Advanced Search Options
Unsignalized Intersection Improvement Guide - Practical guidance for improving the safety, mobility, and accessibility at unsignalized intersections.

Treatment Alternatives List

The UIIG treatments are organized by the following categories:
Traffic Control Devices, Geometric Improvements, Shoulder and Roadside, Pavement Surface, Other Engineering, and Enforcement.

Traffic Control Devices

  1. Install a YIELD Sign
  2. Install a STOP Sign
  3. Implement All-Way Stop Control
  4. Install an Intersection Control Beacon
  5. Install a Stop Line
  6. Install a Yield Line
  7. Install a Stop Beacon
  8. Install a Traffic Control Signal
  9. Prohibit Turn Movements Using Signs
  10. Re-Time Adjacent Traffic Signals
  11. Install Intersection Warning Signs
  12. Install Advance Traffic Control Warning Signs
  13. Install an Intersection Conflict Warning System (ICWS)
  14. Install Post-Mounted Reflective Delineators at the Intersection
  15. Increase the Size of a Regulatory or Warning Sign
  16. Add a Duplicate Regulatory or Warning Sign
  17. Install a Warning Beacon on a Standard Regulatory or Warning Sign
  18. Use LED Units within a Regulatory or Warning Sign
  19. Install Reflective Panels on Sign Posts
  20. Add Retroreflective Sheeting to the Perimeter of a Warning Sign
  21. Install Red or Orange Flags to a Regulatory or Warning Sign
  22. Install Wider Longitudinal Pavement Markings
  23. Install Center Line Pavement Markings in a Median Crossing
  24. Install Center Line Pavement Markings on the Minor Road Approach
  25. Install Dotted Line Pavement Markings
  26. Install Lane Assignment Pavement Markings or Signing
  27. Install Pavement Word and/or Symbol Markings
  28. Install Dotted Turn Path Markings
  29. Install Raised Pavement Markers
  30. Install or Modify Crosswalk Markings
  31. Install a Pedestrian Hybrid Beacon (PHB)
  32. Install a Rectangular Rapid-Flashing Beacon (RRFB)
  33. Install Bicycle Lane Pavement Markings Across the Intersection
  34. Install Signs Warning of Pedestrians and Bicyclists
  35. Add a Beacon to a Standard Speed Limit Sign
  36. Install Speed Reduction Pavement Markings
  37. Install a Dynamic Speed Feedback Sign

Geometric Improvements

  1. Eliminate Turn Movements Using Design Alterations and Channelization
  2. Replace Left-Turn and Through Movements with a Right-Turn/U-Turn Combination
  3. Close One or More Legs of the Intersection
  4. Convert a Four-Legged Intersection to Two T-Intersections
  5. Convert Two Offset T-Intersections to a Single Four-Legged Intersection
  6. Close a Median Opening
  7. Realign the Intersection Approach to Reduce or Eliminate the Skew Angle
  8. Modify the Horizontal and/or Vertical Alignment of an Intersection Approach
  9. Reduce an Intersection Curb Radius
  10. Increase an Intersection Curb Radius
  11. Install a Raised Intersection
  12. Reduce the Width of the Travel Lanes on the Major Road Approach
  13. Install a Splitter Island on the Minor Road Approach
  14. Install a Left-Turn Lane on the Major Road
  15. Extend the Left-Turn Lane
  16. Install a Left-Turn Acceleration Lane
  17. Provide Offset to Left-Turn Lanes
  18. Install a Right-Turn Lane along the Major Road
  19. Extend the Right-Turn Lane
  20. Install a Right-Turn Acceleration Lane
  21. Provide Offset to a Right-Turn Lane
  22. Install a Bypass Lane at a T-Intersection
  23. Provide a Pedestrian Refuge Island
  24. Install a Roundabout
  25. Install a Mini-Roundabout
  26. Install a Residential Traffic Circle
  27. Install Curb Extensions at the Crosswalk
  28. Restrict Driveway Access

Roadside / Shoulder

  1. Clear the Intersection Sight Triangles
  2. Eliminate Parking at or near the Intersection

Pavement Surface

  1. Install Transverse Rumble Strips on the Intersection Approach
  2. Install a High-Friction Surface Treatment on the Intersection Approach

Other Engineering

  1. Install Intersection Lighting
  2. Relocate a Bus Stop


  1. Conduct Targeted STOP Sign Enforcement
  2. Conduct Automated STOP Sign Enforcement
  3. Conduct Targeted Speed Enforcement
  4. Conduct Automated Speed Enforcement