Depaving Roads
Nov. 19th, 2021 12:02 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
ysabetwordsmithNow here's an example where it makes good sense to depave: low-traffic rural roads. Farm-to-market roads are used primarily by farmers driving tractors or pickup trucks, and most other rural folks also drive vehicles suited to rugged conditions. Because you never know when you'll have to pull into the ditch to get away from a tractor that is twice as wide as the road.
Let's take a look at some surfacing options:
Gravel -- usually the cheapest, and it actually has a decent lifespan if you don't run snowplows over it throwing out gravel along with snow. If you plow the road, you'll have to replenish it more often. A drawback is that it can develop fucking awful washboard grooves that are difficult to remove. This is standard for low-traffic backroads, and used to be so for all the farm-to-market roads. Some of the oldest roads or paths known are gravel or dirt and still in use.
Road oil -- actually, a mix of road oil and gravel, which is still cheap but more durable than gravel alone. It uses a fossil resource and is noxious, but it supports more traffic than gravel and is less hazardous to fragile city vehicles. This is the current standard for most farm-to-market roads. It stands up pretty well to snowplowing. It's a nice upgrade but not really necessary.
Asphalt -- currently a popular paving in suburban areas and smaller towns because it's fast and relatively affordable. It makes a nice surface when new but as it wears out it gets crumbly, leading to potholes, and at this stage gets rapidly worse if snowplowed. Patching it effectively is possible but difficult.
Brick -- formerly very popular, now seen mostly on historic streets. It produces a tolerably smooth, non-muddy surface made from sustainable materials, and it lasts pretty well as long as it doesn't get heavy traffic. It's particularly good for pedestrian streets and will last quite a long time that way. A key advantage is that it's permeable to rainwater, but much cheaper than modern permeable pavement. It's also easy to patch because the surface is modular. Other types of modular paving are often similar, but cobblestones are inferior due to their rounded texture and boneshaking ride. Some of the oldest roads or paths known are brick or stone and still in use.
Concrete -- currently the standard for urban and nicer suburban roads, it produces a smooth and reasonably durable surface. You can pay extra for the kind that lasts even longer. However, it's more brittle than other options, and in cold climates this is a real problem. Once it starts to crack it gets bad potholes, and snowplowing makes them worse. It can't be patched effectively, although people try to fake it.
Permeable pavement -- you can get the kind that water will soak through, and the more expensive kind that's supposed to melt ice and snow. These have a smooth surface like concrete, and they're new enough that estimating durability and lifespan is iffy. They also cost an arm and a leg. Some cities use them to help reduce the need for stormwater control and snowplowing. Other fancy modern pavements with different features typically fall in this high-end range. It's worth a thought for downtown but likely unaffordable for most locations.
The size and type of road you need should be determined by location, traffic, local weather, and budget. Don't build more road than you need and can afford. But you if don't suit the quality of road to the vehicles driving it, then those vehicles will take damage, which gums up civilization on both sides of the road. That's why you can't put a rough road in the middle of town: it will fuck up the vehicles, your citizens will express their displeasure in the polls, and shippers will refuse to go there. But you don't have to put fancy roads in the middle of nowhere.
Let's take a look at some surfacing options:
Gravel -- usually the cheapest, and it actually has a decent lifespan if you don't run snowplows over it throwing out gravel along with snow. If you plow the road, you'll have to replenish it more often. A drawback is that it can develop fucking awful washboard grooves that are difficult to remove. This is standard for low-traffic backroads, and used to be so for all the farm-to-market roads. Some of the oldest roads or paths known are gravel or dirt and still in use.
Road oil -- actually, a mix of road oil and gravel, which is still cheap but more durable than gravel alone. It uses a fossil resource and is noxious, but it supports more traffic than gravel and is less hazardous to fragile city vehicles. This is the current standard for most farm-to-market roads. It stands up pretty well to snowplowing. It's a nice upgrade but not really necessary.
Asphalt -- currently a popular paving in suburban areas and smaller towns because it's fast and relatively affordable. It makes a nice surface when new but as it wears out it gets crumbly, leading to potholes, and at this stage gets rapidly worse if snowplowed. Patching it effectively is possible but difficult.
Brick -- formerly very popular, now seen mostly on historic streets. It produces a tolerably smooth, non-muddy surface made from sustainable materials, and it lasts pretty well as long as it doesn't get heavy traffic. It's particularly good for pedestrian streets and will last quite a long time that way. A key advantage is that it's permeable to rainwater, but much cheaper than modern permeable pavement. It's also easy to patch because the surface is modular. Other types of modular paving are often similar, but cobblestones are inferior due to their rounded texture and boneshaking ride. Some of the oldest roads or paths known are brick or stone and still in use.
Concrete -- currently the standard for urban and nicer suburban roads, it produces a smooth and reasonably durable surface. You can pay extra for the kind that lasts even longer. However, it's more brittle than other options, and in cold climates this is a real problem. Once it starts to crack it gets bad potholes, and snowplowing makes them worse. It can't be patched effectively, although people try to fake it.
Permeable pavement -- you can get the kind that water will soak through, and the more expensive kind that's supposed to melt ice and snow. These have a smooth surface like concrete, and they're new enough that estimating durability and lifespan is iffy. They also cost an arm and a leg. Some cities use them to help reduce the need for stormwater control and snowplowing. Other fancy modern pavements with different features typically fall in this high-end range. It's worth a thought for downtown but likely unaffordable for most locations.
The size and type of road you need should be determined by location, traffic, local weather, and budget. Don't build more road than you need and can afford. But you if don't suit the quality of road to the vehicles driving it, then those vehicles will take damage, which gums up civilization on both sides of the road. That's why you can't put a rough road in the middle of town: it will fuck up the vehicles, your citizens will express their displeasure in the polls, and shippers will refuse to go there. But you don't have to put fancy roads in the middle of nowhere.
