Safe Systems Civil Engineer
@cityengineer.bsky.social
PE. Dengineer. Safe network builder for people walking, in wheelchairs, cycling & driving. Train lover. Views my own - not speaking for any employer/board. Public sources only.
Pinned
If zoning didn’t exist, how much denser would the US be? How many fewer car trips? How many fewer cars? How many fewer deaths of people in cars killed? How many fewer deaths of people walking?
Housing Abundance
1.“No one talks about it.”
2.“Technocrats discuss it quietly.”
3.“Opponents caricature it.”
4.“Mainstream adopts a softened version.”
5.“It becomes obvious in hindsight.”
@davidsirota
@EmmaVigeland
@KimDriscollMA
1.“No one talks about it.”
2.“Technocrats discuss it quietly.”
3.“Opponents caricature it.”
4.“Mainstream adopts a softened version.”
5.“It becomes obvious in hindsight.”
@davidsirota
@EmmaVigeland
@KimDriscollMA
February 4, 2026 at 11:35 AM
Housing Abundance
1.“No one talks about it.”
2.“Technocrats discuss it quietly.”
3.“Opponents caricature it.”
4.“Mainstream adopts a softened version.”
5.“It becomes obvious in hindsight.”
@davidsirota
@EmmaVigeland
@KimDriscollMA
1.“No one talks about it.”
2.“Technocrats discuss it quietly.”
3.“Opponents caricature it.”
4.“Mainstream adopts a softened version.”
5.“It becomes obvious in hindsight.”
@davidsirota
@EmmaVigeland
@KimDriscollMA
Reposted by Safe Systems Civil Engineer
If nothing changes in Utah, they're basically guaranteeing that the state fall into a permanent California-style housing crisis that forces kids from the state to eventually move away. They need to reduce minimum lot sizes statewide.
www.housingwire.com/articles/uta...
www.housingwire.com/articles/uta...
Utah lawmakers target starter homes with lot size reform
Utah’s 2026 bill would reduce lot-size minimums to spur the construction of 35,000 new starter homes by 2028, addressing housing supply.
www.housingwire.com
February 3, 2026 at 11:05 PM
If nothing changes in Utah, they're basically guaranteeing that the state fall into a permanent California-style housing crisis that forces kids from the state to eventually move away. They need to reduce minimum lot sizes statewide.
www.housingwire.com/articles/uta...
www.housingwire.com/articles/uta...
“Lawmakers signaled that they were no longer willing to leave housing to the same local officials whose hostility to new construction created the shortage in the first place.”
www.bostonglobe.com/2026/01/29/b...
www.bostonglobe.com/2026/01/29/b...
Campbell sues nine cities and towns for rebuffing state housing law - The Boston Globe
Attorney General Andrea Campbell filed the suit against Dracut, East Bridgewater, Halifax, Holden, Marblehead, Middleton, Tewksbury, Wilmington, and Winthrop.
www.bostonglobe.com
February 3, 2026 at 11:48 PM
“Lawmakers signaled that they were no longer willing to leave housing to the same local officials whose hostility to new construction created the shortage in the first place.”
www.bostonglobe.com/2026/01/29/b...
www.bostonglobe.com/2026/01/29/b...
This systematic trend is illiberal and unprogressive in one of the most “progressive” places in America. More impactful
than healthcare & groceries. Let’s return to the widespread market affordability that existed for most of 20th century, before we turned “homes” into “investments” . #BackTo3
than healthcare & groceries. Let’s return to the widespread market affordability that existed for most of 20th century, before we turned “homes” into “investments” . #BackTo3
February 2, 2026 at 11:47 AM
This systematic trend is illiberal and unprogressive in one of the most “progressive” places in America. More impactful
than healthcare & groceries. Let’s return to the widespread market affordability that existed for most of 20th century, before we turned “homes” into “investments” . #BackTo3
than healthcare & groceries. Let’s return to the widespread market affordability that existed for most of 20th century, before we turned “homes” into “investments” . #BackTo3
Yes. Much safer for all users.
February 1, 2026 at 6:49 PM
Yes. Much safer for all users.
We are somewhere between 2 and 3 on #BackTo3
1.“No one talks about it.”
2.“Technocrats discuss it quietly.”
3.“Opponents caricature it.”
4.“Mainstream adopts a softened version.”
5.“It becomes obvious in hindsight.”
@davidsirota.com
@emmavigeland.bsky.social @kimdriscollma.bsky.social
1.“No one talks about it.”
2.“Technocrats discuss it quietly.”
3.“Opponents caricature it.”
4.“Mainstream adopts a softened version.”
5.“It becomes obvious in hindsight.”
@davidsirota.com
@emmavigeland.bsky.social @kimdriscollma.bsky.social
February 1, 2026 at 6:02 PM
We are somewhere between 2 and 3 on #BackTo3
1.“No one talks about it.”
2.“Technocrats discuss it quietly.”
3.“Opponents caricature it.”
4.“Mainstream adopts a softened version.”
5.“It becomes obvious in hindsight.”
@davidsirota.com
@emmavigeland.bsky.social @kimdriscollma.bsky.social
1.“No one talks about it.”
2.“Technocrats discuss it quietly.”
3.“Opponents caricature it.”
4.“Mainstream adopts a softened version.”
5.“It becomes obvious in hindsight.”
@davidsirota.com
@emmavigeland.bsky.social @kimdriscollma.bsky.social
Low density single-family-only zoning became a powerful property-value protection tool everywhere but today’s it has especially increased values in the places that pre existed the separated low density mistake that is Zoning, the 20th century’s Original Sin.
February 1, 2026 at 4:40 PM
Low density single-family-only zoning became a powerful property-value protection tool everywhere but today’s it has especially increased values in the places that pre existed the separated low density mistake that is Zoning, the 20th century’s Original Sin.
It also set the table for scarcity
Zoning built the foundation. It made car-dependence the legal default setting for most new growth.
February 1, 2026 at 2:14 PM
It also set the table for scarcity
Reposted by Safe Systems Civil Engineer
Land use, lower density and poverty are the main drivers of the spike in fatalities of people walking in the US "Pedestrian fatalities are moving away from downtowns (with a 63% decrease in study city downtowns) and now happening more in suburbs"Rodriguez and Fuerenchak 2023.
February 1, 2026 at 10:51 AM
Land use, lower density and poverty are the main drivers of the spike in fatalities of people walking in the US "Pedestrian fatalities are moving away from downtowns (with a 63% decrease in study city downtowns) and now happening more in suburbs"Rodriguez and Fuerenchak 2023.
From the OECD Affordable Housing Database (HM1.5, latest available):
Canada (2024): Detached 51.10%, Semi-detached 11.33%, Flats 36.18%
United States (2023, latest for U.S. in this table): Detached 62.74%, Semi-detached 6.11%, Flats 25.36%
@davidzipper
Canada (2024): Detached 51.10%, Semi-detached 11.33%, Flats 36.18%
United States (2023, latest for U.S. in this table): Detached 62.74%, Semi-detached 6.11%, Flats 25.36%
@davidzipper
February 1, 2026 at 1:48 AM
From the OECD Affordable Housing Database (HM1.5, latest available):
Canada (2024): Detached 51.10%, Semi-detached 11.33%, Flats 36.18%
United States (2023, latest for U.S. in this table): Detached 62.74%, Semi-detached 6.11%, Flats 25.36%
@davidzipper
Canada (2024): Detached 51.10%, Semi-detached 11.33%, Flats 36.18%
United States (2023, latest for U.S. in this table): Detached 62.74%, Semi-detached 6.11%, Flats 25.36%
@davidzipper
Let’s work our way #BackTo3. The only way it can happen is when states make much more zoning by right. ADUs. Single family home conversions. Duplex as the base unit at property owners choice. Over time multipliers could slowly fall to the 3:1 Silents and Boomers got in 1970.
My parents sold our house in 1975 for $45,000. Had it simply tracked inflation, it would be worth $275,000 today. Our biggest problem in a nutshell. #BackTo3
January 31, 2026 at 11:58 AM
Let’s work our way #BackTo3. The only way it can happen is when states make much more zoning by right. ADUs. Single family home conversions. Duplex as the base unit at property owners choice. Over time multipliers could slowly fall to the 3:1 Silents and Boomers got in 1970.
Above-inflation home prices growth came from two forces:
1. Supply blocked in high-demand metros
2. Bids boosted (more mortgage credit vs same incomes)
We turned housing into a wealth engine & kept supply tight creating permanent scarcity equity and collapsing affordability.
#BackTo3
1. Supply blocked in high-demand metros
2. Bids boosted (more mortgage credit vs same incomes)
We turned housing into a wealth engine & kept supply tight creating permanent scarcity equity and collapsing affordability.
#BackTo3
January 31, 2026 at 2:31 AM
Above-inflation home prices growth came from two forces:
1. Supply blocked in high-demand metros
2. Bids boosted (more mortgage credit vs same incomes)
We turned housing into a wealth engine & kept supply tight creating permanent scarcity equity and collapsing affordability.
#BackTo3
1. Supply blocked in high-demand metros
2. Bids boosted (more mortgage credit vs same incomes)
We turned housing into a wealth engine & kept supply tight creating permanent scarcity equity and collapsing affordability.
#BackTo3
Reposted by Safe Systems Civil Engineer
Massachusetts cities are "finding out" when it comes to ignoring the state's new TOD law. Rather than waste millions of taxpayer dollars in a quixotic fight, why not just build out a nice town center?
www.bostonglobe.com/2026/01/29/b...
www.bostonglobe.com/2026/01/29/b...
Campbell sues nine cities and towns for rebuffing state housing law - The Boston Globe
Attorney General Andrea Campbell filed the suit against Dracut, East Bridgewater, Halifax, Holden, Marblehead, Middleton, Tewksbury, Wilmington, and Winthrop.
www.bostonglobe.com
January 30, 2026 at 9:17 PM
Massachusetts cities are "finding out" when it comes to ignoring the state's new TOD law. Rather than waste millions of taxpayer dollars in a quixotic fight, why not just build out a nice town center?
www.bostonglobe.com/2026/01/29/b...
www.bostonglobe.com/2026/01/29/b...
Reposted by Safe Systems Civil Engineer
Zoning built the foundation. It made car-dependence the legal default setting for most new growth.
January 25, 2026 at 11:44 PM
Zoning built the foundation. It made car-dependence the legal default setting for most new growth.
Reposted by Safe Systems Civil Engineer
For each $1,000 drop in a census tract’s median income, fatal and severe pedestrian injuries rise by about 1.6%–2.0%.
x.com/_murphy_dan/...
x.com/_murphy_dan/...
X
X
x.com
January 25, 2026 at 6:29 PM
For each $1,000 drop in a census tract’s median income, fatal and severe pedestrian injuries rise by about 1.6%–2.0%.
x.com/_murphy_dan/...
x.com/_murphy_dan/...
Cities wanted highway-user revenues protected from being siphoned away, because diversion meant less money for streets/highways and more pressure back onto local property taxes.
January 27, 2026 at 3:47 AM
Cities wanted highway-user revenues protected from being siphoned away, because diversion meant less money for streets/highways and more pressure back onto local property taxes.
Euclid didn’t “create” gas taxes but it legalized the land-use pattern that made municipal street costs explode.
January 27, 2026 at 3:44 AM
Euclid didn’t “create” gas taxes but it legalized the land-use pattern that made municipal street costs explode.
After Euclid sanctioned single family zoning cities pushed to have key city corridors recognized as extensions “to and through municipalities” so state and federal programs could legally spend money on them.
January 27, 2026 at 3:41 AM
After Euclid sanctioned single family zoning cities pushed to have key city corridors recognized as extensions “to and through municipalities” so state and federal programs could legally spend money on them.
Reposted by Safe Systems Civil Engineer
Hear from report committee members about the potential of fiber-reinforced polymers, high- and ultra-high-performance concretes, and 3D-printed materials in dams, locks, and levees to improve strength, resilience, and cost-effectiveness.
Jan 27
1:00 - 2:30 PM (EST)
https://ow.ly/ju6850Y3PBT
Jan 27
1:00 - 2:30 PM (EST)
https://ow.ly/ju6850Y3PBT
Study on Furthering the Development and Use of Innovative Materials in Water Resources Infrastructure report release webinar
Dams, locks, and levees are critical to U.S. navigation, safety, and commerce—but many are reaching the end of or have surpassed their design lives. In response to a congressional request through the Water Resources Development Act of 2016, the Transportation Research Board of the National Academies of Sciences, Engineering, and Medicine examined how innovative materials could help the U.S. Army Corps of Engineers (USACE) maintain, repair, and modernize this vital infrastructure. Join this event to hear from committee members on the project resulting in TRB Special Report 359: Innovative...
ow.ly
January 26, 2026 at 5:05 PM
Hear from report committee members about the potential of fiber-reinforced polymers, high- and ultra-high-performance concretes, and 3D-printed materials in dams, locks, and levees to improve strength, resilience, and cost-effectiveness.
Jan 27
1:00 - 2:30 PM (EST)
https://ow.ly/ju6850Y3PBT
Jan 27
1:00 - 2:30 PM (EST)
https://ow.ly/ju6850Y3PBT
A very real safety issue we need to pay attention to. 1/2 of all ambulance calls there 2 years ago ….
High-speed two-wheelers* deter people from biking at all.
“Because of the dangers of those who are cycling fast, especially older people over 55 or 60 simply leave their bikes at home. We also hear that parents no longer dare to let their children cycle.”
*Not pedal-assist e-bikes
“Because of the dangers of those who are cycling fast, especially older people over 55 or 60 simply leave their bikes at home. We also hear that parents no longer dare to let their children cycle.”
*Not pedal-assist e-bikes
Amsterdam prepares to ‘ban the fatbikes’ amid rise in serious accidents
Experts say souped-up e-bikes pose big risk for children aged from 12 to 15, who account for many A&E cases
www.theguardian.com
January 26, 2026 at 4:46 PM
A very real safety issue we need to pay attention to. 1/2 of all ambulance calls there 2 years ago ….
U.S. land use generates more trip-making that defaults to cars, and our road funding/governance that defaults to the state builds and operates high-speed arterials to carry those trips, creating unusually high exposure and severity by land use design.
January 26, 2026 at 2:52 PM
U.S. land use generates more trip-making that defaults to cars, and our road funding/governance that defaults to the state builds and operates high-speed arterials to carry those trips, creating unusually high exposure and severity by land use design.
Stop with the groceries and gas.... It's much more about HOUSING and Health insurance, the bottom 1/2s biggest costs.
January 26, 2026 at 2:15 PM
Stop with the groceries and gas.... It's much more about HOUSING and Health insurance, the bottom 1/2s biggest costs.
Zoning built the foundation of car centrism in the US.
Zoning made car dependence the legal default setting for most new growth.
Zoning made car dependence the legal default setting for most new growth.
January 25, 2026 at 11:47 PM
Zoning built the foundation of car centrism in the US.
Zoning made car dependence the legal default setting for most new growth.
Zoning made car dependence the legal default setting for most new growth.