Managed Lanes

Managed Lanes (Definition)

Any general lane that has restricted or specialized use for a specific mode or user either during the entire day or certain times. It is a regular lane that is “managed” to increase efficiency. in some way (usually throughput).

Graph- Top peak flow, 200 is jam density (free flow speed on the left side), Right side is congested

What are managed lanes?

High Occupant Vehicle Lanes, High Occupancy Toll Lanes, Alternative Fuel Vehicle Lanes, Truck Lanes, Bus Lanes, Contra-flow Lanes….

What are not managed lanes?

Turning lanes, Bicycle lanes, and sidewalks…

Purpose of High Occupant Vehicle Lanes (HOV)

HOV lanes provide a lane especially for vehicles with two or three people. Provide priority for carpoolers, reducing car demand while maintaining person demand (remember, transportation is a demand derived from activity, which we want)

Design Characteristics of High Occupant Vehicle Lanes (HOV)

No lane change control, limited entrance and exit, buffer separated, and dedicated ramp infrastructure.

Impacts of High Occupant Vehicle Lanes (HOV)

Slugging or casual carpool, Park and ride, and bus priority

Pros of High Occupant Vehicle Lanes (HOV)

HOV lanes increase efficiency by encouraging carpooling and increasing the person-capacity of the road

Cons of High Occupant Vehicle Lanes (HOV)

HOV lanes are under-utilized, reducing the overall capacity of the system. HOV lanes don’t increase occupancy of the vehicles, they only give priority to existing carpoolers or families.

What are recent finding of High Occupant Vehicle Lanes (HOV)

HOV lanes can reduce congestion (increase flow), especially when it is at capacity at the bottleneck.

Purpose of High Occupant Toll Lanes (HOT)

HOT lanes provide a lane especially for vehicles with two or three people, but allow single occupant vehicle (SOV) drivers to buy in and pay a toll to enter.

Provide free priority for carpoolers, reducing car demand while maintaining person demand, but also increase utilization of lane by select single occupant vehicles—- generally public-private partnerships.

Design characteristics of High Occupant Toll Lanes (HOT)

Automated system to charge toll to SOV (RFID), Carpoolers don’t pay toll, and automated enforcement.

Impacts of High Occupant Toll Lanes (HOT)

Increases capacity, provides travel time reliability “insurance, charges based on congestion levels (rational way to charge)

Purpose of Alternative Fuel Vehicle (AFV) Lanes

Alternative Fuel Vehicles are promoted in many cities and a goal is made to give them priority.

Provide priority to alternative fuel vehicles (hybrids, CNG, etc.). This is another way to fill excess capacity while maintaining free-flow HOV lanes.

Design Characteristics of Alternative Fuel Vehicle (AFV) Lanes

All priority is given in areas with existing HOV lanes and AFV sometimes have limited allowances.

Some impacts of Alternative Fuel Vehicle (AFV) Lanes

Increases capacity, gives the most sustainable vehicle(s) a free pass, foregoes these vehicles creating a sort subsidy.

Purpose of Truck Priority or Restriction Lanes

Trucks have a big impact on traffic and there is generally a high value on their time (about $75/hour)

1) give trucks high priority to increase productivity and bypass congestion (big economic booster)

2) Segregate trucks from cars to allow more free-flow traffic between the modes

Design Characteristics of Truck Priority or Restriction Lanes

Truck only lanes are generally in the median, separated by a barrier or median. (Require special entrance and exit treatment). Truck lane restrictions force trucks to use only a subset of lanes (right two only).

Some impacts of Truck Priority or Restriction Lanes

Reduces truck delay and car delay, truck0only facilities can be designed more specifically for trucks (and paid for by them), Improves safety.