A sustainable city

[PatrickMc]

This is a plan for a sustainable city. Evidence suggests that less energy will be available to us in the future, which means that the energy-intensive suburban sprawl model which has dominated for the past 50 years is no longer sustainable. Even without energy constraints, urban sprawl no longer makes sense due to changing demographics (only 1/3rd of households are families with children). The technology to run cars on alternative fuels is not available at the scale required to keep urban sprawl running. If the world's cities continue to sprawl there is a danger that by the year 2050 when world population has reached 11 billion that all of the forests on earth will have disappeared. For all of these reasons, the only option left to us is to stop the horizontal expansion of our cities and to create more compact cities that do not rely on automobiles for transportation. The planet cannot sustain a detached house for every family and two cars in the garage, but sustainable cities can be built that can provide a higher standard of living for everyone.

What follows is a plan for a sustainable, compact city. I would be interested in anyone's thoughts, comments, or suggestions.


The Sustainable City:

-The city does not exceed 0.65 square miles for a population of 10,000. 6.5 square miles for 100,000. 65 square miles for 1 million, 650 square miles for 10 million, etc.

-Minimum residential density of 20 units per acre (15,000-16,000 people per square mile) The typical American suburb is 4 to 5 units per acre or 3,000-4,000 people per sq. mi. The density must be an average of 20 units per acre for the area within 1/2 mile of a mass transit stop. Due to the high density, most housing would be in apartment buildings. There would be few if any single-family homes, and these would be reserved for families with children.

-Every building in the city is no more than 1/2 mile from a transit stop. 1/2 mile is equal to a 10 minute walk at a comfortable pace. Some cities may wish to reduce the maximum distance from a transit stop to 1/4 mile, but this requires a higher minimum density.

-Commercial and public services are located adjacent to the mass transit stop. Each transit stop functions as a neighborhood center. There is a sufficient range of services at the center to meet all of a household's weekly needs

-Mixed-use buildings are permitted in or near the mass transit stop/neighborhood center

-Maximum building height of 6 stories. For the same size population, mid-rise buildings consume less energy than high-rises. The exception to this rule would be cities that do not have sufficient space to house their population in 6 story buildings.

-There are no surface parking lots. Parking is on-street adjacent to the curb and in garages. There are no off-street parking requirements. With everything in the city within walking distance of one's home, car trips would be greatly reduced making off-street parking unecessary and a wasteful use of space.

-Maximum street width of 26 ft (4 lanes). This is so that pedestrians can easily cross the street at any point. Also, vehicle speeds tend to exceed 30 mph on roads wider than 26 ft. Above 30 mph, a pedestrian's chance of survival if hit by a car is less than 50%.

-Streets are built in a modified grid pattern for ease of navigation. The grid may be modified to suit the terrain. This is so that it is easy to walk from one point to another within the city.

-Buildings are 10-40 ft from the street. Residential buildings might be set further back so that there is more space for grass, trees, and shrubs. Commercial buildings would be closer to the street as this has been shown to draw people into the store, and creates a stimulating streetscape to look at while walking (as opposed to acres of surface parking fronting the road).

-If there are multiple buildings fronting the same street, a building must share a setback with at least one adjacent building. This is so that buildings are not randomly scattered on a block.

-Trees are planted in or adjacent to the sidewalk for shade. This is especially important in hot climates.

-50% of the city's ground space is dedicated to parks/landscaping.

-Food may be grown in vertical farms where necessary. These have the advantage of not being affected by weather so crop yields would always be optimal. Since they are located in the cities themselves, the energy used in transportation would be eliminated, reducing costs and pollution. Vertical farms would be no taller than the rest of the structures in a city so they would blend seamlessly into the urban environment - in a typical compact city they would be no more than 6 stories tall.

-Each neighborhood would be allowed to draft its own plan. The only requirement is that the plan must fulfill the requirements of the compact city as outlined.

[Tide]

As I recently read in New Urban News a quote which said. "Would you want your marriage to be just sustainable? Why then do we accept sustainable cities?"

I like your ideas, but what could you do more to make it more than sustainable, such as; where does everyone work and those businesses must too be eco/neighborhood friendly, etc. etc.

[PatrickMc]

Tide,

Businesses are located near the mass transit stop, which functions as the neighborhood center. Factories and polluting businesses would be located outside the city but still within an easy distance to be covered by mass transit in less than 10 minutes.

The article I've written is a set of rules that a sustainable city should follow. Mainly it is a set of regulations on the physical form to ensure that walking and mass transit are viable transportation options. I have tried to create the simplest set of rules needed to create the desired result. As far as what type of work would be done, that would depend on the location and population of the city.

I think that article is referring to the intangible qualities a city has that attracts people to it. That is something that can partially be achieved through good planning, but mainly it is something that has to evolve over time and develop on its own.

Thank you for your reply.

[DetroitPlanner]

In general, its a good concept, but I can see a lot of room for refinement.

I would think at those densities that transit should be much closer than 1 Mile. Note that when you get into CBDs Transit will be on darn near every street.

Your roads would be much safer with 12 foot wide lanes and in most cases 3 lanes can handle traffic better than 4. 6.5 foot lanes would not hold delivery trucks. If you have any ports or heavy industries these streets would be inadaquete as truchs would not be able to even turn.

Have you looked into the amount of sun for your vertical gardens? With 20 units per acre you're talking some serious shadows due to tall buildings.

Allowing neighborhoods to draft their own plans could be a problem without someone coordinating them. You could end up with comptition between neighborhoods for landuses that are wholly inappropriate. What do you do if every neighborhood wants a Football Stadium or be the downtown? Build 20 of them? Where would the NIMBYs go? How can you set residential more than 40' back from the street and still get 40 du per acre?

Have you looked at LeCourbousier's Plan or FLlW's Broadacre City?

[jkbrown]

So, for a density comparison, you are looking at a place that is as dense as Hong Kong or Singapore?

And if 50% of your space is open space, doesn't that make your net density 30,000 per square mile?

[Cardinal]

It is not sustainable if a majority of people do not want to live there. Only a minority of people would choose to live in six story buildings packed into a small area.

[HeartlandCityBoy]

Hmm are you so sure cardinal? Because the vast majority of the United States hasn't yet experienced a "true" city.

[Plan-it]

It is not sustainable if a majority of people do not want to live there. Only a minority of people would choose to live in six story buildings packed into a small area.

I agree Cardinal. This would only be applicable to a subset of the population.

People want choice in their built environment and those choices change over time as people age and new generations come of age. Some of that choice should be environments as you had explained, but to have a true sustainable city, you will need to incorporate various housing types into the sustainable frame work. Unless we move to a completly socialist form of government (which I am not advocating) people with wealth will want to find ways to differentiate themselves from the masses. It has happened throughout history. Your framework will need to account for these types of variables if you want something more than a utopian dream.

[PatrickMc]

JKBrown,

Believe it or not, a density of 15,000 per sq mile can be achieved while leaving 50% of the area as open space. There are 640 acres in a square mile. If you build 5 story buildings with a density of 40 units/acre than you only need 320 acres to get a density of above 16,000/sq mi. Hong Kong and Singapore are both much higher density than this. 15,000 per sq mile is comparable to Stockholm or Copenhagen. Both Hong Kong and Singapore lack green space, so the comparison doesn't fit at all. Most sprawling cities have much less than 50% of their ground area dedicated to green space, so the city I've described would have more green space than your typical suburb.

You should look at the plans for Dongtan, Masdar, and Hammarby Sjostad.

It's besides the point anyway. It would be very nice for everyone on the planet to have one acre of land to themselves and two cars to transport them everywhere, but this is not possible. The sustainable city is about creating a city which is in line with what reality can reasonably offer us.

[Gedunker]

PatrickMc -- welcome to Cyburbia. Please understand that our rules do not permit cross-posting threads. I have moved the identical thread you started in the Envirnmental Planning subforum and merged it to this thread. If, in the future, you are unsure where to place a thread, feel free to contact an admin or mod and we'll be happy to help you. Thank you and carry on!

[Tide]

Tide,

Businesses are located near the mass transit stop, which functions as the neighborhood center. Factories and polluting businesses would be located outside the city but still within an easy distance to be covered by mass transit in less than 10 minutes.

But in the holistic view of sustainable cities the businesses and factories are part of that vision. Polluting factories are NOT in a vision of a sustainable city. Also, depending on the climate is this city electric powered or gas/oil heat?

Also, your road plans. Is every road constructed the same? Are they all through streets? You mention goods delivery, I would expect that the more commercial roads to be a bit wider than the residential streets, no?

[PatrickMc]

In general, its a good concept, but I can see a lot of room for refinement.

I would think at those densities that transit should be much closer than 1 Mile. Note that when you get into CBDs Transit will be on darn near every street.

Well, if you look at the plan I wrote the maximum distance from a transit station is 1/2 mile. In some cities this could be reduced to 1/4 mile, but this requires a higher population density.

Your roads would be much safer with 12 foot wide lanes and in most cases 3 lanes can handle traffic better than 4. 6.5 foot lanes would not hold delivery trucks. If you have any ports or heavy industries these streets would be inadaquete as truchs would not be able to even turn.

Delivery would be handled by the small trucks you see in Japan and Europe. I see no reason why we cannot use these here, and have smaller parcel deliveries. This would work well since the source of production would be located close to where these items were consumed (such as with food). I agree that in some cases 3 lanes is better. 4 lanes/26 ft would be the maximum street width since this has been shown to be the safest street width for pedestrians, in addition to creating pleasing human-scale streets which can be completely shaded by trees planted adjacent to the curb.

Another option for delivery would be freight trams, such as the ones being used in Amsterdam.

Have you looked into the amount of sun for your vertical gardens? With 20 units per acre you're talking some serious shadows due to tall buildings.

The beauty of vertical farms is that they are completely self-contained. Sunlight isn't required at all. They have already achieved quite high yields - 100 times per unit of land - with experimental vertical farms. Vietnam and Japan are making huge strides with this technology. The downside is the amount of energy required to run these things, but the peaking of world oil supply means that conventional farming methods will soon become more expensive, making this technology commercially viable. Renewable energy would be used to power the farms.

Allowing neighborhoods to draft their own plans could be a problem without someone coordinating them. You could end up with comptition between neighborhoods for landuses that are wholly inappropriate. What do you do if every neighborhood wants a Football Stadium or be the downtown? Build 20 of them? Where would the NIMBYs go? How can you set residential more than 40' back from the street and still get 40 du per acre?

Obviously there would need to be some coordination among the neighborhoods which would have to be the city government. The placement of stadiums and such would be handled much in the same way as it is today. Neighborhoods are allowed to decide where they want the high density to go, where they want the low density, what kind of businesses to allow in the neighborhood center, etc. No building in the city is more than 40' from the street.

Have you looked at LeCourbousier's Plan or FLlW's Broadacre City?

Yes, I have studied both of those. Both are failures and could never work. FLW proposed service clusters spaced out at 1 mile intervals, but Broadacre city had such a low density that this was impossible. The Radiant City is just ridiculous as it crams people into a small space just because we can. Why do you bring these up?

It is not sustainable if a majority of people do not want to live there. Only a minority of people would choose to live in six story buildings packed into a small area.

Well, I have said that there would be space available for the construction of single-family homes. These could be as large as people wanted. The neighborhood is required to draft a plan with a net density of 20 units per acre. If they wanted they could build 50% of the houses as 1 unit per acre, and 50% as 40 units per acre. This is something the neighborhood has to decide. Remember that families with children are less than 1/3rd of all households, and this demographic is shrinking.

Also, you should look at the European cities which are composed of six story buildings "packed into a small area". These cities are considered to be the most livable in the world (Paris, Venice, etc). Americans routinely escape their suburbs for these cities, marvel at them for two weeks, than return to their auto-dominated 'burbs where they fight to preserve the status quo. It is a strange sort of hypocrisy that has developed.

Thanks for all the feedback.

But in the holistic view of sustainable cities the businesses and factories are part of that vision. Polluting factories are NOT in a vision of a sustainable city. Also, depending on the climate is this city electric powered or gas/oil heat?

If you are building an entire city from scratch than you would have to figure out what businesses would be there from the start. But if you create a set of guidelines and let the city grow over time, than these things work themselves out naturally. You are right, eventually the sustainable city would be completely powered with renewable energy sources, whichever was most appropriate for the location of the city. Factories might eventually be located in the city themselves if they are able to completely eliminate waste and pollution (this would include noise pollution). To build solar panels, you have to use a dirty coal-powered factory. A sustainable city might not be completely powered with renewables from the start, but would steadily progress toward that goal.

It's important to remember that the sustainable city isn't something that you plop down onto the ground in finished form. It grows over time to respond to the changing needs of the population/changing circumstances.

I understand that the type of Industry is very important in creating a sustainable city. If you took a city with the same unsustainable industries, but one was a typical autombile-based city while the other was a walkable, transit-oriented city, than the walkable/transit oriented one will consume less energy. All things being equal, a walking/transit city will be more energy efficient (and thus more sustainable) than a driving city.

[HarryFossettsHat]

The Sustainable City:

-The city does not exceed 0.65 square miles for a population of 10,000. 6.5 square miles for 100,000. 65 square miles for 1 million, 650 square miles for 10 million, etc.

- Minimum residential density of 20 units per acre (15,000-16,000 people per square mile) The typical American suburb is 4 to 5 units per acre or 3,000-4,000 people per sq. mi. The density must be an average of 20 units per acre for the area within 1/2 mile of a mass transit stop. Due to the high density, most housing would be in apartment buildings. There would be few if any single-family homes, and these would be reserved for families with children.

- Every building in the city is no more than 1/2 mile from a transit stop. 1/2 mile is equal to a 10 minute walk at a comfortable pace. Some cities may wish to reduce the maximum distance from a transit stop to 1/4 mile, but this requires a higher minimum density.

- Commercial and public services are located adjacent to the mass transit stop. Each transit stop functions as a neighborhood center. There is a sufficient range of services at the center to meet all of a household's weekly needs

- Mixed-use buildings are permitted in or near the mass transit stop/neighborhood center

- Maximum building height of 6 stories. For the same size population, mid-rise buildings consume less energy than high-rises. The exception to this rule would be cities that do not have sufficient space to house their population in 6 story buildings.

- There are no surface parking lots. Parking is on-street adjacent to the curb and in garages. There are no off-street parking requirements. With everything in the city within walking distance of one's home, car trips would be greatly reduced making off-street parking unecessary and a wasteful use of space.

- Maximum street width of 26 ft (4 lanes). This is so that pedestrians can easily cross the street at any point. Also, vehicle speeds tend to exceed 30 mph on roads wider than 26 ft. Above 30 mph, a pedestrian's chance of survival if hit by a car is less than 50%.

- Streets are built in a modified grid pattern for ease of navigation. The grid may be modified to suit the terrain. This is so that it is easy to walk from one point to another within the city.

- Buildings are 10-40 ft from the street. Residential buildings might be set further back so that there is more space for grass, trees, and shrubs. Commercial buildings would be closer to the street as this has been shown to draw people into the store, and creates a stimulating streetscape to look at while walking (as opposed to acres of surface parking fronting the road).

- If there are multiple buildings fronting the same street, a building must share a setback with at least one adjacent building. This is so that buildings are not randomly scattered on a block.

- Trees are planted in or adjacent to the sidewalk for shade. This is especially important in hot climates.

- 50% of the city's ground space is dedicated to parks/landscaping.

- Food may be grown in vertical farms where necessary. These have the advantage of not being affected by weather so crop yields would always be optimal. Since they are located in the cities themselves, the energy used in transportation would be eliminated, reducing costs and pollution. Vertical farms would be no taller than the rest of the structures in a city so they would blend seamlessly into the urban environment - in a typical compact city they would be no more than 6 stories tall.

- Each neighborhood would be allowed to draft its own plan. The only requirement is that the plan must fulfill the requirements of the compact city as outlined.

20 units an acre...about 40/50 per hectare. The UK already has a minimum residential density of 30 dwellings per hectare, 35 dwellings per hectare is very common in development proposals located in suburban settings (14.5 dwellings per acre), and these are still often semi-detached/short terrace/detached units. Your targets are not too far-fetched, and maybe not high/ambitious enough.

[PatrickMc]

Thank you, HarryFossettsHat, for pointing that out. I didn't know that about UK development - thanks for the info.

Sustainable cities have been proposed with much higher densities. I opted to go with the lowest density required to support the mass transit system and neighborhood centers. This way you can reduce the "shock" to Americans who are used to low-density, automobile-oriented living. This is also why I have dedicated so much of the ground area to green space/landscaping, to try to maintain some of that suburban feel.

[Tide]

http://www.wired.com/science/planete...heresies_intro

This is a great article in June's Wired Magazine. It speaks more of global warming but aren't those same mantras part of the sustainable city movement. Infact one of the 10 radical ideas is living in cities and why, check it out it's a quick and interesting read.

[CJC]

Thank you, HarryFossettsHat, for pointing that out. I didn't know that about UK development - thanks for the info.

Sustainable cities have been proposed with much higher densities. I opted to go with the lowest density required to support the mass transit system and neighborhood centers. This way you can reduce the "shock" to Americans who are used to low-density, automobile-oriented living. This is also why I have dedicated so much of the ground area to green space/landscaping, to try to maintain some of that suburban feel.

I was going to agree with HFH - 20 per acre is actually quite low.

Also, as a frame of reference for Americans - San Francisco is just under 17,000 ppsm (just over the number you're looking for) with the vast majority of the city being only 2-3 stories (and plenty of single family homes - they just aren't detached). SF also manages to have the second highest percentage of land devoted to parkspace in the US, after NYC.

[DetroitPlanner]

I brought up those two plans because they were highly thought of at the time they were developed but nothing like those have ever been developed. The closest things to Le Courbousier could be seen in Edge Cities, but instead of sitting in parks, the towers sit in parking lots.

I would like to know how you can have farms without photosynthisis. Can you provide a link?.

Japanese and european ports need to move frieght both to and from the boat. You can't move freight on the roads you propose. Roads of this width would have serious turning radii problems, even for smaller trucks. You are also setting up your roads for numerous sideswipe incidents and you could not even fit or turn a bus on a road of those widths. To build roads with these known problems you would have a lot of liability issues. For example, how could bicyclists use 28 foot wide four lane roads? Can you get FHWA and AASHTO to change their standards (based on evidence that your roads are safer?) Have you thought about rail? Rail is not the most sustainable option in most applications, if it was you would see a lot more of it and a lot fewer rails to trails projects. Business people are not stupid, they want to be able to ship things for the lowst transport costs period. You need to move frieght in order for your community to flourish. Just look at what has happened with Detroit once it had to compete with the rest of the world for manufacturing. Job sustainablity relies on trade. What are your communities exports or imports? Can you export your veggies? How will your goods get on the smaller trucks? You will need a distrbution center for that, and in order for that you need to address freight.

Most of Detroit has a 1/4 mile walking distance to transit and its a lot less dense that what you propose.

Are we talking a city wide d.u. number or is this just in residential areas? You will need space for parks, industries, retail, transportation, utilities....

[PatrickMc]

http://www.wired.com/science/planete...heresies_intro

This is a great article in June's Wired Magazine. It speaks more of global warming but aren't those same mantras part of the sustainable city movement. Infact one of the 10 radical ideas is living in cities and why, check it out it's a quick and interesting read.

Thanks, Tide. I have already read that article. It is very good.

I would like to know how you can have farms without photosynthisis. Can you provide a link?.

All you need is UV light which can be produced with UV bulbs. UV bulbs have been around since the 1920s. Yields are many times higher and of much higher quality with indoor farms because you can completely control everything that is happening to the plant.

http://en.wikipedia.org/wiki/Vertical_farming

http://en.wikipedia.org/wiki/Hydroponics

Japanese and european ports need to move frieght both to and from the boat. You can't move freight on the roads you propose. Roads of this width would have serious turning radii problems, even for smaller trucks. You are also setting up your roads for numerous sideswipe incidents and you could not even fit or turn a bus on a road of those widths. To build roads with these known problems you would have a lot of liability issues. For example, how could bicyclists use 28 foot wide four lane roads? Can you get FHWA and AASHTO to change their standards (based on evidence that your roads are safer?) Have you thought about rail? Rail is not the most sustainable option in most applications, if it was you would see a lot more of it and a lot fewer rails to trails projects. Business people are not stupid, they want to be able to ship things for the lowst transport costs period. You need to move frieght in order for your community to flourish. Just look at what has happened with Detroit once it had to compete with the rest of the world for manufacturing. Job sustainablity relies on trade. What are your communities exports or imports? Can you export your veggies? How will your goods get on the smaller trucks? You will need a distrbution center for that, and in order for that you need to address freight.

Have you seen Amsterdam or Venice? Both cities have to move huge amounts of freight every day, yet 98% of the streets are less than 26 ft wide. They accomplish this by using smaller trucks and freight trams. Have you thought about peak oil? This is going to rapidly change the definition of what is sustainable - expect to see a lot more rails and a lot fewer cars. I think you are overestimating the danger to cyclists and pedestrians, since the majority of trips would be by walking and cycling (car traffic would be minimal). If the road was 4 lanes, 26 ft wide, you could say that the right lane is reserved for cyclists at all times, but may be used by cars if no cyclists are present. This is what they do in China and it works. Have you heard of the naked streets movement? In Europe they have successfully reduced vehicle speed, injuries to pedestrians, and accidents by having narrow streets that lack markings/lanes. The reason for this is simple: without a set of readily identifiable rules governing the space, people are required to slow down and actively pay attention to what's going on around them. The evidence speaks for itself and the method works.

http://www.walkablestreets.com/safer.htm

http://www.carfree.com/freight.html

http://www.eta.co.uk/More-naked-stre...ain/node/11183

Most of Detroit has a 1/4 mile walking distance to transit and its a lot less dense that what you propose.

Yes, and I believe the waiting time between buses is much longer than 10 minutes. I should add that in the sustainable city, the maximum waiting time between buses/trains would be 10 minutes, 5 minutes during peak hours. With higher densities the frequency is even greater.

http://www.sierraclub.org/sprawl/art...cteristics.asp

Are we talking a city wide d.u. number or is this just in residential areas? You will need space for parks, industries, retail, transportation, utilities....

20 units/acre is for the area within 1/2 mile radius of a transit stop, as described in the plan. Park space has been accounted for, as has space needed for roads. Retail is located in the neighborhood centers, which are built around the transit stops. Non-polluting industry may also be found in the neighborhood center, with noxious uses located a minimum safe distance away from a residential area (outside of the city if need be).

[jkbrown]

My mistake on the population. The WorldBook 2004, the latest I could find, listed Singapore and Hong Kong as the cities having over 15,000 PPM. And I didn't look at Census info.

You have done your homework. Your answers are thoughtful, and good natured. *0)

Your neighborhood plans can be framed by a Citywide Master Plan that the individual plans have to be found in conformance with, and with each other, to provide a cohesive group of plans.

Be wary of your commercial in this conceptual plan. Some of the TOD's I've visited in California way over estimated the amount of commercial space, and now have a majority of empty shop fronts.

[DetroitPlanner]

I hope that you can tell by my questioning that I am playing devils advocate here.

So with vertical farms we're not talking about using solar energy and terraces, correct? Would not using solar be more sustainable? Call me old fashioned, but I don't think I'd like food grown indoors, but then again.. I like sprouts.....

I know I'm going to sound like an engineer, but I think you're asking for problems with streets that narrow. I've been to europe and they have a heck of a time moving freight or busses. They do however have by-pass roads that you might want to consider, but those also tend to suck businesses from the core making your city less sustainable.

I'm not so worried about peak oil. I've seen some pretty phemonenal technology that has been implemented in the past several years and know of lots of new projects in the works. I am concerned about how sustainable transportation is however in terms of how we currently price it, allocate funds, and the quickly depleting resouorces for it (the gas tax revenues shrink every year but the demand for transit and road infrastructure grows, both use the gas tax as a major revenue source).

[wahday]

...Hong Kong and Singapore are both much higher density than this. 15,000 per sq mile is comparable to Stockholm or Copenhagen....

I'm not sure where you are figuring this from. Stockholm is at about 7024ppl/sq. mi. (2700ppl/sq. km). Copenhagen is only 4813ppl/sq. mi. (1850ppl/sq. km). In your calculations, you also need to allow for streets and rights of way (alleys and the like). This reduces your buildable area quite a bit. Indeed, the struggle between offering a tighter street grid, which promotes mobility, is often offset by the reduction in buildable land that requires higher density on that land. Not that it can't be done, but it requires that what is on that private land be even more dense.

I still think 15k/sq. mi. is doable. Manhattan is a whopping 66,940ppl/sq. mile, so I think less than a quarter of that density is manageable while maintaining a positive quality of life for residents. San Francisco is a comparable example at 16,380ppl/sq. mile.

This is an interesting discussion, though. This all seems premised on the idea of building a new city from scratch. Obviously, this is happening a lot in places like China, but I am personally more intrigued by the challenge of reconfiguring our existing cities to be more efficient and I look to the work of Jaime Lerner as to what can be accomplished on small budgets that emphasize low impact and economically sustainable solutions (which are often sustainable in other ways as well) for existing urban centers.

[CJC]

All you need is UV light which can be produced with UV bulbs. UV bulbs have been around since the 1920s. Yields are many times higher and of much higher quality with indoor farms because you can completely control everything that is happening to the plant.

http://en.wikipedia.org/wiki/Vertical_farming

http://en.wikipedia.org/wiki/Hydroponics

It is worth noting that "vertical farms" have only been seriously suggested for fruits and veggies that cannot be grown locally with ease. Staples like rice, wheat, or corn won't work because of the massive amount needed (and thus the massive size of the vertical farm needed).

Furthermore, in places like northern California or southern Europe (or any place within a couple thousand miles by rail) with year-round growing seasons and fertile soil, it is always going to be more sustainable to get fruits and veggies from the farmland. Even in places further away, I doubt many of the "sustainability" claims of vertical farms. Soooooo much energy and resources are used to build the farm, light the UV lights, pump in the water, bring in the fertilizer, etc. I think a much better (and more sustainable) idea is to invest in electrifying our railroads and linking farms and cities to those electrified railways. This would help not only your brand new city, but all existing cities as well.

[PatrickMc]

My mistake on the population. The WorldBook 2004, the latest I could find, listed Singapore and Hong Kong as the cities having over 15,000 PPM. And I didn't look at Census info.

That seems low to me. I've read that some of the Hutong neighborhoods in China can have densities exceeding 120,000/sq. mi.

You have done your homework. Your answers are thoughtful, and good natured. *0)

Your neighborhood plans can be framed by a Citywide Master Plan that the individual plans have to be found in conformance with, and with each other, to provide a cohesive group of plans.

Yes, that sounds like a more precise wording of what I was intending to say.

Be wary of your commercial in this conceptual plan. Some of the TOD's I've visited in California way over estimated the amount of commercial space, and now have a majority of empty shop fronts.

Very true. Here is a graph showing retail space per capita for various countries:

http://www.oftwominds.com/photos07/retail-sq-ft.png

I'm still working on what the ideal amount of space for retail would be in the neighborhood center. 10 sq. ft. per person would come out to 160,000 sq. ft. of retail in a neighborhood center serving a population of 16,000. Bear in mind there is another 160,000 sq. ft. of retail 1 mile away in each direction. 5 sq. ft. per person might be sufficient.


DetroitPlanner:

I hope that you can tell by my questioning that I am playing devils advocate here.

So with vertical farms we're not talking about using solar energy and terraces, correct? Would not using solar be more sustainable? Call me old fashioned, but I don't think I'd like food grown indoors, but then again.. I like sprouts.....

I understand that you're playing devil's advocate. No hard feelings. Vertical farms would only be used in cities that had insufficient farmland to feed their populations. Most or all of the food is grown within a 200 mile radius of the city to reduce the fuel used in transportation. You may have heard the phrase "the era of the 2,000 mile salad is over".

The quality of food produced in vertical farms is many times higher. With hydroponics you just have the plant in a nutrient solution that contains everything the plant needs. The plant is bathed in UV light which is timed to maximize growth. Pests are eliminated because there is no soil, and if any turn up they are quickly destroyed by adjusting the nutrient solution, or they are prevented from growing in the first place by the nutrient solution. The weather doesn't affect anything so crops can't be wiped out by drought or flood. There are many advantages.

I think vertical farms could eventually be completely powered with whatever local renewable energy sources were available, be it solar, wind, geothermal, or whatever. They might even provide some of their own power by burning the waste products in the building itself.

This reminds me of another feature that a sustainable city might have that I neglected to mention: In Hammarby Sjostad, instead of having a conventional sewer system, waste is collected in a series of tubes and then burned in a power plant to provide energy. When it comes to renewable energy, every little bit helps, and this technology could provide a significant source of power for cities.

I know I'm going to sound like an engineer, but I think you're asking for problems with streets that narrow. I've been to europe and they have a heck of a time moving freight or busses. They do however have by-pass roads that you might want to consider, but those also tend to suck businesses from the core making your city less sustainable.

I think the problem of moving freight on small streets is not insurmountable. The real problem is turning right, which can be solved if the vehicle moves to the far left before turning right. Track can be laid accordingly. Since food is produced locally, the size of deliveries doesn't need to be as large for it to make economic sense. Since deliveries needn't be as large, smaller vehicles can be used to make the deliveries. I suppose if it is absolutely necessary, you could have grade separated roads for trucks which would connect to the distribution center. These would be above or below ground and would connect to the main distribution center. The distribution center would have normal roads connecting to it, with freight trams and smaller trucks distributing the goods throughout the city. I see no reason why all freight can't eventually be moved to rail, but perhaps I am underestimating the problem. All I know is that cities functioned fine without wide roads and large trucks before they were invented, so I see no reason why they can't be made to work again in the same way.

I'm not so worried about peak oil. I've seen some pretty phemonenal technology that has been implemented in the past several years and know of lots of new projects in the works. I am concerned about how sustainable transportation is however in terms of how we currently price it, allocate funds, and the quickly depleting resouorces for it (the gas tax revenues shrink every year but the demand for transit and road infrastructure grows, both use the gas tax as a major revenue source).

The technology to replace oil has been greatly over-hyped in my opinion. At the very least, this technology is not available at the scale needed to maintain the one-car per person paradigm that has been the norm in this country for the past 60-70 years or so. This means that we need to find other ways of getting around, which is one of the primary goals of the sustainable city plan that I have designed.

The reason for this over-hyping? In my opinion there is a lot of money in research grants, and in marketing snake oil.

http://www.technocracy.ca/pdfs/Why-N...ls-indexed.pdf

I'm not sure where you are figuring this from. Stockholm is at about 7024ppl/sq. mi. (2700ppl/sq. km). Copenhagen is only 4813ppl/sq. mi. (1850ppl/sq. km). In your calculations, you also need to allow for streets and rights of way (alleys and the like). This reduces your buildable area quite a bit. Indeed, the struggle between offering a tighter street grid, which promotes mobility, is often offset by the reduction in buildable land that requires higher density on that land. Not that it can't be done, but it requires that what is on that private land be even more dense.

It seems my numbers there regarding population density are a bit off. I was looking at something which was referring to residential density in the city center. So the centers of Stockholm and Copenhagen apparently have around 15,000.

I have considered space for streets and alleys. It seems to me that the amount of space needed for streets and alleys is roughly the same regardless of whether you have 5 units per acre or 20 units per acre (assuming you are building a grid with alleys down the center of the block). This factor has been considered in my calculations.

I still think 15k/sq. mi. is doable. Manhattan is a whopping 66,940ppl/sq. mile, so I think less than a quarter of that density is manageable while maintaining a positive quality of life for residents. San Francisco is a comparable example at 16,380ppl/sq. mile.

Well, San Fransisco is a much more favorable comparison than Hong Kong or Singapore.

The challenge was finding the ideal density - enough people to support all the goods and services needed by a community within a small area so that they can be walked to, but still enough space so as to not feel overcrowded.

This is an interesting discussion, though. This all seems premised on the idea of building a new city from scratch. Obviously, this is happening a lot in places like China, but I am personally more intrigued by the challenge of reconfiguring our existing cities to be more efficient and I look to the work of Jaime Lerner as to what can be accomplished on small budgets that emphasize low impact and economically sustainable solutions (which are often sustainable in other ways as well) for existing urban centers.

The sustainable city master plan could be used as a guidebook for creating new neighborhood plans, so it can be used incrementally. It isn't something that necessarily has to be plopped down on the ground in finished form.

It is worth noting that "vertical farms" have only been seriously suggested for fruits and veggies that cannot be grown locally with ease. Staples like rice, wheat, or corn won't work because of the massive amount needed (and thus the massive size of the vertical farm needed).

Furthermore, in places like northern California or southern Europe (or any place within a couple thousand miles by rail) with year-round growing seasons and fertile soil, it is always going to be more sustainable to get fruits and veggies from the farmland. Even in places further away, I doubt many of the "sustainability" claims of vertical farms. Soooooo much energy and resources are used to build the farm, light the UV lights, pump in the water, bring in the fertilizer, etc. I think a much better (and more sustainable) idea is to invest in electrifying our railroads and linking farms and cities to those electrified railways. This would help not only your brand new city, but all existing cities as well.

A very good idea. I have said that vertical farms would only be used in areas lacking sufficient farmland to grow their food, but perhaps I should add a line to my article clarifying this. Good idea about linking to local farming towns, I had always envisioned this too but neglected to mention it in my plan.

[CJC]

Have you thought about using more of a Curitiba-style of development? That is, more 20-30 story buildings on transit lines, quickly scaling down to as low as single story buildings before scaling back up where the next transit line is. I realize that for the building itself, 5-8 stories is optimum, but much taller buildings closer in allows for more efficient use of the transit system and retail areas - so I'm wondering if it is better to have a more "sustainable" set of buildings, or a more "sustainable" transit system and retail network.

[PatrickMc]

Have you thought about using more of a Curitiba-style of development? That is, more 20-30 story buildings on transit lines, quickly scaling down to as low as single story buildings before scaling back up where the next transit line is. I realize that for the building itself, 5-8 stories is optimum, but much taller buildings closer in allows for more efficient use of the transit system and retail areas - so I'm wondering if it is better to have a more "sustainable" set of buildings, or a more "sustainable" transit system and retail network.

I don't like overly tall buildings for a few reasons. Buildings in excess of 8 stories violate the human scale. A person above 8 stories has almost no connection to the street, whereas at 6 stories a mother can easily identify her child if s/he is playing in the courtyard below. Energy use and maintenance costs tend to rise the higher you build, so that the energy savings from increased density is somewhat negated. From what I've read, you only need 20 units/acre average within 1/2 mile radius to support a transit station with frequent service (10 minute maximum headways). It doesn't really matter what the range is so long as the average is 20/acre. So I'm not sure that placing these really tall buildings adjacent to the transit stations is necessary, and I feel that they would disrupt the character of neighborhoods. I think one of the reasons they did this in Curitiba is because they needed to increase density but didn't want to demolish the historic low-rise neighborhoods in the city. This isn't really a problem in America as most suburbs are so generic as to not be worth preserving. Many suburbs such as those built immediately after WWII are composed of temporary structures that were intended to be torn down all along. No one planned for them to still be standing 60 years later.

High-rise construction could be used, but I feel it should be avoided if possible. Increased energy costs will make high-rises even more difficult to build and operate in the future, and the negative social effects of high-rises have been written about extensively.