Key issues discussed at the Lane Widths and Liability Conversation Circle included the following:
Statistically, assuming a travel speed of 45MPH, the difference in safety between lanes greater than 10” and less than 10’ is indistinguishable.
A street must add value and context to its environments.
Some of the considerations in determining lane widths as related to the movement of freight include work zones, oversize permitting, travel speed differential, intermodal connectors, complete streets, statewide and metropolitan freight plan, and study/inventory of state size and weight limits.
A key consideration in determining lane widths as related to public transportation is that while the minimum travel width for a bus is 10’ 6”, the minimum lane width for a bus pullout can be 10’.
From an urban perspective, lane widths must focus on urban value, design vehicle, minimum lanes, and “add on” design elements such as shoulders.
The shared lanes concept can be a viable way to achieve a successful balance in the adaptation of the narrow lane concept.
The use of 10’ interior lanes is another way of accommodating bike lanes, if desired
Engineering judgment in addressing the design of travel lanes as related to the surrounding environment is vital to meeting user needs, There is limited data available in determining the cost/benefits of applying the narrow lanes concept.