Keeping Wisconsin Moving: An Overview of WisDOT’s DMS Travel

TimesKelly Langer, WisDOT, Freeway Operations Supervisor

Southeast Wisconsin at a glance

• City of Milwaukee population: 676,000

•Milwaukee Co. population: 1,500,000

• Heavily traveled freeway corridors:

I-94 EB / WB from downtown to Hwy 100 (*AADT: 153,000)

USH 45 NB / SB North of I-94 (AADT: 137,000)

I-94 NB / SB South of I-894 (AADT: 143,000)

*AADT= Average Annual Daily Traffic

WisDOT Traffic Operations Center

• 36 DMS on freeways and major arterials

• 125 ramp meters in metro Milwaukee

• 100 cameras on Milwaukee area freeways and major arterials

• Control Room operated 24/7

• Highway Advisory Radio (HAR)

• Crash Investigation Sites

• Media Partnerships

Traffic Incident Management Enhancement Program - TIME

• Bi-monthly meetings of law enforcement, public partners, private partners, universities

• Sub-committee sessions for special events, incident management, corridor traffic management, outreach and public information

• ITS allows the freeway corridor to be viewed and operated as a single entity, which aids in managing congestion

• Dealing with 30% increase in volume over the past ten years

WisDOT DMS Timeline1993

• Local traffic reporter began giving travel times as part of his traffic reports via airplane

1994

• WisDOT began using loop detectors that were installed in 1970’s to calculate speed/volume

1995

• Began limited DMS travel time publishing

• Only published after heavily verified by test drives

• Only displayed during control room hours – aprox. 10 hours per day

WisDOT DMS Timeline1998

• Improved reliability of travel times and computer network1999

• More DMS added – more travel times added

• Some new travel times based on public input

• Travel times added to WisDOT internet pages

2000

• Travel times displayed 24/7 on every DMS

• Continue to monitor travel times and adjust as appropriate2004

• “Time of Day” travel times began

WisDOT DMS Usage

• Travel Times

• Incidents

• Amber Alert

• Special Events

• Construction and weather information

• Congestion information

How Travel Times are Calculated

Website updates every 3 minutes

Updates every 60 seconds

FTMS* Server:

Average Speed/Known Distance = Time

Traffic Operations Center

In pavement detection:

• ¼ mile spacing in urban areas

• 2 mile spacing in rural areas

*FTMS= Freeway Traffic Management System

WisDOT Travel Times•All corridors in metro-Milwaukee have at least one travel time (Four inbound corridors and five outbound corridors)

• Destinations for travel times were chosen by interchanges or major cross streets – frequently use static signed streets to allow travel times to be useful for visitors as well as commuters

• No data from “probe” vehicles, detector data only

Arterial DMS - Roadside

WisDOT Travel Times• Simple requirements were developed for each travel time – travel times on DMS round up

• Travel Times will not display if 33% of the links are invalid

• WisDOT internet site displays travel times to the second

Travel Time Calculations

• The shorter the travel time distance (Point A to Point B), the more accurate the travel time is likely to be for the driver

•If the FTMS server is not operating properly, computer program removes travel times from the DMS’ within 10 minutes

• 66% of the detectors have to be reporting valid data for travel times to be published (i.e. at least one lane of data can be non-reporting or have 33% detector failure to display the travel time)

Data Extractor Enables WisDOT to retrieve volume, speed, and occupancy data from the SE Wisconsin Freeway

Used to retime Ramp Meters while using up-to-date data

Used to prepare reports for various different agencies (Sheriff’s Dept., media, public)

Obstacles to posting Travel Times

• Maintenance of detectors and verifying detector accuracy (Making sure reporting links are sending accurate data to the communications server)

• Developing consensus among WisDOT staff with public and media input as to which initial routes to display

• Developing meaningful travel time messages that would fit on signs

• Putting confidence in reliability of network and software before allowing messages to display without immediate oversight

• Ongoing travel time verification

Public Involvement and Feedback• No formal campaign for introducing travel times

due to the length of time of implementation

• News agencies requested several interviews over the course of implementation

• Initial skepticism regarding accuracy was quickly replaced by motorists depending on the travel times

• No formal study of public perception has been conducted

“You’ve spoiled us with the travel time availability…”

“I love your travel time website! I surf it every day!”

“The travel times help me determine which route to take when I get to the Hale Interchange; if both routes are backed up I can exit at Layton Ave.”

“I do appreciate the ability to view this travel time information. It is very helpful to the general public.”

WisDOT’s Future Travel Time Plans

• WisDOT is developing software to report travel times via Highway Advisory Radio – AM 1610 (“Text to Voice”)

Travel Time Facts

• Longest DMS travel time route is 20 minutes in free-flow traffic

• Shortest DMS travel time route is 6 minutes in free-flow traffic

• 33 DMS and ADMS signs display travel times in southeastern Wisconsin (of 36 signs)

• Travel time routes are displayed on the public WisDOT website – various news agencies and other sites link to the data

THANK YOU!

QUESTIONS??

Kelly Langer - 414-227-2160 – kelly.langer@dot.state.wi.us

Wisconsin Department of TransportationTraffic Operations Center633 W. Wisconsin Ave. Suite 1200Milwaukee, WI 53203

414-227-2166 – milwaukee.toc@dot.state.wi.us