Skip to content

Posts from the Traffic Category

Streetsblog USA
View Comments

Without Transit, American Cities Would Take Up 37 Percent More Space

Even if you never set foot on a bus or a train, chances are transit is saving you time and money. The most obvious reason is that transit keeps cars off the road, but the full explanation is both less intuitive and more profound: Transit shrinks distances between destinations, putting everything within closer reach.

A new study published by the Transportation Research Board quantifies the spatial impact of transit in new ways [PDF]. Without transit, the researchers found, American cities would take up 37 percent more space.

Transit-oriented development in Portland's Pearl District. Photo: Smartgrowth.org

Transit-oriented development in Portland’s Pearl District. Photo: Smartgrowth.org

The research team from New York, San Francisco, and Salt Lake City modeled not just how many driving miles are directly averted by people riding transit, but how the availability of transit affects the way we build cities.

By allowing urban areas to be built more compactly, the “land use effect” of transit reduces driving much more than the substitution of car trips with transit trips. Total miles driven in American cities would be 8 percent higher without the land use effect of transit, the researchers concluded, compared to 2 percent higher if you forced everyone who rides transit to drive.

On average, the study found, the land use effect of transit is four times greater than the “ridership effect,” or the substitution of car trips with transit trips. But the land use effect of transit varies a great deal across urban areas. In places like Greenville, South Carolina, it’s responsible for reducing driving 3 percent, the researchers estimate, while in San Francisco and New York City, it’s 18 percent and 19 percent, respectively.

Read more…

55 Comments

Why Is There So Much Traffic in NYC? It’s the Free Roads, Stupid

Since the de Blasio administration attempted to cap for-hire cars this summer, the debate over Manhattan traffic has gotten louder, but not more productive. Uber claimed it definitely wasn’t the problem. Some council members wondered if bike lanes were slowing down cars. Amid all the noise, something important got lost.

When roads are free, traffic is clogged. Photo: Kevin Coles/Flickr

When New York streets are free, New York streets are clogged. Photo: Kevin Coles/Flickr

At a hearing about Manhattan traffic this morning convened by Borough President Gale Brewer, a simple consensus emerged: The fundamental issue is the limited amount of street space in the Manhattan core and the practically unlimited demand to use it. Unless New York puts a price on roads, traffic congestion is going to remain intense.

“We can’t unsnarl our streets unless vehicles that take up the space on the street are charged a price. Otherwise, the space that we clear out today — by capping tour buses or Uber cars or 18-wheelers — will be filled tomorrow by other vehicle owners,” said transportation economist Charles Komanoff. “And the price needs to apply to all vehicles… based on the space that they take up. Because space is a finite resource.”

“The least efficient mode of transportation is the single-occupant car,” said “Gridlock” Sam Schwartz, who in addition to his Move New York toll reform proposal, backed the elimination of parking placards for most government employees. “There is no reason to be parking for free on the most valuable land possibly on Earth.”

Others proposed more aggressive ideas, like banning personal cars completely. “Private vehicles coming into Manhattan is insanity,” said Steve McLoughlin, an organizer with the International Association of Machinists and Aerospace Workers District 15, a union for black car drivers. “I don’t think that Manhattan can handle much more than the professional drivers, than the trucks that are necessary to supply our businesses, and the first responders.”

McLoughlin, who commutes from Monmouth County each day, backed Move New York toll reform as a step in the right direction for reducing congestion.

Uber also backed Move New York, which would include surcharges for taxi and for-hire vehicles below W. 110th and E. 96th streets. (The Metropolitan Taxicab Board of Trade, which represents medallion owners, backs the plan too.)

Read more…

Streetsblog USA
View Comments

Another Tall Tale About Congestion From the Texas Transportation Institute

Crossposted from City Observatory.

Everything is bigger in Texas — which must be why, for the past 30 years, the Texas Transportation Institute (TTI) has basically cornered the market for telling whoppers about the supposed toll that traffic congestion takes on the nation’s economy. Today, they’re back with a new report, “The Urban Mobility Scorecard,” which purports to measure congestion and its costs in U.S. cities.

The numbers (and from time to time, the methodology) change, but the story remains the same. Traffic is bad, traffic is costing Americans lots of money, and traffic is getting worse. Here’s the press release: “Traffic Gridlock Sets New Records for Traveler Misery: Action Needed to Reduce Traffic Congestion’s Impact on Drivers, Businesses and Local Economies.”

The trouble with TTI’s work is that, to put it bluntly, it’s simply wrong. For one, their core measure of congestion costs — the “travel time index” — only looks at how fast people can travel, and completely ignores how far they have to go. As a result, it makes sprawling cities with fast roads between far-flung destinations look good, while penalizing more compact cities where people actually spend less time — and money — traveling from place to place. These and other problems, discussed below, mean that the TTI report is not a useful guide to policy.

Read more…

Streetsblog USA
View Comments

FHWA Gleefully Reports That Driving Is Rising Again

Chart: Doug Short

Chart: Doug Short

After flatlining for nearly a decade, the mileage driven by Americans is rising once again. That means more traffic overwhelming city streets, slowing down buses, and spewing pollutants into the air. But to the Federal Highway Administration, it’s a development to report with barely contained glee.

This June, Americans drove 8.7 billion more miles than last June, according to FHWA, a 3.5 percent increase. Total mileage in 2015 is on pace for a new high — finally “beating the previous record” of 1.5 trillion vehicle miles set 2007, the agency reports, as if the further entrenchment of America’s car-dependence is some sort of achievement.

Low gas prices, population growth, and an expanding economy are three factors nudging traffic back onto an upward trajectory, not to mention a transportation policy regime that remains tilted overwhelmingly toward highway construction.

The recent growth in traffic, however, does not negate lasting signs of a long-term shift away from driving. Economist Doug Short gets into more detail about the nuances in the trends, pointing out that on a per-capita basis, Americans are now driving about as much as we did in 1997.

Read more…

13 Comments

Why Traffic Congestion Has Rebounded in the CBD

Traffic congestion in the Manhattan core is rebounding. Travel-speed data culled from taxicab GPS and released last month by City transportation and taxi officials suggest that average motor vehicle travel speeds in the Central Business District fell by 8.5 percent from 2012 to 2014. The slowdown follows years of flat or even rising speeds — a phenomenon that predated the 2008 financial collapse and undermined congestion pricing proposals by making car, bus, truck and taxi travel in the heart of the city a little more efficient and predictable.

The speed data were issued during the recent Uber controversy, but they bear on a host of other policy issues including Vision Zero, cycle infrastructure, and bus priority signals and lanes. To inject some rigor into these discussions, I’ve created a special section of my Balanced Transportation Analyzer spreadsheet to approximate various factors’ roles in re-congesting the CBD. My preliminary findings are summarized in the graphic. (Readers interested in a deep dive should download the BTA and navigate to the new tab, CBD Congestion.)

Table of Congestion Causation _ 28 July 2015

Graph: Screen shot from the Balanced Transportation Analyzer

The task is to account for an “adjusted” 10.5 percent drop in CBD travel speeds. That figure tacks 2 percentage points on top of the observed 8.5 percent reduction to reflect the fact that the 20,000 a day decrease in motor vehicle entries from 2012 to 2014 also reported by DOT should have increased CBD travel speeds by 2.0 percent. Here are details:

Read more…

28 Comments

Hey Brian Lehrer — Traffic Congestion Is Not a Vision Zero Tactic

This morning on WNYC Brian Lehrer said he didn’t understand why Mayor de Blasio would want to penalize Uber for making traffic congestion worse, since the mayor is “causing congestion purposely” to make streets safer for walking and biking.

The speed limit is not why this is happening. Photo: @BrooklynSpoke

The speed limit is not why this is happening. Photo: @BrooklynSpoke

Here’s an excerpt:

They want to make driving in the city as unpalatable as possible so people switch to mass transit, which is more in the public interest for a host of reasons. And I tend to support that, that’s a good idea. Also the de Blasio administration has made Vision Zero a central policy — something else I support. But again the goal is to make traffic go slower, not to make it easier on cars. They’ve reduced the official speed limit too. And congestion accomplishes the same goal — that is, fewer pedestrian fatalities — by other means. Traffic means less speed, which means more pedestrian safety.

Like a lot of people who weighed in during the Uber debate, Lehrer confuses speed limits and average speeds.

Lowering the maximum speed people are allowed to drive has nothing to do with a grinding crush of cars inching along at a few miles per hour. An easy way to grasp the difference: The citywide speed limit is 25 miles per hour, while last year the average speed in the Manhattan core was 8.51 mph. Congestion is a symptom of too many motorists trying to use scarce street space at the same time, not a tactic to make drivers travel at a safe speed.

Put another way, in the early 1980s motor vehicle traffic was moving at an average speed of 9.8 mph on midtown avenues and 6.4 mph on crosstown streets. Though congestion was about the same as it is now, more than twice as many people were dying in traffic.

Lehrer also said taking cars out of Central Park was de Blasio’s way of creating congestion on the avenues. Instead of propagating tabloid-worthy conspiracy theories, we liked it better when Lehrer was calling for “bike lanes everywhere, separated from traffic.”

16 Comments

The Real Reason Uber Traffic Matters in NYC

concourse_redesign

Where traffic is worse, the politics of turning a wide, car-centric street into a safe, efficient street are tougher. Rendering by the Street Plans Collaborative and Carly Clark via Transportation Alternatives

For a moment yesterday, it seemed like the big clash between the taxi medallion industry and app-based car services, framed in terms of Uber’s effect on snarled Manhattan traffic, might veer into unexpectedly brilliant territory. There was Deputy Mayor Anthony Shorris in the Daily News, telling the MTA that City Hall would consider the Move NY traffic reduction plan to fund transit investment. Finally, a sign that some of the big players are getting serious about a comprehensive fix for the city’s congestion problem.

But the moment didn’t last long, with Governor Cuomo extinguishing the road pricing talk right away. Soon after, Mayor de Blasio beat a sudden retreat from his proposed cap on for-hire vehicle licenses, getting a few concessions from Uber, and now the whole episode will fade from the news cycle, at least for the time being.

The Uber fight was a rare case where transportation issues became front-page news, but the arguments about streets and traffic tended to descend into stupid talking points really fast. Uber NYC General Manager Josh Mohrer was hardly the only person who tried to blame bike lanes and other safety measures for the recent downturn in average Manhattan traffic speeds. Council Member Dan Garodnick, someone who generally gets how streets work and chooses his words carefully, was the first public figure on record to toss around that theory.

When you’re talking about the downsides of congestion, it’s tough to avoid framing the problem like an old-school traffic engineer, placing paramount importance on the movement of cars. Even on Streetsblog, we’ve run plenty of posts talking about the effect of Uber in terms of average traffic speeds. The trouble is that when you focus on how easily people can drive around the city, you create an opening for people to point their finger at anything that might slow down cars — like bike lanes, or a lower speed limit.

You can try to reason with these people and explain the difference between peak speed and average speed, or show the data about bike lane redesigns that had no discernible effect on traffic. And that might win some arguments. But if you want streets where bus riders have swift trips, where people of all ages feel safe walking and biking, you’re going to have to make some changes that — at least for a while, before a new equilibrium sets in — slow down cars.

We need to come at the problem from a different angle. So how about this: Traffic congestion in New York is terrible because it’s an obstacle to designing streets that work best for our city.

Read more…

28 Comments

Uber’s Own Numbers Show It’s Making Traffic Worse

Uber blasted out an Excel spreadsheet to reporters this morning, accompanied by a story and editorial in the Daily News, with data providing a snapshot of how many Uber vehicles are on Manhattan streets south of 59th Street, New York’s central business district. While Uber claims the data shows its vehicles aren’t responsible for congestion in the city core, transportation analyst Charles Komanoff has crunched Uber’s own numbers and estimates that the service has actually reduced traffic speeds in the central business district by about 8 percent.

Photo: Wikipedia

Uber’s data dump [XLS] released hourly information on the number of pickups and drivers below 59th Street and in the rest of the city between May 31 and July 19. It used that data to calculate the number of Uber vehicles in the central business district, where half of the company’s trips originate. Between 7 a.m. and 7 p.m., there were an average of 1,904 Uber cars on the road below 59th Street.

That seems like a small number at first glance, and Uber highlights that fact by proclaiming it “is not the source of Manhattan congestion.” But the question isn’t whether Uber is the root cause of all congestion — it’s whether Uber is making the current traffic situation worse.

So how do 1,904 for-hire cars circulating the congested Manhattan core actually affect traffic? To answer the question, Streetsblog turned to Komanoff, whose “Balanced Transportation Analyzer” [XLS] models the impact of toll proposals and other changes to city traffic. Uber’s data release provides more detailed information than what was previously available to the public.

The volume of Ubers is similar to the 2,000 yellow taxi medallions the Bloomberg administration proposed to auction off in 2012, which Komanoff calculated would make average traffic speeds 12 percent worse. To understand what happens to Manhattan traffic with 1,900 Ubers in the mix, Komanoff adjusted his model in a couple of key ways to account for the fact that each Uber vehicle likely affects Manhattan traffic less than each yellow cab.

Read more…

10 Comments

Uber and Manhattan Gridlock Are Rising Together

How responsible is Uber for the 9 percent drop in Manhattan travel speeds that New York City transportation officials reported last month? The answer appears to be: quite a lot. 

Photo: Wikipedia

If — and it’s a big if — the surge in use of Uber and other app-based car services is not offset by a decline in use of yellow cabs and private autos, then three-quarters of the speed reduction can be laid at the feet of Uber, Lyft, et al. That’s according to my “Balanced Transportation Analyzer” (BTA) traffic model that calculates benefits from toll plans like Move NY, but can also assess the impact of almost any traffic-related change in NYC, especially Manhattan.

The finding about Uber’s traffic impact runs counter to the Daily News’ bald assertion in an editorial last Sunday: “From a traffic perspective, a few thousand new cars in Midtown and downtown (where 72 percent of the app cars make pickups) is a tablespoon in a lake.” 

The News would be right if we were only talking about another two or three thousand private autos joining the three-quarters of a million motor vehicles that are driven daily to or through Manhattan’s Central Business District, which would worsen CBD traffic speeds by a minuscule 0.2 percent, according to the BTA. But as the News itself pointed out, Uber now commands some 19,500 cars in the city, a figure that is growing by up to 2,000 a month. Compounding this, each Uber vehicle racks up five to six times as many CBD miles as one private car.

Even allowing that a third of Uber cars are inactive on a typical day, according to the News, that still means the remaining two-thirds are traveling approximately 190,000 miles daily in Manhattan south of 60th Street. (This assumes the average Uber trip consists of two miles with the passenger and half a mile without.) These miles are enough to add 5.7 percent to the 3,385,000 daily CBD “baseline” miles covered by cars, cabs, trucks and buses.

It would take an awful lot of private cars to gum up CBD traffic to the same extent. Indeed, based on my estimate that a typical auto driven into the Manhattan core covers about 2.7 miles before leaving the area, the extra number required would be 72,000 a day. When that number of additional daily cars is run through the BTA, the result is a projected 6.7 percent slowing of vehicular travel averaged across the entire Central Business District.

Read more…

55 Comments

Team de Blasio Makes Its Case for a One-Year “Uber Cap”

The scene at today's transportation committee hearing. Photo: Stephen Miller

The scene at today’s transportation committee hearing. Photo: Stephen Miller

The de Blasio administration made its case for temporarily restricting the growth of licenses for ride-hailing services like Uber at a City Council hearing this morning. With congestion in Manhattan getting worse, City Hall’s plan is to cap the number of new for-hire vehicles on city streets for the next year while it studies the impact of the industry on traffic.

Today, the city splits most car services into two categories: medallion yellow taxis and for-hire vehicles (FHVs), which include green boro taxis, livery services, limousines, and drivers for companies like Uber and Lyft. Each has different rules and regulations.

Yellow cabs, which are the only service subject to a surcharge that helps fund the MTA, are limited by the number of medallions. The number of boro taxis, which are supposed to pick up passengers outside the central areas of the city, is capped by state law. But the city has no mechanism to limit the number of black cars, hence City Hall’s need for legislation introduced in the City Council by Transportation Committee Chair Ydanis Rodriguez and Steve Levin.

Since the advent of Uber and other app-based services, the number of FHVs on city streets has boomed, growing 63 percent since 2011. Nearly three-quarters of trips made by the new FHVs originate in Manhattan south of 60th Street, according to DOT, and the city is worried that these trips are a major factor behind the recent increase in congestion in the center of the city, which in turn may explain why bus ridership is dropping faster in Manhattan than in the outer boroughs.

“This decrease in traffic speeds is happening at the same time that overall traffic into the Manhattan CBD has fallen,” said Transportation Commissioner Polly Trottenberg. While traffic in 2014 was 9 percent slower in the Manhattan central business district than it was in 2010, the number of vehicles entering the CBD each day had dropped 6 percent over the same period. The implication: The spike in for-hire cars circulating Manhattan has more than offset the reduction in other vehicles driving into the city center.

Read more…