Are Public Roads Only For Cars and Trucks?

By Noel T. Braymer

My earliest memory of Streetcars was when I was about 6 years old and my father took me to my first baseball game. It was to see the now LA Dodgers playing at the Los Angeles Coliseum around 1958. What I remember most about that night were the Streetcars. They scared me a little but made an impression being large, loud with a rumbling sound as they passed, giving out sparks off the Trolley Pole and between the wheels and rails.

As I grew up I got the impression that Streetcars had to go because they disrupted auto traffic on busy city streets. Motorists often complained about the Streetcars. Was that really the problem? I was counting cars and timing them the other day on some streets. No 2 streets are the same so traffic flows vary. In a large congested city traffic often comes to a halt which means few cars are moving. But from counting cars while traffic was moving II rarely counted more than 10 cars a minute. If an intersection has traffic lights which most do in a city you can expect traffic on either of the two streets to be shut down half of the time. So on an urban street 20 cars a minute per lane is doing very well. Assuming 20 cars a minute that’s 1200 cars an hour. Most cars rarely carry more than 1 person and even 1200 cars an hour is optimistic so 1200 persons per lane in rush hour traffic is rarely attainable.

So let’s look at Light Rail on a city street. One Light Rail Car can seat roughly 80 passengers. A three car train then could seat 240 passengers. Let’s assume you run 10 trains an hour with 3 car trains. That’s 2,400 seats an hour for 3 cars trains or at least double the capacity of cars using a single lane of road in one direction. If a modern Light Rail Train uses a dedicated lane free of auto and truck traffic and has traffic signal prioritization it will be faster than auto traffic. Under those circumstances Light Rail trains will likely be full in rush hour. So what happens at rush hour? Most city streets become congested and traffic flows go down. In other words the streets most likely won’t be able to carry 1200 cars an minute per lane in rush hour.

But with Light Rail during rush hours with standees you can easily double your capacity without extra cars or trains. Now you are talking 4800 people or more per lane of city street with 3 car trains at 10 trains an hour in one direction. Now what happens if we double the number of trains by running 20 trains an hour during rush hour with a train every 3 minutes? That is around 9600 or more people able to travel on one lane of a city street in one direction in an hour. By auto you might get 1200 on a good day but rush hour is rarely a good time of day to drive.

But where would you find that that level of Light Rail traffic on a city street? Well in Los Angeles Light Rail trains now run with 6 minute headways, 10 trains an hour in each direction during rush hours. In downtown Los Angeles the Blue and Expo Light Rail Lines share Flower Street tracks north of Washington Blvd. Combined these 2 trains now carry over 110,000 passengers a day and can expect ridership to grow. Using city streets for Light Rail in Los Angeles is clearly getting more capacity from its streets with Light Rail on some streets.

A major cause of traffic congestion on city streets it turns out is parking. Both from cars slowing down or stopping while looking for a place to park on city streets or trying to get into or out of parking lots. Removing on street parking in many cities would improve traffic flows and create room for bike lanes, Streetcars or Light Rail using street space now used for parking while bringing more people to shop or for business in dense urban areas. Less parking improves traffic in cities. Clearly getting rid of the Streetcars didn’t fix traffic problems in the 1960’s; doing so made it worse.

In theory one freeway lane can handle 5,000 cars an hour. Freeways since they don’t have intersections and allow faster travel speeds by nature can carry many more cars than a city street. This was why freeways were expected to be the cure for traffic congestion 60 years ago. Freeway lanes however rarely carry 5,000 cars an hour in the real world. This is because drivers often cause congestion even though the freeways aren’t at capacity.

Trucks which accelerate more slowly than cars slows traffic flows on the freeway. Timid drivers will slow down for no apparent reason slowing traffic and reducing the capacity of a freeway lane. Aggressive drivers often cut off other drivers by making constant lane changes which forces the driver who are cut off to slow down which slows down traffic behind them. All these factors contribute to stop and go traffic for no apparent reason on freeways. Then there are also traffic accidents and vehicle breakdowns which are common causes of freeway congestion. In theory a 5 lane freeway can handle 25,000 vehicles a hour in one directions but this rarely happens. Five lanes is generally considered the maximum width of a freeway to operated effectively. This is because pulling off a freeway with car trouble in the middle of an 8 lane freeway will really create a back up.

With rail service we can easily run trains with ten or more cars. Assume a ten car train with 130 people in each car. This can be a subway or a commuter train. That is 1300 people on a train. Assume we run these trains every 3 minutes or 20 trains an hour which is 26,000 people an hour in one direction. This level of traffic is common with local rail services around the world. Subways have headways as short as every 90 seconds. That is 40 trains an hour which could carry 52,000 people per hour. Now with standees double deck commuter trains can carry over 400 passengers per car. At rush hour with standees that is at least 80,000 people that can travel on a single track in one direction in an hour with 20 trains an hour. Compare this to 25,000 cars an hour with 5 lanes of freeway which rarely happens in rush hour as capacity goes down as congestion increases. This would be very helpful in an emergency evacuation of a major urban area.

These realities should be kept in mind as demand for more and better rail service continues to grow. It will grow because car ownership is becoming less economical in terms of operating costs, land use and convenience. Cars are great when roads are free flowing and parking is readily available. That was often true in 1960 when California’s population was around 15 million and road construction was in full swing. But today California’s populations is at 38 million and is expected to be well over 40 million in ten years. These crowding problems will be worse in urban areas where most people in California live.

We should have more Steetcars projects, expanded Light Rail on city streets and use of Freeway rights of ways for new transit and High Speed Rail rights of way. Freeways are not the best places for stations but are direct ways to go fast. High Speed Rail and Intercity Rail for long distance travel could do well on freeway rights of way when there are no other economical alternatives. It is much cheaper and less of an impact on people than trying to create a new right of way buying private property or tunneling under cities.

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