Why are there "driveway connections by permit only" signs on roads?
I get signs telling you there's a bump ahead, or deer might run out in front of you, but I've never understood why there are signs telling people not to build unlawful driveways. Are that many people doing it on a daily basis in that area that they need a fully visible sign? Surely it's just an ordinance, why does it need a road sign?
I've been wondering this for years and hope someone has an answer that makes sense.
I've never seen such a sign, but I'll take a guess what it might be referring to. Here in California, the definition of a freeway does not have anything to do with number of lanes, speed limits, the presence of freight traffic, or any affiliation with the National Highway System. Instead, it is defined in the California Vehicle Code section 332 as:
a highway in respect to which the owners of abutting lands have no right or easement of access to or from their abutting lands or in respect to which such owners have only limited or restricted right or easement of access.
This roughly corresponds to what the Wikipedia describes in its page on "controlled access highways", a term which includes the California and USA federal government's term of freeway or the eastern US states' term of expressway or the British motorway. That is, a road which all ways onto and off of the road are carefully crafted.
There are many roads in California and the United States which will meet the requirements outlined by the Interstate Highway standards, and will look and feel like an interstate freeway, from the signs and lane markings and shoulder sizing.
But none of that matters for the California legal definition of freeway. Indeed, some freeway-looking roads will have signs that say "end freeway" or "start of freeway" with no other visual cues. And this is because the California Department of Transportation (CalTrans) has not acquired the property rights from adjacent landowners to prohibit building driveways onto the public right-of-way.
To clarify, a right-of-way is not an individual right like free speech or freedom against unreasonable searches. Rather, it's a legal term referring to a property right, namely a grant of access on/over some piece of property in order to cross it. In the case of public roads, the property right is held by a public entity, and that means the public can use it. Since a right-of-way is a type of property, there are rights implied by a right-of-way. So a right-of-way right. Yeah, lawyers named things badly here. Anyway...
A feature of public rights-of-way is that any adjacent private properties can connect to and travel upon the right-of-way. The rationale -- to oversimplifying things -- is that if the public entity could deny the right -- including to build a driveway -- then a property could end up with zero ways to access it without trespassing, making it impossible to enter or exit, which makes the property near worthless. It is an age-old rule from English Law that rendering property worthless is bad, so private property rights necessarily comes with an implicit ability to connect to adjacent public rights-of-way.
But property rights are a bundle which can be sold separately by their owner. For example, many suburban property owners don't own the rights to minerals underneath the land, since the preceding developers sold that right to someone else. And so the state -- through CalTrans -- or the city or county can buy (often through eminent domain) just that single right from the property owners. Thus, the properties along a road might -- unnoticeable to the naked eye -- not be legally allowed to build a driveway, having shed that legal right away by forced-yet-fully-compensated sale.
To that end, it's possible that a sign warning against illegal driveways is the state's way of preventing future land owners from trying to build such driveways, since those owners would lose in court. If the state has acquired such rights, it's usually because the road is planned to become a freeway or expressway (a limited-access road, in California terminology), or they wish to preserve that possibility early and for cheap. So far as I'm aware, in California the right is only ever acquired for state roads, with the sole exception of the expressways in Santa Clara County, because they planned well ahead in the 60s.
Other states may be similar, by extrapolation.
TL;DR: OP's state might be hedging their bets to build a future freeway, and wants to prevent future legal issues with landowners, since the state knows it would win those cases
Another possibility is related to a [citation needed] claim about the Romans and their roads. Roman roads are remarkable in that some have stood the test of time, some still recognizable today, I'm told.
Supposedly, Roman roads were engineered as all-weather roads because their engineers understood the importance of drainage. Water destroys all, in what we understand today as freeze/thaw cycles and soil erosion undermining the road foundation.
It is said [again, citation needed] that the penalty for messing with the drainage of a Roman road was severe, possibly being the death penalty.
As roads then and now are often constructed with flanking drainage ditches, adding a driveway would necessarily affect the drainage of the road if done improperly, so perhaps some jurisdictions prohibit driveways additions unless properly engineered and permitted.
No problem! This is a topic which I've been strangely fascinated for years about, although we'll might not know if it actually answers the case that OP described.
This kinda all started when I was learning how to drive, and kept seeing people online talking about how "in California, no one has the right of way, but can only yield it". This was puzzling to me as a student driver, because obviously I have the right to the street if I'm in it.... right? No.
It all made sense when I finally determined after some research that "right-of-way" meant the property that the state/county/city owns, meaning that all the drivers are temporary guests upon the right-of-way, and thus have to yield it to each other in an orderly fashion, like passing around a can of Axe body spray in the high school locker rooms.
Indeed, driving in California doesn't really have any absolute rights whatsoever, since no situation affords anyone an absolute ability to do something. A green light doesn't mean blindly drive into an intersection, since the Anti-Gridlock Act of 1987 prohibits causing actual gridlock, and pedestrians can still cross if they entered lawfully, among other things. Even an ambulance or fire-truck cannot blindly drive waywardly into the street, expecting everyone to get out of the way. There are enough rules that it's easier to just say no rights really exist, and everyone just has to calmly and fairly cooperate so that everyone makes it home alive.
Suffice it to say, there are zero absolutes. And that's probably for the best, since if there were absolutes, so-called self-driving cars would probably be mowing down pedestrians, cyclists, and other motorists with full force of law.
There's also the whole topic about property and property rights that could put first-year law students to sleep, about how a separated property right can in-fact be a property unto itself, with its own rights about how it can be disposed of, and with whose permission. It's rights all the way down lol