2008-02-24

Posted Elsewhere 1


While there are a lot of reasons to oppose superblocks, livable streets advocates should be wary of unthinkingly reinforcing Manhattan's grid system. That system is in many ways a contributor to today's congestion problems. See here for a discussion:
http://www.thevillager.com/villager_222/talkingpoint.html

Coming from Chicago, I am acutely aware of the difference in grid systems makes to their respective cities. In Chicago street density rises with development density: blocks in the CBD are somewhat less than 400' x 400' as more space is devoted to streets, resulting in enhanced walkability; in residential areas of the city blocks are generally a bit under 660' X 330' as more space is devoted to non-transport uses. Just as importantly, almost all of Chicago is serviced by alleys, moving congestion causing deliveries off the thoroughfares. [To keep the city easily navigable, all streets and addresses are numbered on a uniform grid of 800 units/mile; technically a Chicago "block" is 100 units regardless of how many streets it contains.]

In New York, by contrast, the dense spacing of EW streets means that a great deal of space is devoted to inefficient use. Many EW steets in midtown are glorified alleys: narrow and dark, primarily used for deliveries and trash collection, and unpleasant for pedestrians. All the while, since they are streets not alleys, they draw traffic and require full signalization at intersections. The avenues, on the other hand, are widely spaced to the detriment of both walkability and the overall transport capacity of the grid.

[It's worth noting how much dirtier NY is because of the grid: much trash is put out in bags on the EW streets because there is limited curbside access for bins/dumpsters. Bags are often not sealed or get ripped open allowing trash to escape. No wonder alternate side parking has been instituted to keep the streets clean! In Chicago, alleys allow for the mandatory use of bins/dumpsters and the streets require cleaning much less often.]

Obviously, NYC is largely stuck with its grid. But where large-scale developments are being planned, there exists an opportunity to improve upon it: add additional NS thoroughfares for enhanced walkability; shrink some EW streets and dedicate them to deliveries, while expanding other EW streets to give more space to enhanced street life.

0 Comments:

Post a Comment

Links to this post:

Create a Link

<< Home