A common techno-utopian vision of the near-future city is one where automated vehicles come when called and whisk you to your destination, as you sit, relaxed and untroubled by traffic. But consider the opposite vision, that gridlock will be made worse by autonomous vehicles, which will spend much of their time driving around the city with no passengers. There is simply nothing about a vehicle being autonomous that makes it more likely to achieve higher occupancy. In fact, the current trajectory of AV deployment roadmaps and our transportation policy response ensures its average occupancy will be lower.
Car occupancy has always been pretty stable, with an average of 1.1 occupants at peak travel times. Outside of a limited number of areas where there are high-occupancy vehicles lanes or toll discounts, little effort has been made to incentivize a behavioral change. A small upward change of average vehicle occupancy (to, say, 1.2 or 1.3) would completely eradicate traffic congestion in our cities. Similarly, a small downward change (say 1.0 or 0.9) will be devastating.
Level 5 is the Wrong Destination
Today the dominant framework for understanding the development of AVs is what’s called the SAE Levels of Automation. It has been wholeheartedly adopted by everyone from auto companies to the highest levels of transportation authorities, including the U.S. Department of Transportation (USDOT). It is a staple of almost every presentation you will see on AVs. And level 5 autonomy is presented in our media as the pinnacle of disruptive mobility , as though we are more likely to carpool simply because a car is autonomous.
We already have a long-standing hierarchy with which to guide our transportation planning decisions. It prioritizes pedestrians and cyclists over transit, which it in turn prioritizes over cars. The SOV sits appropriately on the bottom rung. And yet now our traditional frameworks and rules are being bypassed in an attempt to accelerate the introduction of autonomous mobility. AVs are not discussed in relation to their level in a hierarchy. This risks diverting our focus from planning a smart, efficient transportation ecosystem.
A Crossroads for Transportation Authorities
All this is part of an understandable step toward enabling technological advancement, but it is a huge mistake to omit a strengthening of core transportation planning principles. While USDOT briefly acknowledges this risk in its voluntary guidance for state and local governments to “consider the potential for increased congestion, and how it might be managed,” it is negligent in applying traditional measures for mitigating this risk. Federally funded transit or vanpool projects, for example, are required to regularly submit NTD reports on performance, including vehicle occupancy.
Reinventing the Pyramid
And so we risk a transportation system that elevates AVs, including those with zero occupants, to the tippy-top of our planning hierarchy. AV manufacturers are accelerating toward this goal, as evident in our vehicle-centered connected infrastructure terminology such as “vehicle-to-everything” and a vehicle “green wave.” To avoid a likely negative impact on traffic congestion, transportation planners should commit to a renewed emphasis on occupancy-based planning for all modes, new and old – a re-affirmation, rather than an-upending, of the existing rules of the game.
Emmett Murphy is the chief product officer at Carma Technology Corporation.