Houston's new mayor, Sylvester Turner, recently called for the Texas Transportation Commission to re-think its approach to mobility in large cities like Houston, saying – in essence – that it's time to shift focus from vehicles carrying only one person to other ways of getting around. Freeway widenings are reaching their limits and congestion is still increasing. Wisely, he left open to discussion what exactly that new approach might look like. How can Houston be similarly thoughtful in its approach going forward?

The first step is learning from what has and hasn't worked for other cities. Rail investments in other decentralized, Sunbelt cities, such as Los Angeles, Dallas, Denver, and Atlanta, have been disappointing. Los Angeles in particular is a cautionary case. With $9 billion spent on new rail lines in a city with twice the density of Houston and perfect walking weather year-round (unlike our summers!), they have seen overall declines in transit ridership and worsening traffic congestion. Rail is incredibly expensive — typically over $100 million per mile — and just not well suited for spread-out Sunbelt cities built around the automobile in the post-WWII era.

The second step is understanding the ramifications of coming new technologies — specifically self-driving cars. While the general vehicle fleet will take decades to turn over as people slowly replace their cars, we can expect extremely rapid adoption among taxi services as soon as these vehicles are available in the early 2020s. The economics are simply too compelling: Almost 80 percent of the cost of a ride is the driver. One estimate has the typical ride dropping to $3.25, with shared rides going for $2.43 or even as low as $1 with SUVs carrying up to six passengers at once along a shared route.

Customized SUVs could be made with private individual compartments, so that passengers traveling in generally the same direction could share a ride without interacting. When vehicle pulls up, an indicator could tell you which door to enter for your compartment, then alert you again when it's time for you to get out based on the destination you put into your smart phone. A private ride combined with shared prices and efficiency: the best of both worlds.

The impact on traffic congestion could be dramatic, as fewer vehicles carry more riders. Analysis by MIT, Stanford, and others estimate that shared rides could reduce the number of vehicles needed to carry the same number of trips by 70 to 90 percent. Quite the silver bullet to reduce traffic congestion! Then there's the icing on the cake: Automated drivers are expected to dramatically reduce crash injuries and space required for parking, which will free up a tremendous amount of much-needed land in our cities.

All indications are that these super-cheap, point-to-point autonomous taxi services will essentially replace most bus and rail transit: Most trips would be much faster and more direct at nearly the same cost. In fact, transit agencies like METRO may switch their fleets to such vehicles, providing better service to their customers. Helsinki's transit agency is already a pioneer of this transition, offering on-demand mini-vans available via smart phone app.

In this new era, rail will only make sense in the very densest cities in the world, like New York and Tokyo. And cities investing billions in rail projects now may find themselves with substantial white elephants on their hands in the near future — a fate Houston should definitely try to avoid.

So if freeways are reaching their limits, and traditional rail and bus transit face obsolescence, what's the right answer for Houston right now?

Consider Managed eXpress Lanes — MaX Lanes, for short — which aim to move the maximum number of people at maximum speed (a phrase recently adopted by TxDOT's Houston office). These lanes are the next generation of METRO's very successful HOV lanes: lanes that are restricted to high-occupancy vehicles, such as buses, carpool vans and cars carrying more than one person. HOV lanes are much less crowded than regular lanes, so — as Houston commuters know well — their traffic usually moves far faster.

If we create a comprehensive, connected, two-way network of these freeway lanes across the metro area — including our loop freeways, like 610 and Beltway 8 — then multi-occupant vehicles (self-driving or not) can offer fast, nonstop, point-to-point service between any neighborhood and any job center.

The lanes will transition naturally to self-driving vehicles. When the technology is mature, these lanes can be reserved exclusively for auto-piloted vehicles, instantly increasing the lanes' capacity two to four times as the cars flow more smoothly, closer together and with less braking.

MaX Lanes are also perfect for serving a spread-out city of multiple job centers (fewer than than seven percent of Houston's jobs are downtown). If the mayor is serious about shifting trips with more than one occupant in the vehicle — aiming to go from 3 percent to 15 percent and beyond — MaX Lanes are best strategy to reach that goal.

In his address to the Transportation Commission, Turner also called for greater inter-agency cooperation. MaX Lanes are the perfect application of such cooperation, with a single vision bringing the city together with TxDOT, HCTRA, and METRO. The lanes give the mayor an opportunity to be the leader who sets the stage for the next era of Houston's growth.

Tory Gattis is a Founding Senior Fellow at the Center for Opportunity Urbanism and writes the Houston Strategies blog.

Bookmark Gray Matters. Quite the silver bullet to reduce traffic congestion!