More HOT lanes for Los Angeles?

According to the L.A. Times, the Los Angeles Metropolitan Transportation Authority has produced a study recommending further investigation into converting HOV (High Occupancy Vehicle) lanes on five sections of highway into HOT (High Occupancy and Toll) lanes.  

Demonstration projects for HOT lanes are being implemented already on two stretches of highway (14 miles of I-10 from Alameda Street to the 605 and on 11 miles of the 110 from Adams Boulevard to the Artesia Transit Center at 182nd Street).   

The philosophy is simple, it is about getting better use out of under-utilised HOV lanes.

For the uninitiated, HOV lanes are lanes set aside for vehicles with multiple occupants, otherwise known as carpool lanes or transit lanes.  The economics behind this being that it is a more efficient use of roadspace for a vehicle to carry 2 or more people than simply one, and if there were efficient road pricing, the value of time of occupants of such vehicles would tend to give them priority.   The problem with HOV lanes is that many HOV trips are opportunistic, in that people will do them anyway.  Couples, families and taxi trips are not car journeys undertaken by people who would otherwise have taken two cars in many cases.   Real carpooling remains very much a minority activity.

As a result, many HOV lanes have excess capacity which can be utilised if converted to HOT lanes.  Single occupancy vehicles can be tolled to use the lane (to ensure it remains free flowing) dynamically using DSRC (Dedicated Short Range Communications) technology, whereas multiple occupancy vehicles can still travel "free".

Let's be clear, congestion charging it is not, but it is pricing a lane for certain users, which is positive as it provides choice and comparison between what pricing can do and what "unpriced" lanes are.   By offering a free flow corridor it is an improvement, and provides a choice.

The interesting part of the LA experiment will be that lanes will be priced dynamically, so the price will go up as demand increases, so that free flow conditions are maintained. 

LA Streetsblog has looked at the official report which indicates that "Every corridor was rated on connectivity, constructability, transit benefits and revenue potential" which would appear to mean not only practicability of introducing free flow tolling on the lanes, but also some money could be made from it.

I wouldn't be surprised if there was some surplus revenue, taking into account operating costs and the capital costs of tolling in the first place.   However, the revenue will not be significant on this scale.   The real benefit is economic, in allowing existing road space to be better utilised it could form the basis for a wider network of such lanes. 

Of course the longer term question with HOT lanes is whether they are sustainable in the face of rising demand.   Tradeoffs will need to be made between increasing prices, tightening the HOV rules and providing additional capacity.  At what point will it be that higher prices are such that second people are carried in vehicles just to avoid the toll (so the HOV threshold should be raised to three), and ultimately when do such lanes end up having to be toll only (which by any measure of rational economics, they should be).

UPDATE:  San Gabriel Valley Tribune gives a lukewarm endorsement to toll lanes, but fears privately owned toll highways.  The question that could be asked is whether it would object to them if they were new roads.