Municipal development staff worker here. Sidewalk networks are a bitch to implement.
Say you want to put in 6ft sidewalks on either side of a one-land road with a turn lane:
You have a ROW width of 50 feet. With the Existing road, shoulder, storm sewer, and utilities, you have no more room. So you either need to expand the ROW or build the sidewalk on private land.
Expanding the ROW has 2 realistic options. Imminent Domain or ROW dedication as part of the platting process. Imminent Domain is politically impossible in most cases, and if land is already platted, it may not get replatted for another century.
So you have to build it on private land. Most of the time, that takes the form of requiring sidewalk standards as part of site development. That works pretty well, but it requires all the private land in the entire network to re-develop. It’s why you see these weird sidewalks in front of newer business parks that are 50 feet long and don’t connect to anything. When the next property re-develops, they have to connect, but it doesn’t really mean anything until all the properties develop. And “Jimbo’s thrift shop, billboard, fire hazard, gun range, and playground” makes buckets of money by not meeting any modern building, planning, or health codes, so they’ll NEVER re-develop because they’d lose their existing non-conforming (grandfathered) status that allows them to keep doing dangerous shit cheaply.
This is deeply fascinating and I need to hear more about businesses and sidewalks!
Why are some houses in my neighborhood missing sidewalks? I thought all houses had to have them! This is an individual house level, there’s no hoa or the like.
Lots of times, it’s because the house is older than the rules. Other times it may be because of a variance granted to that property. Variances are really only supposed to be granted when meeting code is otherwise essentially impossible because of a unique physical characteristic of the site, but the Board of Adjustments (appointees who decide zoning variances for the city in many states) is made up of political appointees, and the reality is that if everyone likes Dave he gets what he wants even though he shouldn’t.
The area is old, and the houses weren’t here in the 70s (but were here by the 90s) so it feels like the rules should be 90s. But that’s my soup brain going everything should be around by the 90s, maybe.
I’ll blame it all on this mysterious Dave letting these people not have sidewalks when it would be really nice to have sidewalks all the way to the end of the fucking block so I can walk to my polling place without walking into the street.
By the time you’ve added curbs and striping, you’re looking at about 15 feet per auto lane. One lane each direction and a dedicated turn lane, and you’re at 45 feet. That leaves 2.5 feet on each side of the road for drainage infrastructure and utility lines.
It’s actually 12 feet per lane, plus a little extra for striping with a center turn lane, plus a small shoulder and curb. It ends up averaging about 40-45 feet depending on the road classification.
Roads have center turn lanes for a variety of reasons. A big one is so that people turning left don’t stop traffic…Not only is it good for traffic control, but it improves safety during peak traffic because you don’t have impatient assholes whipping onto the shoulder (or sidewalk or bike lane) when someone is trying to turn left.
It also gives room for traffic diversion in case of a wreck, breakdown, or construction while still allowing traffic to flow both directions. Just throw down some cones and make it work.
The width of the lanes is for fire trucks. the middle lane is for flexibility and traffic management. It’s not that complicated.
There’s no efficiency increase in road safety and traffic management greater than the transition from 2-lane to 3-lane.
Go out on winding country roads without a turn lane and the fatality rate skyrockets, because people end up drifting into the center 2-3 feet as they speed around curves, and when people are doing that in both directions, you have offset head-on collisions, which are some of the deadliest crashes.
Having that middle turn would allow those cars to miss each other by 6 feet instead while providing greater visibility in the turn. It also allows cyclists to ride on the edge of the road while giving motorists room to pull slightly into the middle to pass without going into ongoing traffic so long as there isn’t someone actively turning im that same spot - in which case the motorists can drive slower for 20 feet then pass the cyclist.
If that middle lane was swapped for a bike lane, you’d have cars using the bike lane to pass people instead, which is much more dangerous to the cyclists.
If you have a grade-separated bike lane, then you have nowhere to route traffic in the case of a wreck or construction.
Ideally, you’d have separate lanes going each direction, separated protected cycling and biking lanes, and rail in the middle. But that takes a whole lot of space and only really works in extremely dense metro areas. For most cities, that isn’t practical.
What many places are doing now is expanding the ROW corridor to 60 or 70 feet so sidewalk or ped lanes can be added, but it takes decades to get all that ROW. Hell - we still haven’t got the 50 feet everywhere in the city where I work. We’ve got places where the ROW is 30 feet, so it’s single-lane, no shoulder, no sidewalk, no stormwater system, and utilities buried under the pavement (huge PITA when a water or gas line breaks under the road).
Fixing this shit requires space, and getting that space takes time.
So you make the cars slow down. You narrow their lanes and put a median in. Add speed bumps or pavers if necessary. Here in Hanoi (terrible example), you’re lucky if you have 30’ ROW on non-thourghfare roads. If cars need to go long distances, they take the highways. When they’re on streets, they go slowly, stopping to crawl around eachother when they need to pass, not insist its their God-given right to barrel down a street at 80 km.
America has the weirdest solutions to the weirdest problems.
Municipal development staff worker here. Sidewalk networks are a bitch to implement.
Say you want to put in 6ft sidewalks on either side of a one-land road with a turn lane:
You have a ROW width of 50 feet. With the Existing road, shoulder, storm sewer, and utilities, you have no more room. So you either need to expand the ROW or build the sidewalk on private land.
Expanding the ROW has 2 realistic options. Imminent Domain or ROW dedication as part of the platting process. Imminent Domain is politically impossible in most cases, and if land is already platted, it may not get replatted for another century.
So you have to build it on private land. Most of the time, that takes the form of requiring sidewalk standards as part of site development. That works pretty well, but it requires all the private land in the entire network to re-develop. It’s why you see these weird sidewalks in front of newer business parks that are 50 feet long and don’t connect to anything. When the next property re-develops, they have to connect, but it doesn’t really mean anything until all the properties develop. And “Jimbo’s thrift shop, billboard, fire hazard, gun range, and playground” makes buckets of money by not meeting any modern building, planning, or health codes, so they’ll NEVER re-develop because they’d lose their existing non-conforming (grandfathered) status that allows them to keep doing dangerous shit cheaply.
This is deeply fascinating and I need to hear more about businesses and sidewalks!
Why are some houses in my neighborhood missing sidewalks? I thought all houses had to have them! This is an individual house level, there’s no hoa or the like.
Lots of times, it’s because the house is older than the rules. Other times it may be because of a variance granted to that property. Variances are really only supposed to be granted when meeting code is otherwise essentially impossible because of a unique physical characteristic of the site, but the Board of Adjustments (appointees who decide zoning variances for the city in many states) is made up of political appointees, and the reality is that if everyone likes Dave he gets what he wants even though he shouldn’t.
The area is old, and the houses weren’t here in the 70s (but were here by the 90s) so it feels like the rules should be 90s. But that’s my soup brain going everything should be around by the 90s, maybe.
I’ll blame it all on this mysterious Dave letting these people not have sidewalks when it would be really nice to have sidewalks all the way to the end of the fucking block so I can walk to my polling place without walking into the street.
Thank you!
You’ve got 50’ of ROW but still need more for sidewalks? 🙄
By the time you’ve added curbs and striping, you’re looking at about 15 feet per auto lane. One lane each direction and a dedicated turn lane, and you’re at 45 feet. That leaves 2.5 feet on each side of the road for drainage infrastructure and utility lines.
Where do you put the sidewalk?
Why the left turn lane? 15’ per auto lane?
It’s actually 12 feet per lane, plus a little extra for striping with a center turn lane, plus a small shoulder and curb. It ends up averaging about 40-45 feet depending on the road classification.
Roads have center turn lanes for a variety of reasons. A big one is so that people turning left don’t stop traffic…Not only is it good for traffic control, but it improves safety during peak traffic because you don’t have impatient assholes whipping onto the shoulder (or sidewalk or bike lane) when someone is trying to turn left.
It also gives room for traffic diversion in case of a wreck, breakdown, or construction while still allowing traffic to flow both directions. Just throw down some cones and make it work.
No offense, but your response is classic American traffic engineer Stroad-design. “Need big wide stroad to improve peak traffic!”
The width of the lanes is for fire trucks. the middle lane is for flexibility and traffic management. It’s not that complicated.
There’s no efficiency increase in road safety and traffic management greater than the transition from 2-lane to 3-lane.
Go out on winding country roads without a turn lane and the fatality rate skyrockets, because people end up drifting into the center 2-3 feet as they speed around curves, and when people are doing that in both directions, you have offset head-on collisions, which are some of the deadliest crashes.
Having that middle turn would allow those cars to miss each other by 6 feet instead while providing greater visibility in the turn. It also allows cyclists to ride on the edge of the road while giving motorists room to pull slightly into the middle to pass without going into ongoing traffic so long as there isn’t someone actively turning im that same spot - in which case the motorists can drive slower for 20 feet then pass the cyclist.
If that middle lane was swapped for a bike lane, you’d have cars using the bike lane to pass people instead, which is much more dangerous to the cyclists.
If you have a grade-separated bike lane, then you have nowhere to route traffic in the case of a wreck or construction.
Ideally, you’d have separate lanes going each direction, separated protected cycling and biking lanes, and rail in the middle. But that takes a whole lot of space and only really works in extremely dense metro areas. For most cities, that isn’t practical.
What many places are doing now is expanding the ROW corridor to 60 or 70 feet so sidewalk or ped lanes can be added, but it takes decades to get all that ROW. Hell - we still haven’t got the 50 feet everywhere in the city where I work. We’ve got places where the ROW is 30 feet, so it’s single-lane, no shoulder, no sidewalk, no stormwater system, and utilities buried under the pavement (huge PITA when a water or gas line breaks under the road).
Fixing this shit requires space, and getting that space takes time.
In the Netherlands, fire trucks are small enough to drive down the bike lane
American firefighters pack their gear like this:
Dutch firefighters pack their gear like this:
So you make the cars slow down. You narrow their lanes and put a median in. Add speed bumps or pavers if necessary. Here in Hanoi (terrible example), you’re lucky if you have 30’ ROW on non-thourghfare roads. If cars need to go long distances, they take the highways. When they’re on streets, they go slowly, stopping to crawl around eachother when they need to pass, not insist its their God-given right to barrel down a street at 80 km.