Carpool, HOV, Transit lanes Discussion View history

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Carpool lanes, High-occupancy Vehicle (HOV) lanes, and Transit lanes are road lanes reserved for vehicles meeting special requirements, either carrying at least a specific number of passengers more than the driver, or being a specific vehicle type. The number of required passengers in the vehicle can vary depending on the specific road.

Although currently Waze does not support the requirements of routing over these types of lanes, there are plans to add support for them in the future.

Supporting these lanes is a priority for Waze, and they are aware of the problems caused by such lanes.


Configuration and setting restrictions

These guidelines have been updated As of October 2014 to prepare for the upcoming HOV features. The old method was to map these lanes as Parking Lot Roads. This new method below should be used when mapping new lanes. There is no rush to redo existing lanes to make them compliant; do so only if you are working on them anyway, or are doing a general refresh in the area.

As an interim measure, these lanes should be added to the map as separate roads, with the road type set the same as the non-HOV lanes. However only the entrance ramps to these lanes should be set with the appropriate partial segment restrictions. The actual lanes themselves should not have any restrictions set on them, except for reversible lanes, or other restrictions which are in effect at all times on multi-use lanes as discussed below. This means that if you are not currently in one of these lanes the routing will avoid it, but if you choose to get into the lane, the routing will work correctly. Being that only the entrance to the lane is restricted, once you are already in the lane there will be no penalty for staying there, and you will be routed the fastest and most appropriate way to your destination. The caveat will be for multi-use lanes which will have restrictions set to force everyone who does not meet the lanes use criteria (at this time that will be everyone, since the client and routing server can only handle routes for private vehicles) out of the lanes before the enforcement period begins.

As of October 2014 the client and routing server are still unable to differentiate different vehicle types. Therefore all vehicles using Waze are treated as Private Vehicles, and any HOV restrictions will be applied to all vehicles. (This is the reason why the restrictions should ONLY be set for the on ramps, and not the entire length of the lanes on the segments themselves.)

This should only be applied to dedicated lanes that have exit and entry points.

Any time you are setting a road to allow HOV - 2, it must also be set to allow HOV - 3.

In the USA motorcycles are allowed to use HOV lanes, therefore when setting partial restrictions to only allow HOV - 2 (HOV -3), Motorcycles should also be allowed (unchecked). Some jurisdictions also Taxis and Buses to use the HOV lanes. These should be set accordingly in those jurisdictions.


There are special configurations needed for reversible, and multi-use lanes which change use criteria or direction at different times of the day.

Multi-use lanes

Lanes which only have the HOV restrictions in place for certain hours, and open to regular vehicles during other hours, need to have the restrictions on the entrance ramps set to only allow the specific vehicles for that road during the enforcement times, AND that same restriction must be set to only be in effect during the enforcement time.

The enforcement time should be expanded to start 15 minutes earlier, to account for drivers who experience traffic along their route prior, and prevent them from accidentally being routed onto the HOV lanes after the enforcement period begins.

These lanes will also require a similar restriction set on ALL the exit ramps, also with the enforcement period expanded to begin 15 minutes early. This will ensure that vehicles which do not meet the roads HOV criteria, but have been routed into these lanes prior to the enforcement period, will be routed out of these lanes before the enforcement begins. It is imperative that every exit ramp has these restrictions in place, otherwise instead of these vehicles being routed out of the lanes when the enforcement begins, they will all be funneled and routed to the one exit ramp which does not have these restrictions.

If when these lanes are open to the public (when the HOV restrictions are not in effect), they are still restricted to certain vehicle types (i.e. No Trucks), then that should be set as a separate restriction on the actual lanes to be in effect at all times.


Reversible lanes

These lanes should be set with separate time based partial restrictions restricting travel in each direction for the appropriate hours.

If the hours are adjacent to each other, meaning that there is no buffer time between the two travel direction of the lanes, then we will have to add a buffer time into to Waze for safety. In that case expand the restriction to start 15 minutes earlier so there is at least a 15 minute window when there travel is restricted in both directions between the open periods.


Example configurations

A multi-use lane which is open to the all vehicles during off-peak hours has to be set as a separate restriction from each of the enforcement periods.

Each of those restrictions must be set to the criteria restricted to only HOV - 2, HOV- 3, Motorcycles or Buses on weekdays during the hours of 6-10 am, and 3-8 pm.

Pointers for a complete solution

A complete solution needs to consider the following factors:

  • The driver would need to tell the Waze client app how many passengers are present in the car, or what vehicle type they are in for that trip. Waze would only offer routes over carpool lanes when they meet the criteria to be eligible
  • In some places, Electric or Plug-in Hybrid vehicles may also use HOV lanes, so this local situation must be known and the driver should be asked if the vehicle is allowed in HOV lanes for reasons other than number of passengers.
  • As car pool lanes are often adjacent to normal roads, GPS tracking is not always sufficient to differentiate between the two. For accurate road speeds Waze needs to assume you are using the car pool lane when you have passengers (and/or based on your speed). However if the lanes are separated even by a few meters, the server can usually tell the difference and the speed to the correct lanes, even if the client displays you as being on the wrong lane.
  • HOV lanes are being merged with Toll lanes (HOT lanes) and the user needs to be able to select if they want to allow toll roads. The map needs the ability to track multiple lane restrictions (HOV and/or Toll) for the same road rather than defining the road as either an HOV or a Toll lane.