A Change in California Might Prompt Other Places to Reconsider Their Approach to Traffic

Andrew Keatts | February 4, 2016 The state may shift from measuring congestion to measuring driving. That slight distinction makes a big difference.

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Andrew Keatts | February 4, 2016 The state may shift from measuring congestion to measuring driving. That slight distinction makes a big difference.

Andrew Keatts | @andy_keatts | February 4, 2016

Image via flickr/Neil Kremer Image via flickr/Neil Kremer

Saturday Night Live’s recurring skit, The Californians, combines two Sunshine State stereotypes. One is the Kardashian-esque lifestyle of self-absorbed affluence, complete with marital infidelity and copious drinking of white wine during the day. The other is Californians’ peculiar obsession with finding the perfect combination of freeway changes needed to shave a few minutes of commute time from their traffic-plagued existence.

But a proposed change in state regulations could slowly chip away at the latter characterization. And once fully implemented, it may spread to planning and transportation agencies across the country.

The change is simple, if subtle. The state will change how it measures the environmental effects of new housing, transportation and other development projects.

Projects will now have to focus on how much driving they create, rather than how much traffic they create in their immediate vicinity.

For example, a mid-rise development in an urban neighborhood will bring in new residents for its apartments and customers to its ground-floor restaurants and shops. Those residents and customers might worsen in traffic in the surrounding area.

Previously, that’s what state-mandated environmental reports on new projects studied, and its what city councils had to acknowledge to overcome objections of the project’s neighbors.

Now, though, those reviews ask a different question: will the project’s residents drive more or less than if the project weren’t built at all?

By being in an urban neighborhood, residents might be able to drive a bit less, by walking to bars, shops, and restaurants near their home, rather than driving, or having the chance to take transit to work. The project could, in essence, reduce overall driving even while it exacerbates nearby traffic.

The change is the state’s way of saying it wants to reduce driving – and the effect it has on air quality and the state’s carbon footprint.

To use planning jargon, the state is shifting from focusing on “Level of Service,” a measure of roadway congestion in a given area, to “Vehicle Miles Traveled,” or how many overall miles of driving a project creates (or reduces) for its users.

The change would happen when new projects are reviewed through the California Environmental Quality Act. It will likely make it easier to build homes in urban areas rather than new suburban subdivisions. And it could clear environmental roadblocks from things like transit projects, bike lanes and pedestrian improvements, according to the state’s proposal on the pending change.

“As a result, people will have better transportation options,” the document reads. “It also means that CEQA will no longer mandate roadways that focus on automobiles to the exclusion of every other transportation option. It will no longer mandate excessive, and expensive, roadway capacity.”

The proposed changes – which haven’t been enacted yet – stem from a 2013 law. The proposals are coming from the Governor's Office of Planning and Research and are open to the public to comment until October 10, at which point the decision will be made whether the make a formal change to state environmental law.

The changes could also make it easier in California to build projects within a half mile of a transit station. Any project that generates 15 percent fewer vehicle miles per person than the regional average would sail through its environmental reviews.

But the broad, philosophical change on how to measure a project’s effects isn’t just happening in California.

The federal government, through the Federal Highway Administration, recently told Streetsblog it was looking into ways it could encourage other governments to take the same leap as California.

Ron Milam, a transportation consultant in at the California firm Fehr & Peers, said a handful of governments beyond California are quietly considering a similar shift.

“There’s a continuing focus on climate change and greenhouse gas reductions, and as long as those variables are in play it’s going to garner some interest,” he said.

That governments are now focusing on how much driving a project creates, rather than how much congestion it creates, isn’t altogether surprising, said Roy Kienitz, a D.C.-based consultant at the Eno Center for Transportation and the former under secretary for policy at the U.S. Department of Transportation.

Like most major policy changes, he said, the shifting focus began with a handful of leading experts, and slowly made its way through the profession and is finally into government agencies.

“The (departments of transportation) in the middle of the country aren’t thinking of this,” he said. “It’s reaching out from the bleeding edge and into the cutting edge.”

What it Changes

A change from congestion to measuring the use of cars, Milam said, leads to entirely different conversations about how to build out a city.

When agencies measure traffic, developers and engineers try to change the road network to accommodate all the new drivers. They end up proposing widened roads, or additional turn lanes, to move all the new people through the same area without backing things up.

But if they measure car use, it leads to changes to the original project to make residents less car-dependent overall.

Developers instead build denser projects with a diversity of amenities on site — offices, retail, yoga studios — or they try to locate their projects near transit. The idea is to build a project so that it makes future residents less likely to use their cars.

“It more or less changes by 180 degrees what you do,” Milam said. “Now, it’s about working with a developer and a city or county to modify a project that will generate less car trips.”

Kienitz, though, said the shift might not make as big a difference as some experts expect.

Focusing on traffic delays typically leads to big projects like e road widenings, grade separations, and intersection modifications. But in recent years, tightening public budgets have already made those things more rare anyway, Kienitz said. The primary effect of a shift would likely be something communities are embracing anyway: fewer road-widening projects.

“You still see a lot of those project in fast-growing places like Texas and Arizona,” he said, “but how much of that work is getting done in California, anyway?”

He also said that, as Houston Mayor Sylvester Turner said this week, the fight over whether it makes sense to increase highway capacity to address congestion is mostly a settled issue; however, that’s less true when it comes to improving performance of key intersections in dense areas.

“Intersections are different,” Kienitz said. “I don’t think there’s a consensus that on a failing intersection, you shouldn’t do anything. That consensus exists with highways.”

Mostly, Kienitz said, improving congested intersections is an unsettled issue. And it’ll still be unsettled regardless of whether you measure it with auto use or traffic delays.

Improved Accuracy, if Nothing Else

One other advantage of the switch is that that it may be a more useful tool to understanding traffic, David Schrank, research scientist at the Texas A&M Transportation Institute, which authors an annual scorecard of traffic delay in major metro areas.

“Level of service” is typically expressed as a letter grade – a report card on how a stretch of road is performing. Vehicle miles traveled, meanwhile, is more direct. It measures how much someone drove yesterday, and how much they’re expected to drive tomorrow.

“If I tell you, your level of service went from D to C, you’d say, ‘Great, what’s that mean?” Schrank said. “Versus, if I tell you your daily driving decreased by 5 miles or whatever, that’s useful.”

One reason vehicle miles traveled is suddenly becoming more widely used metric for analysis, Schrank said, is that data collection is improving. Twenty years ago, we might not have been capable of relying only on VMT as a measurement tool, even if engineers had been willing to.

“This is evolving,” he said. “That’s not to say sometime in the future, with more data, we won’t change paths again.”

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