The safety of collector roads has, for some years, been a matter of conjecture amongst urban designers and traffic engineers. Most contemporary residential estates continue to include traditional collectors in their plans to serve both access and traffic functions. However, little quantitative research has been conducted to evaluate them. Five residential subdivisions typifying contemporary road configurations were selected for analysis. Accident summaries for each area were tabulated, and accident costs were apportioned on a per-lot basis. The analysis indicates that more than half of all the accidents involved a collector road. The results also reveal that a high proportion of mid-block accidents (at least 46 per cent) involved collisions with parked cars or driveway manoeuvres, and would probably not have occurred if parking and residential driveways were not present. Evidence is presented to indicate that whole subdivisions designed around collector roads with no driveways or on-street parking would be safer than conventional practice (A).
Samenvatting