An Analysis of VDOT’s Sight Distance Requirements Relative to Context-Sensitive Designs

Details

• Creators:
  Lamsal, Sharad ; McKinney, Jonathan ; Dougald, Lance E. ; Chen, Tong Donna
• Corporate Creators:
  Virginia Transportation Research Council (VTRC) ; University of Virginia
• Corporate Contributors:
  Virginia. Department of Transportation ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  Best Practices Context Sensitive Design Crash Modification Factors Highway Safety Intersections Sight Distance Urban Areas Visibility
• Publication/ Report Number:
  VTRC 26-R27
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Virginia
• Edition:
  Final Report
• Corporate Publisher:
  Virginia Transportation Research Council (VTRC)
• Abstract:
  Intersection sight distance (ISD) requirements are intended to enhance safety by ensuring visibility at intersections. However, in dense urban areas, these requirements can preclude elements of the urban streetscape, such as street trees, on-street parking, and transit infrastructure, and can restrict compact mixed-use developments, such as traditional neighborhood developments. Although literature on the safety impacts of ISD is plentiful, little of it is tailored to low-speed urban environments, an area of interest to the Virginia Department of Transportation (VDOT). Accordingly, this study examined the existing state of practice on ISD guidelines and conducted a safety analysis focused on low-speed urban intersections. This report first reviews literature and policies across state departments of transportation (DOTs) and localities. Second, it presents findings from a survey of 17 state DOTs, 34 Virginia localities, and 24 VDOT residencies on current practices related to implementing ISD standards. Then, it provides details of a safety analysis examining how ISD impacts crash occurrence for 359 intersections in Virginia, distinguishing between T-intersections and four-leg intersections and stratifying by speed ranges (low speed ≤ 25 mph and high speed ≥ 30 mph).
• Format:
  PDF
• Funding:
  124252
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:a274e321ac25dc3d0cfb41d446a15a50e7573324ddfcc89af065c5e8aa6a287bc7b5977632f86afb4ad68168bc22e729aa97e8b5f4627a28a59d53687258da9a
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/88719/dot_88719_DS1.pdf
• File Type:
  [PDF - 6.28 MB ]