1 / 15

I-74 Corridor Ramp Metering

I-74 Corridor Ramp Metering. Green Township Trustee Meeting May 24, 2004. Statewide Safety & Congestion Initiative. Statewide Historical Crashes. The New Highway Safety Program. Safety “Hot Spots” Defined by crash frequency Targets Urban freeways Highway Safety Program

alpha
Download Presentation

I-74 Corridor Ramp Metering

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. I-74 Corridor Ramp Metering Green Township Trustee Meeting May 24, 2004

  2. Statewide Safety & Congestion Initiative

  3. Statewide Historical Crashes

  4. The New Highway Safety Program • Safety “Hot Spots” • Defined by crash frequency • Targets Urban freeways • Highway Safety Program • Defined crash rate, frequency, severity, etc. • Targets Rural freeways and non-freeways • Targets Urban freeways and non-freeways

  5. GOALS • Established Crash Reduction Goals • Continual improvement in crash reduction • By 2008, 1.00 fatalities per 100 MVMT • By 2015, 10% reduction in the total number of crashes (40,000) • By 2015, 25% reduction in the total number of rear end crashes (25,000)

  6. What are Ramp Meters? • Traffic signal on an entrance ramp to a freeway • Release one or two vehicles at a time • Break up long platoons of merging vehicles

  7. Operations • Balance Side Street Demand • Cycle Length • 4 to 15 seconds • Multi-Lane Ramp • One or two vehicles per green • Staggered-metering • Time-of-Day or Demand Responsive • Queue Detection • Demand & Passage Detection • Merge Detection • Mainline Detection

  8. What Ramp Meters Can Do? • Realized Benefits • Reduce crashes by 15-50% • Improve travel speeds by 8-60% • Provide more uniform traffic flow

  9. Nationally • More than 33 US metro areas • Started in Chicago & Detroit in 1960s • Case Studies • Twin Cities • Madison

  10. Twin Cities – Case Study • Without Ramp Meters • 9% reduction in freeway volume • 22% increase in freeway travel times • 91% reduction in reliability of travel time • 26% increase in crashes • Support for meters increased from 60% to 70% • Benefit/cost = 15:1 • Use faster cycle times / fewer meters

  11. Madison – Case Study • 5 Ramp Meters Deployed • Preliminary Results • Reduced Crashes – 50% • Especially Rear-ends • Improved Highway Throughput – 30% • High Driver Compliance - 96% • Reduced Speed Variability • Some Travel Time Increase • Traffic diversion Was Not Observed • Public Acceptance • 92% - improved safety

  12. Concerns… • Aren’t signals at ramps already metering? • Ramp signals operate differently • Ramp signal allow many (15 to 20) vehicles to enter the freeway at once. • Ramp meter only allow one or two vehicles to enter at once. • Is I-74 bad enough yet? • ODOT’s HSP and Hot Spot list • Approximately 850 crashes (2000-2002) on the corridor with approximately 575 eastbound crashes • Travel speed are low during the morning peak hour

  13. Concerns… • Will the ramp meter backup traffic on surface streets? • Ramp meter will not exacerbate the queuing problem • Why install ramp meters on I-74 1st? • Safety Program identified the problem – ramp meters were a potential medium cost solution. • ODOT developed a statewide ramp metering protocol. • More to come in all areas of the state.

  14. Schedule Public Meeting Steering Committee Meeting

  15. Conclusions • Ramp Meters improve safety • Ramp Meters increase traffic flow • Ramp Meters will not exacerbate surfacing street queuing • Additional Technical Studies • Public Outreach • Driver Survey Next Steps

More Related