Monday, June 27, 2011

Triangle City

In the comments to my post on grids, Charlie over at Old Urbanist suggested that I create a physical representation of my ideal city from scratch.
Protip: Click on it to make it bigger.
Well, here it is. Carved out of the South Jersey backwoods, Triangle City is the hypothetical conversion of a bunch of farms into a small city of about 30,000. It is done via several design techniques:

1. Street hierarchy. ...Wait? Yep, street hierarchy. Yes, that bane of the suburbs makes an appearance here. The reason is that it's not the hierarchy that makes suburban streets so darn wide, it's the prescribed width of the streets. Here, the hierarchy is:
(a) Intercity highways. Complete streets about 75 feet wide. These are the roads which connect Triangle City to other towns and cities.
(b) Through-roads. Complete streets, or bike-sharrowed streets, about 30 feet wide. These are the arteries of the city.
(c) Local streets. Naked streets, 15 to 20 feet wide.These are the streets that actually go past most addresses.
Unlike autocentric suburban hierarchies, however, this one assumes connectivity. The reason why residential streets stay quiet is because they're so narrow hardly anyone'd think to use them. Pedestrian connectivity, however, is quite strong, since these roads normally interconnect between various parcels.

2. Reserved park and civic space. Three major reserved spaces show on the plan. The central one is Center Park (duh), a large reserved centerpiece civic park, of the type most communities this size lack. The funky-shaped one southeast of it is Civic Square, reserved for governmental buildings (think City Hall). Finally, the long linear park along the northern edge is the nature preserve, Forest Park. Within each neighborhood in this city, however, at least one (1) public park about a block in size and one (1) public playground, same size, is required in the development plan.

3. Reserved space for prime properties. Prior to releasing the land for development, the City will also reserve chief parcels (wonky corners, hilltops, etc.) for prime civic buildings--schools and libraries--and a plot, pursuant to a prior location plan, for combined police and fire stations. Three civic health centers would also be placed.

4. Gridlike Grid. As I noted in my previous post on the topic, the best way to design a grid is to modify it. By using laneways and a few other tricks, the otherwise-strong grid of the city is modified enough to create place and interest.

5. Urban Density. The average density would be about that shown in this post, where wealthier neighborhoods would use this model as single-family detached and less wealthy ones twins or four- to six-unit apartments. This is a density similar to suburbia most everywhere else in the world (Europe, Japan, South America), and is an ideal density for a place that exists at the fringe of the Northeastern megalopolis.

6. Connectivity. (Not shown). A light rail line would connect to the nearest transportation hub, Vineland.
Triangle City lot density
These are traditional techniques laid over a substrate of Pennsylvania pragmatism. The primary failure of Victorian grid was the lack of provisioning adequate public green space; this issue is retained even in sprawl. It is an issue some people just don't get. By utilizing an overarching plan for prime structures and amenities, and enforcing provisioning of secondary ones in land-use covenants, this issue would hopefully be curtailed.

6 comments:

  1. What's the length scale for the map/sketch?

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  2. Here's the Google Map. The scale in the corner shows 2000 feet.

    The two main roads defining the city are about 2 miles long, and the city is triangular in shape, which means--A(t)=1/2bh (2x2)/2=2--that the city would be two miles square, or the same size as the Holme plan for Philadelphia.

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  3. Well, I threw the suggestion out there but had no idea you'd take me up on it! This is a fascinating exercise, and one that looks like it was a lot of fun to do. From the dimensions you given it appears this city should be entirely accessible either by foot or bicycle? At least, it looks like no one will be much more than a five minute walk away from one of the commercial corridors. Would any streets, or segments of them, be car-free? Also, the park on the northern edge seems to be serving as an urban growth boundary -- would there be an equivalent on the southern and western edges?

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  5. Charlie--It was fun. Notice that I used different line weights to show how wide the roads would be.

    (a) The streets would be naked (aka shared space), which means they would not be closed to traffic, but would still be pedestrian-oriented. This type of street design is now common throughout Europe.
    (b) The park on the northern edges is indeed an urban growth boundary. The lack thereof on the southern edges is due to the fact that, if the city needs to expand off its plat, farmland to the south and west can be incorporated in the same manner as what is already on the plat. I would hypothesize that this city could eventually become a diamond 4 sq miles in size, and double the design population of the current city, before a new growth boundary on those edges would be enforced.

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  6. To be honest, this doesn't look very good to me. I'm not talking about the urban design, which is okay, but about the location and the idea of a new greenfield city. Triangle City, NJ would not be near anything, so almost all residents would own cars, and drive them to Vineland for many errands. The main arterial roads at the edge of the city would have to be widened, literally paving the way to low-density sprawl along them.

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