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Driving Tips and Interesting Things About Traffic

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Well, after reading Tom Vanderbilt’s book on traffic and talking to Caltrans and L.A. City traffic experts, I learned some helpful and fun things about driving. Here they are in no particular order.

Lane changes: Don’t bother. Studies show that in heavy freeway traffic it is not worth changing lanes. Although it may SEEM as though cars in the other lanes are moving faster, it is something of an optical illusion. That’s because as we face forward we can see cars passing us more easily than we notice the cars that we are passing. In the end, you don’t save much time switching lanes all the time. Note: 10% of crashes are due to lane changes.

Searching for the perfect parking spaces: Studies show that searching for the closest parking space doesn’t save any time. In the time it takes to find the closer space, you could walk to the store.

Backing out of parking spaces: If it seems people long to back out of parking spaces, they do. Drives do take longer to back out of a parking space when there is another driver waiting for it. Studies show people are more sensitive to losses than gains. So you may be more sensitive to giving up a space when someone else wants it, even if you don’t need it anymore.

Synchronized lights: People complain about lights not being synchronized. In fact, most southern California cities have sophisticated synchronization technology. And if the streets were laid out in a perfect grid you could synchronize lights easily. But left turn lanes, angled streets, complex intersections and differing streets widths make synchronizing an imperfect task. Also, when the lights are too well synchronized it can invite speeding and even dangerous racing.

Messy exits: Want to create congestion? Just make a fast last-minute exit across freeways lanes in heavy traffic. You may make it to you off ramp, but you’ll start a “wave” of brake lights behind you that will continue to slow traffic well after you are off the freeway.

Merging in construction areas: When construction requires that a lane or two are closed, and traffic has to merge, it’s actually best to merge later than earlier. Think of it this way, any unused road pavement is a wasted asset. So if everyone merged early, a good part of a lane would go unused. That’s inefficient. Engineers have set up “Late Merge” systems to compress the merge zone into a single point. This resulted in a 15% improvement in traffic flow.

Three for a carpool: Some of our carpool lanes may soon require 3 people per vehicle instead of the current 2. Why is that? Because there are federal standards for carpool lanes that require an average speed of 45 mph or more. A few southern California carpool lanes don’t meet that standard. By increasing carpools to 3 or more people, the number of carpoolers will drop and average speeds will go up.

Traffic info at your fingertips: You know those traffic message boards that tell you how many minutes it is to various freeways? Well you can access that info directly. Just go to www.dot.ca.gov/travel/index.php. There you can see all the messages that are on the freeway message boards, and live traffic from all the Caltrans freeway cameras. Check it before you leave for work or home. Very handy.

511 in our future: You may have heard of the 511 system. It’s a three-digit number that connects you to road info. San Diego and Bay Area already have it. This is a national program would replace the hundreds of different numbers that exist for travel information. It is coming to the L.A. area but it takes a lot of coordination, e.g. mobile phone companies have to agree to pass the call thru for free, etc.

Why are there are no carpool lanes on the 101 through the Valley? The short answer is, local homeowners groups have fought the idea whenever it’s come up. Part of the problem is that lanes are required by federal law to be a certain width. And the 101 freeway is not very wide. A carpool lane would require acquiring land/properties along the freeway. Not a popular idea.

The best anti-congestion tool? Charging people for driving. It’s true, the most effective decongestion policy in cities around the world is congestion pricing. It means paying a toll to drive into congested areas or during rush hour. Planners are exploring it for the L.A. area. For example, we could convert some carpool lanes to toll lanes, meaning that BOTH carpoolers and toll-payers could use the lane. They would go from HOV (High Occupancy Vehicles) to HOT lanes (High Occupancy Toll lanes).

Traffic Nirvana. Engineers have something they call “traffic nirvana”. It refers to the maximum efficiency of traffic volume. Nirvana turns out to be 2400 cars traveling at 55 mph passing a particular sensor each hour. If traffic gets denser, then it slows down. If traffic gets lighter it moves faster, but there are fewer cars moving. Nirvana it seems is as hard to attain on the roads as in life.

LEAVE A COMMENT Leave Comment  

First a suggestion.

The signs on freways that tell you x miles to exit y and x miles to exit z should have red/yellow/green lights to inform drivers of traffic speeds ahead. That way drivers could exit early to avoid traffic congestion ahead. Getting cars off could help decrease that congestion.

Second a suggestion.

You talk about the late merging being good in construciton areas. That may be well and good during times of heavy traffic, during light traffic early merging is better.

http://www.dot.state.mn.us/newsrels/03/10/29merge.html

Dynamic Late Merge Systems are the answer.


Third a question

Why no mention about merging at on-ramps? Drivers should merge early and not wait for the on-ramp to disappear. On west highway 60 at Grove Ave in Ontario there are many accidents from the late mergers.

Lastly another suggestion

People need to learn cooperative driving techniques. For instance at a traffic light they should position themselves so that vehicles can take the right portion of the right lane to allow cars to turn right onto an intersecting street. This will help reduce the number of cars at a given intersection, improving the number of cars that can make a light when it is green.