Safety Manager.

Efficiencies within UDOT often generate cost savings for the public and the Department through better utilization of resources and innovative technologies. At the end of each year, UDOT prepares an efficiencies report which summarizes key efficiency initiatives from the year. The annual report fulfills a requirement for UDOT to describe the efficiencies and significant accomplishments achieved during the past year to the State Legislature. UDOT Senior Leaders use the report in presentations during legislative committee meetings.

Following are the key efficiency initiatives summarized in the FY 2013 report:

  • Bicycle Detection and Pavement Markings
  • Flashing Yellow Arrow for Left Turns
  • Reflectorized Yellow Tape on Signal-Head Back Plates
  • Portable Weather Station for Advance Warning of Debris Flows
  • Audio Over IP Highway Advisory Radio in Utah County
  • Commercial Vehicle Bypass (PrePass)
  • Partnered Fiber-Optic Cable Installations
  • Resolving Utility Conflicts through a Preserve and Protect Approach
  • Utah Prairie Dog Programmatic Agreement
  • Performance-Driven Programming
  • Energy-Efficient LED Lighting Upgrades in Department Facilities
  • iMAP GIS Tool
  • Improved Decision Making Using Mobile Data Collection
  • MMQA Data Collection Teams
Photo of a flashing yellow signal

Flashing Yellow Arrow left-turn phasing

One example from the 2013 report is the improved safety at intersections that are changed from Protected/Permissive to Flashing Yellow Arrow left-turn phasing. UDOT and other jurisdictions throughout Utah are among the first in the nation to implement flashing left-turn arrows. Potential annual public cost savings per installation ranges from $17,745 to $2,769,000 from reduced crashes.

Photo of rock and mud covering the highway

Debris flow across S.R. 31 in Huntington Canyon

Another example from 2013 is the use of a portable weather station to provide advance warning of debris flows and flooding at the Seeley burn scar near S.R. 31 in Huntington Canyon. Using the station contributed to over-all safety, minimized equipment losses, reduced response time, and minimized impact to commerce. An estimated $50,000 was saved through reduced risk to field crews, motorists, and equipment.

UDOT Research Division staff coordinate each year with UDOT Senior Leaders and the Communications Office to collect and compile write-ups on the past year’s key efficiency initiatives. This process will start again in August for FY 2014. We look forward to receiving “game changing” efficiency topics from all Regions and Groups that will potentially be included in the annual report.

The 2013 and earlier annual reports are available online at www.udot.utah.gov/go/efficiencies.

This guest post was written by David Stevens, P.E., Research Project Manager, and was originally published in the Research Newsletter.

Photo of the State Street and 1320 South intersection in Provo

New signals at Provo State Street and 1320 South.

Existing traffic signals have been updated to newer equipment that includes controllers that send real-time data about the signal operations to the Traffic Operations Center.

With the upgraded controllers, UDOT can troubleshoot issues remotely such as noticing a stuck pedestrian button or verifying signal timing.

Traffic engineers can track data that used to require manual labor such as traffic speeds, traffic volumes and percent arrival on green.

Photo of the inside of a signal cabinet

A signal cabinet at State Street and 1320 South. The cabinet contains a controller that gathers and transmits real-time traffic data for remote analysis and optimization of the system.

Out of 249 signals operated by UDOT in Region Three, 211 have been upgraded to gather this real-time traffic data for analysis and optimization of the system. “Small adjustments can sometimes make a big difference for our traffic operations,” said
Adam Lough, Region Three Engineering Manager.

“The upgraded signal controllers allow us to make these adjustments and monitor how the intersection is operating without being on-site.”

The opportunity to recognize excellent, dedicated and forward-thinking UDOT employees officially comes once a year, and the UDOT Traffic Management Division (TMD) was happy to identify several deserving staff through this process. It is important to pause and recognize outstanding employee achievement and celebrate the employees who continually go above and beyond to ensure great customer service to the public.

Headshot of Kelly Burns

Kelly Burns

This year, Kelly Burns was selected as the TMD Employee of the Year. Kelly is currently managing a project to develop freeway performance measures for congestion monitoring. She also supports UDOT’s four Regions for traffic modeling. Because of Kelly’s hard work and dedication, the new Speed Profile report for I-15, which identifies bottlenecks, was completed. The Speed Profile report will also be an excellent resource for effective future planning efforts. Kelly demonstrates a commitment to her job, co-workers and the traveling public every day. Congratulations, Kelly!

Headshot of Jeff Williams

Jeff Williams

Jeff Williams was selected as the TMD Leader of the Year. Jeff manages an exceptional team of meteorologists. His group is responsible for several innovations that contribute to safer roads, less materials costs and better service to the public. The new winter road weather index uses data from UDOT’s Road Weather Information System (RWIS) network to determine the intensity of a storm and the effectiveness of UDOT’s snow removal efforts. The efforts of Jeff and his team keep UDOT in the national spotlight for traveler information weather operations. Congratulations, Jeff!

Headshot of Keith Wilde

Keith Wilde

The TMD Career Achievement Award goes to an employee who has a longstanding history of excellency. This year, Keith Wilde was the award recipient. Keith has over thirty years of experience and leads the traffic signal field technicians. Keith has been instrumental in ensuring UDOT’s traffic signals are truly “world-class”. Keith is the resident expert on electronics for traffic signals. Utah residents may see Keith at a signalized intersection nearby a large special event helping with traffic flow. The UDOT TMD is very fortunate to have Keith and appreciates all of his hard work. Congratulations, Keith!