Tag Archives: The 405

Freeway Ramps and Crosswalks

We haven’t had a freeway post in a long time, but a while back we talked about short-term improvements that can improve the interface between freeways and city streets for pedestrians and bicyclists. The principle goal is to reset drivers’ minds for the urban environment by forcing them to slow down or stop when exiting the freeway, so that they don’t hit city streets at freeway speeds. The best designs for this are the tight diamond and the tight four-ramp partial cloverleaf.

Ideally, we’d like to also strengthen pedestrian connections by providing crosswalks on the city street that would run concurrent with the freeway off-ramp. The city street is often a major arterial road where the crosswalk spacing is too large, and a crosswalk at the ramp would help alleviate that problem.


Here are two locations where such crosswalks were actually installed.

First, the 134 and Glendale Ave:

Second, the 134 and Pacific St:

Nice work, Glendale, on getting those tight diamonds, tight four-ramp partial cloverleaves, and extra crosswalks!

However, freeway ramps are not great locations for crosswalks. At most intersections, the majority of traffic goes straight, with smaller turning volumes, making it feasible to have concurrent pedestrian movements without much danger to pedestrians or impact to traffic capacity. At freeway ramps, though, the situation is reversed. Almost all traffic is turning, so concurrent pedestrian movements create danger to pedestrians and significantly reduce traffic capacity. While pedestrian safety can be improved at such intersections with a leading pedestrian interval, the other problems remain.

Fortunately, there’s a way around this issue that improves pedestrian connections, has a low impact on traffic capacity, and serves the goal of forcing drivers to adjust to city driving conditions. We can simply move the ramp crosswalks away from the freeway, and synchronize the traffic lights so that the crosswalk movement is concurrent with the ramps.


This creates space for the traffic exiting the freeway to queue up. Since drivers exiting the freeway will always encounter a red light at the crosswalk, they will be forced to stop and reset their minds. Pedestrians do not have to contend with conflicting traffic, and the location of the crosswalk might better serve them. A crosswalk adjacent to a freeway will be located such that the freeway is occupying much of the nearby street frontage, whereas a crosswalk further away will serve more development.

If there’s an unsignalled minor street nearby, that’s a natural location for a new traffic signal and the crosswalk. Let’s look at a few examples around the county.

The 134 & Pacific in Glendale:


The 10 & Normandie in LA:


The 405 & Artesia in Torrance:


The 405 & Western in Torrance/LA:


These improvements obviously require new traffic signals, which is a considerable expense. Therefore, they should be rolled into either freeway improvement projects or arterial corridor improvements. The pedestrian signal is only a simple two-phase signal, and doesn’t need much intelligence since it will be synchronized with the ramp, which will help some with costs, especially if part of a larger job.

Westside Traffic, Peak Period Edition

A commenter on this post on Westside traffic asked if peak hour data might show different patterns, so I created similar graphics for the same roadways using the same data (Caltrans publishes peak hour, peak month, and yearly average traffic).

I’ll let the graphics speak for themselves. The peak hour patterns are quite similar to the total volume patterns, including the structural changes on the 405 and Venice coinciding with completion of the freeway widening project between the 90 and the 10. It’s actually a little surprising to see so much of a change in peak hour volumes – I would have guessed that changes in total volumes would be reflected in a shorter peak, leaving the peak hour itself relatively unchanged, rather than a more uniform change. These facilities are all near capacity, so if more cars enter the systems, peak volumes can only go up so much, and the increase would be expressed as a longer peak period and greater total delay.

I’ve put the daily volumes & peak volumes side by side so you can easily compare. Note that the y-scales are necessarily quite different. As always, click to embiggen.

Venice-both the405-both the10-both SM-both Lincoln-both

Is Westside Traffic Really Getting Worse?

Recently, the LA Times has published some articles positing that as freeway traffic gets worse, people have started using smart phone apps like Waze to try to avoid it, causing worsening congestion on neighborhood streets. The problem is that you can’t trust people’s perceptions of traffic. Traffic, like behavior of teenagers, is almost always perceived to be getting worse, data be damned.

Since Caltrans publishes freeway traffic counts going back to 2002, we can take a look at the evolution of Westside freeway traffic leading up to the last economic peak, the crash, and the current period of growth. Here’s a plot of traffic on the 10 between Lincoln and Vermont, from 2002 to 2013.

How to read: traffic volume is the vertical component. Time represented on the diagonal from top left to bottom right. The location on the freeway is represented west to east on the diagonal from bottom left to top right. So, if you follow a diagonal line from bottom left to top right, you’re seeing traffic volume on the freeway build as you head towards downtown. If you follow a diagonal line from top left to bottom right, you’re seeing how traffic has changed over time at a particular point on the freeway.

For example, following the diagonal for 2013, we can see that traffic is below 250,000 vehicles per day from Overland west, and above 250,000 vehicles per day from National east (where the line leaves the green area and enters the yellow band). Following the diagonal for Vermont, we can see that traffic volumes were above 325,000 at Vermont from 2002 to 2006, then between 300,000 and 325,000 from 2007 to 2011, and then back above 325,000 from 2012 to 2013.

If these graphics don’t make sense, there are some simpler line graphs at the bottom of the post showing the same freeways for years 2002, 2007, and 2013.


What can we see? Traffic declined across the whole freeway from Santa Monica to downtown LA as a result of the recession. West of La Brea, traffic volumes have not recovered or have declined even further, though east of there, traffic has started to recover. No boom in traffic on the Westside on the 10.

Here’s the 405 between the 90 and Mulholland (Sepulveda Pass). Information is the same, but the rotation is a little different to better show different patterns. I left the interchange with the 10 off the plot because it made a large, confusing dip between Olympic and Santa Monica.


From Wilshire to Sepulveda Pass, traffic volumes on the 405 haven’t increased noticeably either. There has, however, been a large increase in traffic between the 90 and Santa Monica since 2007. This correlates to both the economic recovery and the project that widened the freeway between the 90 and the 10 (induced/latent demand is real!).

Since some Westside arterials are still Caltrans-numbered routes (Lincoln, Santa Monica, and Venice) we can also look at trends on those facilities. Here’s Lincoln from the 90 to the 10.


From the 90 to Washington, traffic volumes fell in the recession and have not yet recovered to previous peaks. The stunning thing here is the drop of 10,000+ vehicles per day between Venice and the 10 freeway. It seems possible that the completion of the widening project on the 405 shifted some traffic from Lincoln to the freeway.

Further evidence for that conjecture comes from Venice between Lincoln and La Cienega.


Roughly coinciding with completion of the freeway project, Venice saw a considerable increase in traffic in the vicinity of the freeway and points east.

Lastly, here’s Santa Monica.


Nothing really jumps out here. Traffic declined during the recession, and consistent with national experience, has not recovered to previous peaks.

There’s no clear pattern of increasing traffic on these roads, but that doesn’t necessarily mean the story about worsening traffic on side streets is wrong. Technology like Google Maps and Waze makes information about the road network more accessible, and it’s certainly possible freeway and arterial traffic growth has been muted by people using the side streets. The city’s traffic data is also available through the Navigate LA website; maybe some enterprising person with programming skills can figure out a way to pull it out! Either way, it’s apparent there have been some shifts in traffic patterns, which we’d expect to make congestion worse in some places.

Note: 2009 data was missing, so I made it the average of 2008 and 2010.

the10-line the405-line Lincoln-line Venice-line SM-line

Sepulveda/LAX Transit Part 4: Arrested Arterials, Arrested Development

Los Angeles has a great arterial grid. Almost.

As Jarrett Walker says, grids are great for transit, because they let you efficiently serve a large geographic area with high-frequency service, while avoiding the problems of branching. In that post, Walker calls Los Angeles and Vancouver “two of the most perfect transit cities I’ve ever seen, in their underlying geography.”

Well, almost.

Aside from the obvious topographical barriers like the Santa Monica Mountains, there’s a weakness in LA’s arterial grid: on the Westside, practically nothing west of La Cienega is worthy of being called a north-south arterial. East-west movement is another story, an embarrassment of riches: Pico, Olympic, Santa Monica, Wilshire, and Venice. There’s not one north-south arterial that’s as good as any of those east-west boulevards. This is part of why the 405 is so horrendous and traffic on the Westside in general, the largest bugaboo of Westside NIMBYs, is terrible. Most importantly, it has significant implications for what high quality north-south transit on the Westside will look like.

Let’s take a closer look. The map below shows how many lanes each Westside arterial has in each direction. It also shows peak-hour only lanes (created by parking restrictions) with dashed lines. I realize many readers may not be particularly worried about auto capacity, but the number of traffic lanes is a reasonable proxy for both the technical and political challenges to creating a dedicated right-of-way (ROW) for transit.


How Did We Get Here? Or, A Boulevard for Our Kingdom

It wasn’t supposed to be this way.

Believe it or not, parts of the Westside were undeveloped as recently as the end of World War 2. Older urban nodes, like Palms, Santa Monica, Westwood, Venice, and Beverly Hills, were scattered among farmers’ fields and country clubs. After the war, with construction of the 405 and UCLA, the areas in between these nodes rapidly developed as single-family neighborhoods. Partly due to preexisting development, and partly due to poor planning foresight, adequate ROWs for north-south arterials were not reserved. (Note that this mistake is rarely repeated nowadays; suburban sprawl is planned with ridiculously wide ROWs saved for arterial roads.)

Despite having been developed with single-family residences (SFRs), at that time much of the Westside was zoned for multiple-family development. As discussed previously, by the 1950s, low-rise apartments known as dingbats were popping up in the more established neighborhoods, such as Palms, and in the area near UCLA.

By the early 1960s, high-rise residential towers were sprouting up along Wilshire Blvd, as detailed in the city’s 1963 Westwood Economic Study. By the city’s generous standard of high-rise (4+ stories), there were 19 buildings in this class completed or under construction. The study noted that “rents in the newer high-density apartments [were] considerably higher”. The average monthly rental for a one-bedroom in a high-rise in 1963 was $2,370/month; compare this to one-bedroom dingbat apartments in Oakland, renting for $820/month at the same time, or in Palms, renting for $610-$820/month in 1970. (All values 2014 dollars.)

However, the study went on to note that there was no reason to worry about these expensive rentals, because “increasing demand for apartments on the part of the lower-middle and low income groups. . . can be satisfied in part by the older portions of the existing housing supply, and in part through new smaller apartment structures which could be built at lower cost. Such structures are being built in quantity throughout the city and metropolitan area. . .” Yep, you know who that is.

The rapid changes on the Westside came with growing pains. For example, the Palms-Mar Vista-Del Rey Socioeconomic Study (1970) found that population increased from 19,399 in 1940 to 78,134 by 1956, after which time further growth required replacement of SFRs, some scarcely more than a decade old, with multi-family developments. In 1950, Palms-Mar Vista had 2,361 apartments and 11,859 SFRs; by 1970, 15,883 apartments and 13,100 SFRs, with the number of SFRs having peaked in 1960 and by then declining as they were replaced by apartments.

Probably the biggest change, though, was Century City bursting onto the scene in 1963, rising from a former Fox studio backlot. Along with continued growth at UCLA, Westwood, and Santa Monica, the Westside was becoming one of the most important business districts in Los Angeles. The Westside’s boom strained the area’s underpowered road and transit network, resulting in worsening traffic congestion. In particular, Century City is poorly located and laid out with respect to north-south traffic movement. (Perhaps its developers quite logically expected redevelopment of adjacent golf courses, allowing Avenue of the Stars to be extended north and south.)

The city did not sit idle in the face of this congestion. While the need for rapid transit along the Wilshire Corridor was already well-recognized by the early 1970s, the plans drawn up for north-south movement reflected that auto-centric era. City traffic engineers proposed widening many north-south roadways, including every one shown on the map above between La Cienega and Lincoln (except Sepulveda, which presumably was already an arterial). These plans were backed by City Councilman Louis Nowell, a notoriously pro-growth politician who, in addition to greater urban density, also supported questionable amenities like the Laurel Canyon and Beverly Hills Freeways, and oil drilling in Pacific Palisades.

Westside SFR owners, having bought into the suburban dream only to find themselves in the midst of a booming metropolis, understandably did not share Nowell’s vision. By November 1972, the LA Times reported that opponents of density and street widening, dubbed “environmentalists”, had succeeded in getting the city to cancel plans for Castle Heights-Beverwil and Motor in the West LA plan area. The West LA plan was approved in December 1973. Further west, the Times reported that by early 1974, Mar Vista residents were protesting street widening in their neighborhood. By December 1974, city planners had relented, only proposing to widen Bundy-Inglewood and Barrington-McLaughlin-Slauson. Unsatisfied, voters elected a slate of “environmentalist” candidates to the city council, which proceeded to eliminate all north-south improvements save Centinela in early 1975.

Nowell complained bitterly, arguing that the West LA Plan would “[turn] this city back into a bike and horse economy, like some cruddy little town” and predicting that the Palms-Mar Vista-Del Rey Plan would turn LA into a “cow town because you can’t get around”. The city traffic engineer warned that “if people think traffic in the area is bad now, they ain’t seen nothing yet”. City Councilor Marvin Braude, one of the “environmentalist” councilors, argued that they had shifted the planning process on the Westside “to such things as car pools and rapid transit”, a claim that the last 40 years of history has proven dubious under the most generous definition of the word. Other opponents of development posited more metaphysical arguments, such as “suppose they widened the streets and no cars came”.

Ultimately, widening was restricted to Robertson, Overland, and Bundy-Centinela, though vestiges of the planned wider roads can still be found from Beverwil to Barrington. This requires the city to try to coerce Century City traffic into traveling over a mile east or west before heading south to access the 10.

Opponents of development also secured significant downzonings with the West LA Plan and Palms-Mar Vista-Del Rey Plan. The latter plan, calling for preservation of SFRs, restricted zoning for apartments to areas where they were already being developed, primarily the area of Palms east of Overland with a few tendrils extending to the west. This was expected to reduce the population at build-out from 168,000 to 130,000. (Unfortunately, the articles don’t say how many units this represented; obviously, regional prices and rents will have an impact on household size, and consequently on population.)

The West LA Plan likewise downzoned areas that had been zoned for multi-family development, and expected to reduce population at build-out from 135,000 to 106,000. Around the same time, the permissible density of Century City was reduced, including a reduction in commercial space as well as slashing the number of residential units allowed from 8,000 to 4,000. The density allowed on Wilshire Blvd was also reduced.

By 1975, a new plan was in place for the Westside, one that envisioned a future of lower density and less traffic, but would only deliver on one of those promises.

Fast Forward to Today

There would be further challenges to urban density in the intervening years. For example, the Braude and Zev Yaroslavsky-backed Prop U (1986), reduced allowable FAR in most of the city’s commercial zones from 3 to 1.5. While Prop U targeted commercial development, C1 & C2 zones allow R3 & R4 uses by default, so Prop U effectively reduces residential development opportunity as well.

Century City commuters stubbornly refused to use Overland and Robertson, leading to further resident outcry over “cut through” traffic. But despite the promises of shifting planning away from the automobile, rapid transit and pedestrian/bicycle plans have also been stymied since that time. Plans for a subway on Wilshire were delayed for years by Henry Waxman’s 1985 ban on federal funds for subway construction on the Westside, and Zev Yaroslavsky’s 1998 ballot measure that precluded use of Measure A and Measure C funds for such purposes. The Expo Line will open soon, but only after overcoming several lawsuits from Cheviot Hills and Rancho Park residents. Westside streets remain auto-oriented, with some lacking sidewalks, and bike lanes being opposed by resident groups like the Westwood South of Santa Monica Homeowners’ Association.

Where Do We Go From Here? Or, Our Kingdom for a Boulevard

It should be clear that, in the modern framework of thinking about cities, there are no clean heroes or villains in this story. On one side, you had support for greater urban density, to be enabled by widening streets all over the place and hacking the Laurel Canyon, Beverly Hills, and Slauson Freeways into existence. On the other side, you had strong “environmentalist” support for eternal SFR neighborhoods without any meaningful support for rapid transit, resulting in innumerable hours of traffic misery for people forced to commute on the 10 and the 405.

For our purpose here – north-south transit on the Westside – we need to understand this history, and how it affects the transit options that are available. Congestion and the uneven street grid make it difficult to lay out effective, efficient transit lines on surface routes, but the low density neighborhoods call the practicality of fully grade-separated transit into question. From a transit perspective, the two biggest gaps in the arterial network are probably the lack of a direct north-south connection from Century City to points south, and the incomplete Barrington-McLaughlin-Slauson arterial. The former makes it difficult to plan any north-south transit service to Century City, including connection to the Expo Line, the only high-quality rapid transit service in the near term. The latter would allow for a nice surface BRT route from the Slauson Corridor to West LA along roads with no ramps to the 10 or the 405, avoiding the congestion caused by such facilities.

This post is not to say that all these street widening projects should be resurrected. US cities seem to be unusually adept at destroying themselves that way, though other cities since the time of Haussmann have shown you can have wide boulevards that are an urban amenity, and arterials that will hopefully have high-quality transit someday, like La Cienega, came into existence that way. The takeaway here is that the north-south roads, as they exist today, are the reality we have to work with, and they are going to make it difficult to get exclusive or semi-exclusive ROW. It’d be convenient if we had an Olympic Blvd, but we don’t. More on the potential north-south transit services next time.

For opponents of development on the Westside, the question is more philosophical, and I’d put it like this: you’ve been tilting at the windmills of traffic and density for 50 years now. But no neighborhood is an island. Century City can’t be unbuilt. UCLA and LAX aren’t going anywhere. Santa Monica, Venice, and Playa Vista are some of the hottest commercial markets in the region. People living in the Valley and South Bay are always going to have reasons to travel to the Westside; service industry workers are always going to need a place to live and a way to get to work. How much longer are you going to keep fighting a battle that can’t be won the way you’re fighting it?


Westwood Economic Study, City of Los Angeles (1963)

The Low-Rise Speculative Apartment, Wallace Francis Smith (1964)

Palms-Mar Vista-Del Rey Socioeconomic Study, City of Los Angeles (1970)

“Palms-Mar Vista Preliminary Plan Calls for Apartment Zone Rollback”, LA Times (January 23, 1972)

“West LA Plan Proposals Face Bitter Opposition”, LA Times (June 29, 1972)

“Resident, Developers Angered by Proposed Plans for Century City”, LA Times (August 13, 1972)

“Planners Will Tackle WLA Traffic Problems”, LA Times (November 12, 1972)

“Traffic Fears Delay WLA Plan’s Approval”, LA Times (November 19, 1972)

“West LA Plan Foretells Severe Traffic Congestion”, LA Times (March 11, 1973)

“West LA Plan Approved Over Protests Noise Was Ignored”, LA Times (November 15, 1973)

“West LA Plan OKd, Called Move Away From Autos”, LA Times (December 20, 1973)

“Mar Vista Resident Group Hits City Plan”, LA Times (February 24, 1974)

“Palms-Mar Vista Plan Approved”, LA Times (December 26, 1974)

“Environmentalists ‘Sweep’, Community Plan Wins Approval”, LA Times (April 24, 1975)

Revelations on Carmageddon

In the summer of 2011, with the 405 through Sepulveda Pass set to close for construction, there were so many dire warnings of epic traffic jams that a new portmanteau, Carmageddon, was born. When the congestion failed to materialize, Streetsblog took a victory lap and declared that it was now apparent that LA doesn’t need so many freeways. Now, it’s Randal O’Toole’s turn to gloat, asserting that the BART strike has revealed the system to be unnecessary. (Although since it’s O’Toole, you have to consider the possibility that he had that post finished the day before the strike and so all he’d have to do is hit “publish”.) There are other similar examples of closures that were not known quite as far in advance: the closure of the 10 and the 14 after Northridge, the MBTA Green Line getting flooded, and so on. Why don’t the traffic prophesies bear out?

The answer is pretty simple. Cities are dynamic systems and people adjust. The predictions are silly because they assume a static system. The interesting thing to me is the apparent lack of curiosity about the knock-on effects of those adjustments.

Example: I’m right-handed; so let’s say I break my right hand. The static analysis says that my work and blogging productivity will go to zero because I can’t type, and that in a couple weeks I’ll starve to death because I can’t eat. Now obviously, that’s not going to happen. I’m going to type and eat with my left hand. I’ll type slower and I’ll probably spill coffee on myself, though I will get a little better with time.

There are two important takeaways here. One, the fact that I survive breaking my right hand does not mean that it is useless. Really, that reveals nothing about its utility for my survival. Its utility is shown by all the things I use it for when I have the ability to use it. Likewise, the utility of transportation is demonstrated by the people using it. Just because a city survives having a piece of infrastructure closed, it does not mean the infrastructure is useless. There is plenty of useless infrastructure in the United States, and it is self-evident because it is there and it has no users.

Second, even though I survive, there are still negative effects, because I get less work done and I ruin some of my clothes with coffee stains. In the case of cities, these losses are social and economic, manifest through lost economic activity, additional commuting time, etc. The losses diminish with time as people adjust, but the shadow can be very long. If I lose my right hand, I’ll recover some of my abilities in time, but I’ll never be able to do everything I could if I had both. The effects can be cumulative – if enough city infrastructure is broken and not replaced, the city will decline.

Finally, it is worth noting that there are cases where the loss of infrastructure does result in crippling traffic jams. This occurs when the disruption was not foreseen or when its magnitude was misunderestimated. The most common example is snowstorms, but even then, the system adjusts – if the roads are still blocked the next day, no one goes out. Likewise, if I order a steak for dinner and then discover I have somehow broken my hand splitting a dinner roll, I’m going to be pretty screwed that night because I won’t be able to cut my steak. But the next night, I’m not going to order another steak, knowing going in that I won’t be able to cut it.

We’re getting another experiment today with the 5 freeway closed at the interchange with the 2 due to the gas tanker spill and fire. Here’s betting that traffic won’t be as bad on Monday, since people have had time to plan ahead, as it was on Saturday, when everyone was caught off-guard. But remember, no matter what happens, it won’t tell us very much about the long-term effects of changes to the transportation network.

Like I said, I find it interesting that people seem relatively uninterested in those effects, because if you’re going to talk about eliminating infrastructure, that’s what matters.