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In praise of higher speed limits

It’s being discussed elsewhere how Texas raised the maximum speed limit last year to 85. The bill that did that was removing references to the Trans-Texas Corridor from statute, and it left that speed limit in place. That limit is unlikely to affect many roads.

There was another bill last year specifically about speed limits, and it will have a bigger effect. This bill cancelled the 65 mph night limit and 70 mph maximum truck limit, and raised the maximum limit on all highways to 75. Previously only highways in sparsely populated counties were allowed to have limits above 70. Nearly all rural Interstate highways that had limits of 70 have had limits increased to 75. Two-lane and four-lane roads are being studied and each month a few are approved for the higher limit.

I see obeying laws as a societal obligation, so I obey speed limits unless it’s unsafe to do so. Because of this, I have a history of being passed a lot. In my admittedly very limited experience, I’ve found that traffic on the Interstates with the higher limit (I’ve been on 20 and 35) is running noticeably more smoothly. Remember it isn’t just an increase from 70 to 75, but also an increase at night from 65 to 75. Previously I noticed more frequent and desperate passing, while now there’s much more occasional and gradual passing. I’m sure part of this is because I’m going faster and not being passed as much, but I notice the difference all around, not just right around me.

We seem to have found a speed limit that actually works. When I drive along at 70-75, day or night, traffic seems smoother. I still pass or get passed by a car or two, but not by big blocks of traffic. There’s the occasional speed demon and slowpoke, but mostly everyone seems to agree that 70-75 is the right speed. We’ll see what happens when more two-lane roads get speed limits of 75 in areas that aren’t ultra-rural. I’d be interested in seeing if there are any affects on road safety.

There’s still, of course, a lot of inordinately high speed on congested city freeways. I’d like someone to explain to me why people want to go so much faster when it’s most dangerous.

I remember reading some time back about a bunch of university presidents wanting to lower the drinking age to 18. They seem to think that the sense of rebelliousness and anarchy caused by knowingly breaking rules leads to heavier drinking, and that more permissive laws may reduce that. There seems to be a similar phenomenon with speed limits. Where the higher limits are posted, the rule-followers like me are going faster, and people seem more content and less desperate to get around everyone.

Like you, I drive 4 to 5 miles over the speed limit in the interest of traffic flow. Like you, I suffer a big
Penalty in gas consumption and increased accident potential because of loss of reaction time and increased severity of accidents. Like you…I rationalize the world is safer when driving faster…when it’s not.

If everyone drove 55 mph in a Lexus, imagine how much safer the highways would be…and supremely boring. 70 to 75 may be agreed upon but it has less to do with safety then it does the capabilities of the modern car. Many can easily cruise at a 100 mph. The higher the speed limit, the greater the speed variation and chance for more accidents.

I don’t see a problem with speed limits of 85 in rural areas in like Texas. There are probably long stretches of rural highway in Texas that’s longer then all of NH. Driving hundreds of miles on a long deserted highway shouldn’t be a problem at 85 or even 95.

@f848:

In my admittedly very limited experience, I've found that traffic on the Interstates with the higher limit (I've been on 20 and 35) is running noticeably more smoothly.

On one hand, you admit your experience is limited. On the other hand you seem to interpret your experience and conclude things are just as smooth for everyone.

Determining whether this speed limit “actually works” isn’t as simple as interpreting your experience.

Personally, I wonder how much these higher speed limits will increase demand for fuel and how much that will drive up the price of fuel. I also wonder about what will happen the next time the price of fuel spikes, and those who try to save fuel set their cruise control on 70 MPH in an 85 MPH zone. That sounds dangerous to me, at least as long as it is legal to drive 70 MPH in an 85 MPH zone.

In Central MD, the speed limit is 65 or 70 on most interstate highways. Yet, there are always people going 50 MPH; sometimes slower. Still, there are drivers going probably 80 MPH or faster at the same time. Because traffic accidents correlate to speed difference more that top allowable speed, raising the speed limit here would allow many more drivers to increase the difference between their speed and that of the slow drivers. That will likely lead to more accidents, even if it a one-car accident where the fast guy tries to avoid the slow one and runs off the road. The slow drivers aren’t just elderly ladies and gents with no particular reason to get somewhere at a specific time. I see more commercial box vans, specialty trucks and tractor trailers than cars going way under the posted limit. It won’t work were traffic is as heavy as it is here, but Texas and much of the Western USA have a different geography.

I lived in NE for seven years in Lincoln and Omaha the limit inside of the city limit is 60mph on I-80 between the two citits its 75mph my car at the time is 85 VW GTI it got better mpg using state highway 6at 60mph then 75 on i 80. todays car can cover long distances at high speeds(over 75mph). Thios past Nov. I drove from NJ to FL. car got about 24 to 28 mpg with my speed ranging from 65 to 90. I set my speed by the traffic, wheatrher cond. and what other people our doing at the present time and leave a space around my self is have the extra time i need to respond if i need tomy car needs more space to stop the faster i’m traveling. and rember on 2 lane roads pass left stay right and on 3 or more lane roads stay in the center lane till you get close to your exit. speed limitws are a crap shout .

Google “85th Percentile Speed” for some reading material about your post’s topic. Most drivers are reasonable people and will drive at a speed that they consider to be safe.

But in the USA it appears that speed limits are set about 10 MPH below the 85th percentile speed. Is that so that we can get more speeding tickets?

If you look at the Wikipedia post on the subject, it shows that speed limit increases have generally led to more fatalities, and these were predominantly the increases from 55 MPH to 65 MPH. While you may feel safe at higher speeds, in reality you are not because injuries from higher speed crashes are more severe. You only guess that you might be safe because you haven’t been injured or killed yet.

Couple that with the unfathomable desire to tailgate no matter what speed we are going, and it’s a surprise that there are not more accidents than there are now. Going fast is not necessarily bad, but the rest of our driving mannerisms has to change to reflect the danger inherent in higher speed. Like stopping distance, for instance. If we’re driving identical cars, I’m going 55 in front and you’re going 75, then I have to panic stop, you will end up plowing into me at 55 MPH. What was once a 20 MPH difference got progressively worse until the accident when you were going 55. This hardly happens, but you can be sure that it does happen. Once is too often IMO.

I heard somewhere that helicopter pilots and traffic reporters noticed that traffic on interstates tended to “bunch up” into waves. The bunches would spread and consolidate with time as faster driver moved forward to the bunches in front and slower drivers would fall back to the bunches behind. I have found that to be true, even in heavy traffic, and try to stay positioned between the bunches.

I’m interested in what facts present themselves. My observation is that I’m passed by one or two vehicles at a time now, instead of blocks of them, and the passing visible ahead of me is more gradual and less urgent. But what really matters are facts. There seems to have already been some facts assessed, as the new 75 zones were recently pulled back further from San Antonio. I really think the 75 zone should be pulled further back from Austin and that 75 is too fast for Midland, but we’ll see what the experts determine.

I’m not a fan of high speed. For the sake of safety and efficiency, I personally wouldn’t mind a universal speed limit of 60 or 65, so long as it was obeyed. Several times I’ve driven hundreds of miles at 60 and found it to be fast enough. But since most people go faster than that, I so far like the higher limits, particularly at night. The traffic I’ve been in was rolling along pretty steadily at 70-73 and without the night limit of 65 me and the other rule-followers can keep up.

We’ve already had long, drawn-out debates on this issue. I think I’ll refrain from joining this one.

Couple that with the unfathomable desire to tailgate no matter what speed we are going, and it's a surprise that there are not more accidents than there are now.

I have a friend who tailgates constantly. It results in him accelerating hard and braking hard very frequently. I’ve tried to explain, but he simply won’t understand how this is dangerous, inefficient, and doesn’t even get him where he’s going any faster. I’m the opposite. In city traffic, I try to hold a steady speed and avoid needing to stop, and, of course, people constantly get in front of me so they can hurry up and hit the brakes.

I agree that it’s the speed variances that cause accidents. I also would not like to live with a ‘double nickel’ speed limit ever again. IMHO, not all of life is about being constantly protected about what might happen 100% of the time.

I think the answer is education, as much as can be done anyway. Teach people the right lane is for slower traffic and the left lane is for passing. Ticket slow people in the left lane and people passing on the right. If we had a more European-style of driver education here, I think there would be less problems. Maybe not everyone would get their license at 16 or keep it as long as they do, but the roads might be a little safer.

I have a friend who tailgates constantly. It results in him accelerating hard and braking hard very frequently

Tailgating is the NORM in MA and southern NH. Far more people tailgate then people who don’t tailgate. Far more then any other place I’ve driven in this country. It’s not uncommon to see 10+ cars in a row doing 75…all about 5’ from the car in front of them. And heaven forbid if you actually leave enough room between you and the car in front of you…within minutes you’ll find 4-5 cars have squeezed into that space.