The U.S. Federal Highway Administration (FHWA) released a video that explores the potential operational and safety benefits communities can achieve from installing modern roundabout intersections. The benefits of roundabouts include increased safety, improved traffic flow, reduced emissions, lower costs, and community livability. The keys to successful installation of roundabouts include proper design, public involvement, and stakeholder support. For more information about modern roundabouts, visit the FHWA Office of Safety.

Example of a Roundabout in Salt Lake City

Photo Courtesy of Dan Burden

Traffic & Parking Control Co., Inc. (TAPCO) and the Great Lakes Transportation Enterprise Institute (GLTEI) are sponsoring a Transportation Workshop on July 30, 2010, from 7:00 a.m. to 3:00 p.m. CDT. Frank Busalacchi, secretary of the Wisconsin Department of Transportation, will give welcoming remarks and Rick Bergholz will introduce the GLTEI. The remainder of the workshop will be dual track and sponsored by GLTEI and TAPCO. The GLTEI agenda includes presentations on the impact of Industry-University Collaboration, 2009 Manual on Uniform Traffic Control Devices (MUTCD) regulations, WisTransPortal Transportation Operations Data Hub, Sustainability, and Emergency Traffic Response Solutions. The TAPCO agenda includes presentations on Integrating Emergency Communications & License Plate Recognition, Adaptive Transit Priority Systems, Municipal Wireless Communication Solutions, Time Travel Measurement, and Sign Retroreflectivity. For more information or to RSVP, contact Christine Merritt (chrism@tapconet.com or 262-649-5108).

The Transportation Safety Advancement Group (TSGA) will sponsor a webinar discussing the details of the Fort Hood shooting incident with a focus on the integration between the military and civilian responders. The workshop will focus on emergency response and management protocols, strategies, and technologies, including communications between and among police, emergency medical services, and public safety dispatch personnel. The presenters will discuss successes, failures, and lessons learned. They will also highlight emergency response activities of local and regional emergency responders and will review operations strategies and technologies at the time of and in response to the incident.

The free webinar will take place on Tuesday, August 3, 2010, from noon to 3:00 p.m. CDT.                          

The City of Naperville and Illinois Department of Transportation (IDOT) are holding an open house regarding the Route 59 Expansion Project. Attendees will learn about diverging diamond interchanges (DDI), an innovative design which is being considered for the I-88/Route 59 interchange. Compared to the conventional interchange design, the DDI offers many benefits, including fewer conflict points, reduced vehicular delay, and reduced environmental impact. No formal presentations will be given, but representatives from the City of Naperville, IDOT, and Teng and Associates, Inc. will be available to answer questions.

For more information regarding DDI, also referred to as double crossover diamond interchange (DCD), the U.S. Federal Highway Administration just released a tech brief [PDF]. The draft GO TO 2040 regional comprehensive plan endorses the development of innovative designs that reduce delay and improve safety.

This open house will take place Wednesday, July 14, 2010, from 5:00 to 7:oo p.m. at the Naperville Municipal Center, Council Chambers, 400 S. Eagle St., Naperville, IL.  

First U.S. DDI interchange at I-44 and Route 13 in Springfield, MO.

Source: Missouri Department of Transportation

As part of the CMAP Congestion Management Process, staff has compiled performance measures for the regional freeways for 2009. The performance measures include congestion scans, travel time index, planning time index, and congested hours. Congestion scans show average speed by milepost by time of day for the freeway segment.

The travel time index is a measure of average congestion and indicates the average extra travel time required during peak period congestion. Travel time index is a ratio of the average peak period travel time compared to the free-flow travel time. For example, a value of 1.20 means that average peak travel times are 20 percent longer than free-flow travel times.

The planning time index is a measure of reliability. The planning time index is defined as the ratio of the total time needed to ensure a 95percent on-time arrival to the free-flow travel time. For example, a value of 1.4 means that, to arrive on-time 95 percent of the time, a traveler should budget an additional 8 minutes for a trip that takes 20 minutes during off-peak, free-flow conditions.
Congested hours are an indication of how many hours per day a facility is congested. Technically, "congested hours" are defined as the average number of hours in which at least 20 percent of the vehicle miles traveled (VMT) on the instrumented segment is congested. For this measure, congestion is defined to occur when link speeds are less than 50 mph.

Chicago region freeway performance measures are available on the CMAP website.

I-290 from Canal St. to Wolf Rd. 2009 congestion scan.

Welcome to Green Signals, the CMAP transportation operations blog. Here, we will identify and promote the latest news, resources, funding opportunities, and training related to transportation operations. Green Signals will have a regional focus, but will keep you up-to-date on state, national, and international developments and news as well. The blog will cover all topics related to transportation operations, including transit, arterial and freeway management, freight, incidents, special events, training, funding opportunities and strategies, traveler information technology, design, and available data sources.