Default speed limits

[PHLBOS]

If a road is not signed, what would be the default speed limit? Does it vary by state?

Yes to your 2nd question.

[ET21]

The only two I know of locally is alleyways are 5 mph and open rural roads are 55 (45 for the isolated gravel one)

[Duke87]

The speed limit in Connecticut is 30 MPH unless otherwise posted.

Connecticut speed limits are low.

[roadman65]

The speed limit in Connecticut is 30 MPH unless otherwise posted.

Connecticut speed limits are low.

Tell me about it, I drove US 7 through it and only the freeway portions were at 55 mph.  Of course that is only between Danbury and New Milford, where everything else is two lanes and arterial.  Therefore the speed limit was only 40 mph (maybe 45 in some spots) even in the rural areas of NW Connecticut.

[roadfro]

Nevada only has one default speed limit:

Nevada Revised Statutes, Chapter 484

   NRS 484B.600  Basic rule; additional penalties for violation committed in work zone or if driver is proximate cause of collision with pedestrian or person riding bicycle.

      1.  It is unlawful for any person to drive or operate a vehicle of any kind or character at:

      (a) A rate of speed greater than is reasonable or proper, having due regard for the traffic, surface and width of the highway, the weather and other highway conditions.

      (b) Such a rate of speed as to endanger the life, limb or property of any person.

      (c) A rate of speed greater than that posted by a public authority for the particular portion of highway being traversed.

      (d) In any event, a rate of speed greater than 75 miles per hour.
<snip>

[froggie]

Vermont clearly signs a default speed limit of 50 mph at its borders.

With two categories above that.  Default (unless otherwise signed) for limited-access highways is 55 MPH, whereas the default for rural 4-lane freeways (this to include US 4 west of Rutland) is 65 MPH.

Not every town follows the 50 MPH default either.  Some towns set their default at 35 MPH, though this is not applicable to state highways.

[SSOWorld]

The speed limit in Connecticut is 30 MPH unless otherwise posted.

Connecticut speed limits are low.

New nickname for the state based on at least two cases (the other being the NEC rail) - "The antiquated state"

[myosh_tino]

Default speed limits for California...

15 MPH
* uncontrolled railroad crossing (i.e. no flagger or electronic gates & lights)
* uncontrolled, blind intersections
* all alleys

25 MPH (does not apply if the road is a state highway)
* within all business districts and residential areas
* school zones
* senior citizen facilities

55 MPH
* 2-lane undivided highways

65 MPH
* multi-lane highways

Of course, the maximum speed limit in California is 70 MPH.

[Billy F 1988]

Montana's defaults are (if my knowledge serves me):

Between 25-45 for local streets not including highways or interstates.
Between 55-70 for state highways, 60 for trucks.
70 for US highways, 60 for trucks, except when entering a community like Missoula, Polson, etc.
75 for I-15, 90 and 94, 65 for trucks.

[corco]

Between 55-70 for state highways, 60 for trucks.

Default is 70/60 on state highways, even unpaved state highways unless otherwise posted. Some state highways have speed limits between 55 and 70, but they're posted as such so it's not the default speed. If you turn on a state highway and there's no speed limit sign, the speed limit is 70.

Here is the MCA to that effect http://leg.mt.gov/bills/mca/61/8/61-8-303.htm

I know my county's speed limit is 35 on county roads unless otherwise posted, but there's very few speed limit signs. I think the Ovando-Helmville backroad (55) is the only exception to that rule. Oddly, I can't find that statute that authorizes that without doing an engineering study on all the roads, and I guarantee our county has never done that (unless "engineering study" can be interpreted really loosely). It may be illegal, but I don't think our barneys have ever written a speeding ticket on a county road anyway.

I've researched our road history in detail (searching the commissioner's journals for every single mention of the word "road" or "highway"), but for abandonment/establishment reasons- I didn't document the speed limit fiasco as I was researching this, but I know the speed limit on county roads didn't come into effect until Montana went "reasonable and prudent"- county roads were 55 prior to that time in accordance with NMSL. After NMSL was repealed, people started hauling ass on county roads, freaking people out and damaging the roads (we have very, very few miles of paved county road), causing the commissioners to pass an emergency resolution declaring the speed limit to be 35. At some point that was rolled into a normal resolution, and they've been 35 ever since, perhaps illegally. Given the state of documentation on road abandonments (I found several roads that we didn't know we had, and a few that we thought we had abandoned but never actually finished abandoning), this wouldn't surprise me.

[doorknob60]

In Idaho, I've noticed a lot of these signs:

Entering Caldwell:

If you can't read it, the bottom says "UNLESS OTHERWISE POSTED"

Entering Nampa:


(Both pictures from Google Street View)

These signs are both posted on arterials with a 45 Speed Limit. The first one in particular could be confusing, because if you aren't familiar with it, it looks like a instant drop from 45 to 20.

I've never seen anything like that in Oregon (that has well defined default speeds), so I'm guessing Idaho doesn't have much in the way of state defaults, leaving it up to local jurisdictions.

[cl94]

There are a bunch of signs like that entering New York City, even on expressways and parkways. If posted on a road with a higher speed limit, the higher speed limit is usually posted immediately after this sign. Rarely do I see somebody slow down from 55+ to 30 when they cross the city line.

Everywhere else in the state uses the aforementioned "village/city/town/area/etc. speed limit" signs instead of these. I have always wondered why NYCDOT hasn't switched over.

[webfil]

If I get it good, in the province of Québec, the default speed limit is 50 km/h (30 mph).

A municipal entity can lower its default maximum (and minimum) speed on the streets under its jurisdiction. Thus, in 2009, the city of Montréal lowered its default speed limit to 40 km/h (25 mph), except on the arterial network where it remained at 50 or was raised to 60 (37 mph) on controlled-access roads. That is why you might see "MAXIMUM 40 SECTEUR" (Maximum 40 Area) signs when driving the streets of MTL.

[hm insulators]

300,000 kilometers per second, everywhere.


And it's strictly enforced.

Some neutrinos occasionally claim to have exceeded the limit, but it's usually experimental error. Make sure your fiber couplers are securely fastened!

Theoretically, it is possible to travel faster than the speed of light, but I'll let the physicists explain that one

I wouldn't want to go faster than the speed of light anyway because then my hat would blow off.

[Brandon]

300,000 kilometers per second, everywhere.


And it's strictly enforced.

Some neutrinos occasionally claim to have exceeded the limit, but it's usually experimental error. Make sure your fiber couplers are securely fastened!

Theoretically, it is possible to travel faster than the speed of light, but I'll let the physicists explain that one

I wouldn't want to go faster than the speed of light anyway because then my hat would blow off.

    Junior: Daddy, my hat blew off!
    Sheriff Justice: I hope your God damn head was in it!

[doorknob60]

There are a bunch of signs like that entering New York City, even on expressways and parkways. If posted on a road with a higher speed limit, the higher speed limit is usually posted immediately after this sign. Rarely do I see somebody slow down from 55+ to 30 when they cross the city line.

Everywhere else in the state uses the aforementioned "village/city/town/area/etc. speed limit" signs instead of these. I have always wondered why NYCDOT hasn't switched over.

I should have mentioned that probably 100 ft or so after the SPEED LIMIT 20 UNLESS OTHERWISE POSTED sign, there is a standard SPEED LIMIT 45 sign, so if you drive through there once, it's pretty obvious what you're supposed to do. Then again, some people are stupid.