Thinking about Metro's HOV lane conversionsLost in the debate about Metro's rail plans has been their plan to convert the HOV lane network to a congestion-priced High-Occupancy Toll (HOT) lane network, where any vehicle can enter the lane that's willing to pay the price. The price is adjusted - either on a fixed schedule or in real-time - to keep the lane(s) free flowing. As regular readers of my blog know, I'm a huge supporter of this concept: MaX Lanes - Managed eXpress lanes that move the maximum number of vehicles at maximum speed.
The 4-managed lanes under construction down the middle of the new Katy freeway are getting national attention for the pioneering agreement between Metro, HCTRA, and TXDoT to reserve guaranteed capacity in the lanes for buses - up to 25%. Bob Poole at Reason calls these "Virtual Exclusive Busways" (VEBs), which pretty much exactly describes what they do: guarantee free-flowing lane capacity for buses or other transit vehicles, while using the rest of the capacity for cars, so no capacity goes to waste. The description of their VEB study is here, and the full pdf is here, with an appendix dedicated to the Houston case study, including the full text of the memo of understanding between the three agencies.
The Katy reconstruction, with the four new managed lanes, is under way as of this writing. Thus, Houston will be the nation's first metro area to implement a Virtual Exclusive Busway.As part of this conversion, Metro is looking at the possibility of converting single-lane reversible HOV lanes to two lanes of bi-directional HOT lanes (probably not barrier separated from the same-direction free lanes). This will give them a managed lane network in all directions all day long. The Katy Freeway is obviously a perfect example, with the Energy Corridor and Westchase jobs creating strong flows (and congestion) both directions all day long.
But I hope Metro thinks carefully before jumping to this model for all our spoke freeways. Many of them have strong single-direction flows: inbound in the mornings, and outbound in the evenings. Contra-flow buses are not going to have any speed problems, even in the normal free lanes. And, of course, how many people will be willing to pay to be in the managed lane(s) when the free lanes are freeflowing?
Instead, they may be more useful and bring in significantly higher revenue if they are configured as two or more single-direction reversible lanes, where capacity is maximized in the congested direction and people are willing to pay to get out of it. So, for example, 290 or 45 might have 3 or 4 free plus 2 or more managed lanes of capacity in the congested direction at rush hour, while the contra-flow direction would make do with just the 3 or 4 free lanes. It does keep some of the complexity of reversible lanes, but the reduction in wasted contra-flow capacity and the gain in in-demand capacity would be well worth it. And it would be safer, since it would keep the barrier separation from the slower congested traffic. Finally, it would help keep employers in a healthy core (downtown in particular) rather than the far suburbs, since the capacity will be focused that direction.