1. Intersection Control Evaluation (ICE)

2. Outline  Background  ICE Process  Impacts  Current Status

3. Background  Signal Justification Reports –Completed during final design –Document warrants –Straightforward, but no consideration of other alternatives

4. Background  Increased Traffic Control Options –All-way stop –Signal –Roundabout –Access Management –Grade Separation –Non-Traditional  Continuous flow  Michigan left

5. Background  Need process to analyze intersection traffic control options  Document analysis and selection of preferred alternative

6. Why Change?  All intersection control decisions documented  Early decisions help limit scope creep  Improve coordination and collaboration with local agencies  All intersection control options considered on an equal basis

7. The ICE Process  Required on all trunk highways  State-Aid is considering adoption  Not required for two-way stop or uncontrolled intersections  Written by licensed engineer  Approved by the District Traffic Engineer

8. The ICE Process  Goal: –Consider technical, financial, and political aspects of each control alternative –Select optimal intersection control

9. The ICE Process  Phase 1- Scoping –Complete as early in the project development process as possible –Can occur prior to project programming –Determine feasibility of traffic control options  Phase 2- Alternative Selection –Layout development –Identify recommended traffic control

10. The ICE Process

11.  Phase 1- Scoping –Conduct a technical analysis of options –Initial public acceptability of options –Interim report and recommendations

12. The ICE Process  Phase 1- Scoping –Warrant analysis  Traffic volumes (vehicle/pedestrian/bicycle), crash history, delay –All-way stop –Signal –Roundabout considered warranted if meets either AWS or signal warrants

13. The ICE Process  Phase 1- Scoping –Justification  Safety  Congestion  Intersection spacing  Future traffic volumes  Percentage of turning traffic  Vehicle types and percentages  Sight distance  Right of Way  Available funds  Local support

14. The ICE Process  Phase 1- Scoping –Crash Evaluation  Crash diagram with most recent 3 years of data for existing intersections  Estimate anticipated crashes for each traffic control alternative  Calculate crash reductions per year  Calculate crash cost reduction per year

15. The ICE Process  Phase 1- Scoping –Capacity Evaluation  Existing AM and PM peak hour volumes  Design year AM and PM peak hour volumes  Existing and design year pedestrian and bicycle volumes  Design vehicle  Horizontal, vertical, and site constraints –District Traffic Engineer to determine acceptable level of analysis (including software)

16. The ICE Process  Phase 1- Scoping –If only one viable alternative comes out of Phase 1, ICE is complete –For corridor or planning study, Phase 1 evaluation may be sufficient –District Traffic Engineer to determine appropriate level of analysis for each project

17. The ICE Process  Phase 1- Scoping –Preservation projects and signal revisions still require memo/letter to be submitted for approval –All decisions and evaluation should be documented in final ICE report

18. The ICE Process  Phase 2- Alternative Selection –Develop conceptual layouts –Determine ROW impacts and estimated costs –Estimate construction costs –Assess public involvement and acceptance –Prepare final ICE document

19. The ICE Process  Phase 2- Alternative Selection –Other considerations  Skew angle  Offset approaches  Odd number of approaches  Closely spaced intersections  Approach grades

20. The ICE Process  Phase 2- Alternative Selection –More detailed capacity analysis  AWS- Synchro/SimTraffic  Signals- Synchro/SimTraffic  Roundabouts- RODEL  Roundabouts in series or roundabouts within traffic control system- VISSIM

21. The ICE Process  Phase 2- Alternative Selection –RODEL is a roundabout design tool (empirically based) –Synchro/SimTraffic and VISSIM are analysis tools (gap acceptance based)

22. The ICE Process  Phase 2- Alternative Selection –Other considerations  Coordinated signal systems  Interregional Corridors (IRC) –Compare to recommendations of corridor study –Address impacts on IRC performance

23. Mn/DOT Impacts  Dependent upon two major factors –Project origin –Size and/or type of project  For internal project, Mn/DOT completes analysis and ICE report  For external project, outside agency or consultant completes ICE  District makes decision on the scope/detail of the analysis

24. Mn/DOT Impacts  Internal Project Roles –Capacity and safety analysis (Traffic) –Public involvement (District) –Conceptual layouts and impacts (Design) –Final report documentation (Traffic)

25. Other Impacts  Program and Project Management System (PPMS) modification  New software and training  Increased internal and external coordination  Districts document their process (warrants and justification)

26. Current Status  Technical Memo No. 07-02-T-01 (03/20/07)  Actions in Metro –Purchase of Rodel and VISSIM –Drafting a detail of “how to” complete and ICE study –Simplifying the capacity analysis

27. Current Status  Actions in Metro –Reviewing ICE documents –Timing of implementation (FY 2008)

28. QUESTIONS?