Monday, November 28, 2011

Street Narrowing, circa 1200 A.D.

Back in April, I ventured a few ideas on the topic of street narrowing, a remedy I'd suggested for certain overscaled urban streets.  Although modern examples of narrowing (here meaning physically building into the right-of-way) are quite rare, the process was commonplace several hundred years ago, according to this account of medieval Bologna, which apparently was more accommodating of student housing needs than many 21st century American cities:

"....every street is lined with arcades, or portici.  The original ones date from the 12th century, when the comune, faced with a housing shortage compounded by the presence of 2,000 university students, allowed rooms to be built on to existing buildings over the streets. Over time, the Bolognesi became attached to them and the shelter they provided from the weather."
Arcades on a Bologna arterial street.
This solution was elegant, essentially representing a sale of air rights over the existing street.  Residential space was in the aggregate expanded considerably, while pedestrians gained a network of covered passageways providing a shield from bad weather.  Remarkably, in the centuries since, it appears that few if any stores have expanded to fill the covered space beneath the arcades.

This concept was not limited to Bologna, as many other European cities underwent a similar transformation around the same time.  Even the remains of Roman cities show the same process at work.

Could this process be applicable to cities of the present day, as one of several potential approaches to right-of-way narrowing?  Although many of New York's office buildings constructed since the adoption of the 1961 zoning resolution  did adopt arcade-like features in satisfaction of density bonus incentives, these were never constucted over sidewalks, and sometimes were separated from the walk entirely, rendering them useless as a source of shelter for those on foot.  One can imagine a very different streetscape in the process of emerging had the code rewrite, instead of encouraging setbacks and plazas, offered for sale sidewalk air rights on the same terms as Bologna of the 1100s.

Related posts:
Are Narrow Streets a Realistic Objective?
Thinking Small: The Narrow Streets Movement
Josh Mahar's great article on street narrowing at CityTank: Reversing Haussman

Tuesday, November 22, 2011

Jane Jacobs on Narrow Streets

It's the rare observation about urbanism which one won't find already made, or anticipated, somewhere in the writings of Jane Jacobs.  It's no surprise, therefore, to find that Jacobs was also one of the first writers to make a case for the functional benefits of narrow streets.*  Like many of her arguments, this one was based on first-person observation of real-life examples:
"Narrow streets, if they are not too narrow (like many of Boston's) and are not choked with cars, can also cheer a walker by giving him a continual choice of this side of the street or that, and twice as much to see. The differences are something anyone can try out for himself by walking a selection of downtown streets.
This does not mean all downtown streets should be narrow and short. Variety is wanted in this respect too. But it does mean that narrow streets or reasonably wide alleys have unique value that revitalizers of downtown ought to use to the hilt instead of wasting. It also means that if pedestrian and automobile traffic is separated out on different streets, planners would do better to choose the narrower streets for pedestrians, rather than the most wide and impressive. Where monotonously wide and long streets are turned over to exclusive pedestrian use, they are going to be a problem."  
-Downtown is for People (1958)
I'm not sure if we ever learned which Boston streets Jacobs considered too narrow (surely not Acorn Street!), or if that was an opinion she later changed, but the arguments stand nonetheless.  One concrete example is also provided:

Maiden Lane/vision63
"The real potential is in the street, and there are far more opportunities for exploiting it than are realized. Consider, for example, Maiden Lane, an odd two-block-long, narrow, back-door alley in San Francisco. Starting with nothing more remarkable than the dirty, neglected back sides of department stores and nondescript buildings, a group of merchants made this alley into one of the finest shopping streets in America. Maiden Lane has trees along its sidewalks, redwood benches to invite the sightseer or window shopper or buyer to linger, sidewalks of colored paving, sidewalk umbrellas when the sun gets hot. All the merchants do things differently: some put out tables with their wares, some hang out window boxes and grow vines. All the buildings, old and new, look individual; the most celebrated is an expanse of tan brick with a curved doorway, by architect Frank Lloyd Wright. The pedestrian's welfare is supreme; during the rush of the day, he has the street. Maiden Lane is an oasis with an irresistible sense of intimacy, cheerfulness, and spontaneity. It is one of San Francisco's most powerful downtown magnets.
Downtown can't be remade into a bunch of Maiden Lanes; and it would be insufferably quaint if it were. But the potential illustrated can be realized by any city and in its own particular way."  
-Downtown is for People
Now, Maiden Lane is an example of the "old urbanizing" of the 19th century speculative grid: the process in which large grid blocks along wide streets were subdivided by lanes of more human, and less wasteful, dimensions.  It was a process which occurred in nearly all cities of that era and plan, but nowhere more notably than in Melbourne.  Still, as you can see, Maiden Lane is not a "really narrow street," in Nathan Lewis' terminology, but of a width that is comparable to the major commercial thoroughfares of late medieval and Renaissance-era cities.  It is only narrow by comparison to the typical urban street laid out by the 19th century grid-makers (and in fact Jacobs' article mentions only American examples).

Jacobs later made additional observations implicitly supportive of narrow streets in car-free contexts:
"Paving which merged roadbed and sidewalk would probably induce more pedestrian use of roadbed space .... However, that is apparently only part of the answer.  In suburban shopping centers where "streets" are wide but thoroughly pedestrian and without curbs, people stay to the sides also except where something interesting to see has been deliberately placed out in the "street."  It takes tremendous numbers of pedestrians to populate the whole width of the roadbed, even in scatterings.  The only times pedestrians seem to use, or want to use, a street roadbed in this fashion are in cases of extraordinary floods of pedestrians, as in the Wall Street district or the Boston financial area when the offices let out .... In more ordinary circumstances, people are attracted to the sides, I think, because that is where it is most interesting." 
-The Death and Life of Great American Cities, p. 452-53
Jacobs was not the only urban thinker of this era appreciative of narrow streets (Bernard Rudofsky and Kevin Lynch had similar things to say, using more frequent reference to foreign examples), yet Jacobs stood out for looking past aesthetics to grasp the universal logic of urban form and human behavior that made places like Maiden Lane work so well. 

*Raymond Unwin in 1909's Town Planning In Practice made several references to the aesthetic merits of narrow streets in medieval towns, and even criticized the minimum street width ordinances of his day, but did not dwell on these streets' urban functionality (and, ultimately, did not take literal inspiration from them in his own designs, indicating that he did perhaps see them as functionally obsolete).

Monday, November 21, 2011

Vancouver Update: The Apartment House Cometh

"When [planner Harland] Bartholomew asked what abuses he should consider in the [Vancouver] interim zoning by-law of 1927 he was preparing, the chairman replied that 'the only serious abuse . . . is the intrusion of undesirable apartment houses into residential districts . . . .'"  -from Zoning and the single-family landscape: large new houses and neighbourhood change in Vancouver
A few weeks back I brought up Robert Fogelson's finding in Bourgeois Nightmares that restrictive covenants (and later zoning regulations) were fundamentally intended to prevent speculative increases in land value, rather than, as one might assume, to guard against value declines (it's an idea I've also discussed here).  A story out of Vancouver, about an upzoning of a formerly single-family residential area along an arterial street now served by rapid transit, shows how this same concern – and specifically an equation of value increases with perceived neighborhood decline – are still very much alive today:

"Six months after Vancouver City Council approved a plan to transform the Cambie Street corridor, homes in the area have nearly tripled in value and some residents fear development will ruin the neighbourhood. ... last month a block of 10 homes along Cambie Street near 41st Avenue sold for $3.4 million each — nearly three times their previously assessed value."

Although the article quotes one homeowner who is dismayed at this turn of events, it appears most are content to take the developers' money without complaint – and why not, since the city has in effect handed each of them a winning lottery ticket, the proceeds of which are derived from public investment in the new rapid transit line.  There seems to be a shared understanding among residents, however, that the changes afoot along this corridor will "ruin" the neighborhood, a refrain that has been heard a thousand times in American and Canadian cities since the late 19th century. 

A primary purpose of the Vancouver zoning code, as shown by the introductory quote, was after all to enshrine in law the anti-urban prejudices of progressive planners and well-to-do homeowners in the face of the increasing desirability of apartment living for Vancouver residents (the fear of an "intrusion" was no doubt motivated by visibly growing demand for apartments).  The zoning map, largely unchanged in its important features since the 1920s, still carries out this mission, barring apartment housing from around 70 percent of the city area.  In the face of this suppression of supply, any rezoning of a formerly single-family detached area for mid-rise multifamily housing is bound to result in especially steep increases in land value, with or without adjoining transit.

Rather than causing a re-examination of land use policy, the soaring home values evident in the city seem to have resulted in the blame falling on foreign buyers, and especially Chinese buyers.  The chain of causation may be backwards, however: rather than it being wealthy buyers who are bidding up property prices, is it possible that wealthy foreigners are simply among the few who are able to buy into Vancouver's already supply-constrained market?

The Zoning and the single-family landscape paper, although almost 20 years old, summarizes the situation best:
"The research concludes that Vancouver addressed symptoms of the problem but not its cause: a zoning practice that continues to exclude the less affluent from single-family zones. Vancouver needs to espouse a more inclusionary zoning schedule that adopts the compact land use and mixed tenures typical before zoning and preserves the traditions of local residents. Otherwise, the zoning changes may preserve single- family areas for affluent immigrants as the Vancouver market aligns itself with the global market."
h/t Market Urbanism for the article.

Related post: Vancouver and the Zoning Straitjacket

Thursday, November 17, 2011

Thursday Old Urbanism: Western Hemisphere Edition

On a gray November afternoon for those of us in the northeastern United States, a few colorful images from New World cities of non-Anglophone origin:

Buenos Aires
Rio De Janeiro (favela)
Quebec City

Tuesday, November 15, 2011

Ever Since Euclid

Euclid v. Ambler is one of the best known cases in American land use law.  Entire books have been written on that pivotal 1926 decision, and enough law review articles to fill several more volumes.  The attention is deserved: in the simplest possible terms, the case marks the dividing point between dueling conceptions of property rights, one being my right to do what I want with my property and the other being my right to tell you what to do with your property.

Although their arguments have been largely forgotten, several state and federal judges of the 1920s wielded natural rights principles to strike down early zoning ordinances. One of  these was none other than the district court judge in the Euclid case, David Courtney Westenhaver:

"The argument supporting this [zoning] ordinance proceeds, it seems to me, both on a mistaken view of what is property and of what is police power. Property, generally speaking, defendant's counsel concede, is protected against a taking without compensation, by the guaranties of the Ohio and United States Constitutions. But their view seems to be that so long as the owner remains clothed with the legal title thereto and is not ousted from the physical possession thereof, his property is not taken, no matter to what extent his right to use it is invaded or destroyed or its present or prospective value is depreciated. This is an erroneous view. The right to property, as used in the Constitution, has no such limited meaning. As has often been said is substance by the Supreme Court: 'There can be no conception of property aside from its control and use, and upon its use depends its value.'" -Ambler Realty Co. v. Village of Euclid, Ohio, 297 F. 307 D.C.Ohio (1924).
The logic is straightforward and simple.  If, as Westenhaver stated, property "includes the right to acquire, use, and dispose of it," then the removal of one of these valuable rights for instance, the right to use land for industry was a taking requiring compensation.  To hold otherwise would be analogous to concluding that a thief does not commit robbery so long as he leaves a few dollars in his victim's wallet.  And after all, states had long ago abolished the archaic fee tail, which removed an an owner's right to sell his property, for public policy reasons.  Was the right to freely use property any less important than the right to sell it? 

Unlike Justice Sutherland, the author of the Euclid opinion, Westenhaver was thoroughly unconvinced by the arguments of the Progressive planners that the zoning law was an enlightened regulation justifiable in terms of health, safety and the public welfare:

"The plain truth is that the true object of the ordinance in question is to place all the property in an undeveloped area of 16 square miles in a strait-jacket. The purpose to be accomplished is really to regulate the mode of living of persons who may hereafter inhabit it. In the last analysis, the result to be accomplished is to classify the population and segregate them according to their income or situation in life."
Chief Justice Phillips of the Texas Supreme Court reached the same conclusion in 1921, with regard to a zoning ordinance which prohibited commercial uses in a district except with the approval of a three quarters majority vote of area residents:
"This feature [majority approval] of the ordinance, in our opinion, reveals its true purpose. It reveals with reasonable clearness that its object is not to protect the public health, safety or welfare from any threatening injury from a store, but to satisfy a sentiment against the mere presence of a store in a residence part of the City. ... But it is not the law of this land that a man may be deprived of the lawful use of his property because his tastes are not in accord with those of his neighbors. The law is that he may use it as he chooses, regardless of their tastes, if in its use he does not harm them." -Spann v. City of Dallas, 111 Tex. 350, 235 S.W. 513 (1921).
Baseless prejudice against commercial activity, Phillips held, or against those of lesser means, was not a sufficient justification for a taking of property rights without compensation, any more than baseless racial prejudice was sufficient justification for the race-based zoning laws struck down in 1917 by the Supreme Court in Buchanan v. Warley.

This entire line of reasoning was invalidated by Euclid, which held that, in essence, the right to use one's property for lawful purposes was not a property interest within the meaning of the Fifth Amendment at all, and which permitted the regulatory regime we take for granted today.  The Supreme Court's takings jurisprudence since that time, constrained by this holding, has come to reflect an outlook on property rights that one legal scholar has called "schizophrenic" (p. 1650).  A few libertarian-minded scholars, notably Richard Epstein, have been attempting to revive a version of this older jurisprudence, but there's no substitute for examining the original arguments that were pitted against each other in the early 1920s, and for making one's own judgments.  

Friday, November 11, 2011

A Walk Through Occupied NY

Update 11/15: As you've read by now, the settlement shown here was removed last night by the NYPD at the order of the mayor, who was quoted only a week ago stating his lack of objection to the new, higher quality tents that had begun arriving (see end of post).  Since the protestors apparently are barred from setting up new tents, it looks as though this will be the first and last post on this intriguing subject.

With the Washington Post running an article on the "do-it-yourself urbanism" of Occupy D.C.'s encampment, and Steve Stofka observing the emergent patterns evident in Occupy Philadelphia, I decided yesterday to hop on the Lexington Avenue Line down to the Fulton Street stop, just a block or so away from Zuccotti Park, the site of Occupy Wall Street, to see this nearly two-month old settlement up close.  I wasn't alone: a number of foreign tourists, maps and cameras in hand, were also gathered around what has apparently become a major attraction of Lower Manhattan.

Although some earlier photos I'd seen gave the impression of a scattering of tents, tables and ad-hoc meeting places, the park has evolved quickly into a very dense settlement with almost every square foot put to use, a consequence, in part, of the limited space within the granite-walled boundaries of the park, an infill process mimicking the growth of cities within medieval fortifications:

The path at right is the "Main Street" of the settlement, now lined with a mix of the tables of various groups and organizations, from anarchists to pacifists, as well as a large cafeteria, a library, and even some retailers with large, walk-in tents:

The path is generally six feet wide, broadening to eight or so in places.  No one brings in so much as a bike. The "residential" streets, running off this central way, are even narrower, some a couple feet wide, others leaving just enough space to step between the tents:

The police, as far as I could tell, stayed out of the settlement entirely, keeping to the sidewalks around the periphery.  Nor has there been a sign, at least since last month, of any imminent plans for eviction from either the city or the owner of the park (which is by law required to be open to the public round the clock).  The official stance, it is rumored, is to wait for winter cold to disperse the protestors. 

This assumes that the settlement has no capacity to adapt or improve from the current mish-mash of tarps and L.L. Bean summer camping tents  but is this place more analogous to a Soweto or a Rocinha?  I didn't distinctly notice it during my walkthrough, but the photos show the evidence: look closely at the top left of the first photo and you'll notice a pair of large green tents, the first of many scheduled to arrive shortly, and which have been cleared with the city:

"[The OWS members'] newest plan to install 27 military-grade tents designed to stave off freezing temperatures and precipitation, which they began to bring to reality Tuesday, is kosher with the city, Bloomberg said during a Q&A session after an unrelated press conference in Hell's Kitchen Monday."
For a supposedly rudderless movement, "OWS" seems to have set things in rapid motion at Zuccotti Park, although there would be some irony in the settlement coming to outwardly resemble a military barracks.  I'll need to check back in a week or two to see how things have changed, but by the looks of things no one's going anywhere anytime soon.

One last thing: population density.  As best I can tell, for this settlement, it is approximately 150,000 per square mile.

Monday, November 7, 2011

Nathan Lewis on "Stuff that Works," and New Narrow Streets Advocates

Nathan's latest, Let's Take a Traditional City Break 5: Stuff that Works, is now available on his site; In it he features a new development in Burlington, Ontario, mentioned here by commenter Nicolas, which has adopted a genuinely traditionalist design format. Nathan also mentions a promising new site,, which as far as I know is the only narrow streets advocacy organization out there. Is the movement gaining steam? Nathan's writings are cited as an inspiration for its creators, but they've very kindly linked to this blog as well. Check them out – there's a lot of great material on there so far, and I'm sure more will continue to be added.

Umbrian street at right.

Wednesday, November 2, 2011

Park Economics

What's an urban park worth to a city?  The question is straightforward, but despite the attention lavished on parks in the urban design literature, the economics of parks their measurable costs and benefits have received less attention.  Although "the science of city park economics is still in its infancy," according to the Trust for Public Land, a number of studies over the past decade have helped establish a consensus on a few key points.

Attempts to determine the value added by parks date at least back to the 1860s, when Frederick Law Olmsted attempted to calculate the increase in Manhattan real estate values generated by the creation of Central Park.  That the park increased the value of the land adjacent to it was obvious, but Olmsted might have considered several other key questions, such as:
  • Even if a park increases values, do those increases outweigh the the value that would have been gained from leaving the land available for development?
  • Alternatively, could the same or approximately similar increases in value be achieved with a reduction in park acreage (and thus an increase in developable land)?
  • Are values better served by a small number of large parks or many small parks, bearing in mind that many small parks are more expensive to maintain than a few large ones?
  • Do certain types of park programming and design increase values more than others?
A growing literature has begun to provide answers to these questions.   The Trust for Public Land has put together an accounting of the potential benefits of parkland, which, however, does not consider the countervailing costs of maintenance and land lost to development.  Other writers have made more questionable arguments. Among these is the one that revenue-positive parks are an economically desirable option in comparison to money-losing single use residential development, a point which is not so much in favor of parks as it is an illustration of the financial unsustainability of contemporary development patterns.

One of the best resources on the topic is a 2001 MIT Department of Architecture thesis, which was guided by several urbanist eminences including AndrĂ©s Duany and Eran Ben-Joseph.  Although I'd encourage you to check out this paper on your own, some of the author's most important findings include:
  • Homes adjacent to parkland receive a 22% price premium, but the premium rapidly drops off for properties beyond 600 feet from the park.
  • Large parks do confer greater premiums than small parks, but the premium is small compared to the effect of being close to a small park.
  • Smaller lots place a higher value on park proximity than large lots.
In light of these findings, the author recommends a series of small parks, rather than a handful of large parks, as the property value benefits of the former will typically exceed the maintenance savings of the latter. 

The intended use of a park also has a large impact on the effect the park will have on surrounding properties, according to the Trust for Public Land.  Space devoted exclusively to athletics, for instance, may actually harm adjacent property values; open space designed as a wildlife corridor or for stormwater runoff can also be a disamenity where an unlit and forested area is perceived to pose safety issues.  Large parks may also suffer from safety issues resulting from lack of use.  Certain common purposes for open space, therefore, may not coincide with the objective of improving surrounding property values.

None of this, I think, would come as a surprise to Jane Jacobs, who through personal observation and study reached many of the same conclusions:
"Conventionally, neighbourhood parks or parklike open spaces are considered boons conferred on the deprived populations of cities.  Let us turn this thought around, and consider city parks deprived places that need the boon of life and appreciation conferred upon them.  This is more nearly in accord with reality, for people do confer use on parks and make them successes – or else withhold use and doom parks to rejection and failure."
Even more to the point:
"City districts with relatively large amounts of generalized park ... seldom develop intense community focus on a park and intense love for it. ... Parks intensely used in generalized public-yard fashion tend to have four elements in their design which I shall call intricacy, centering, sun and enclosure."
Jacobs, in Death and Life of Great American Cities, was reacting the common tendency of planners in her era to dedicate excessive amounts of land for open space, such that the space became an obvious disamenity, and a liability, rather than a benefit.  Planning decisions about parks are going to revolve around more than the mathematical calculations of a developer, but having the tools to think about parks in a more objective way can aid in the creation of parks that are both successful and financially beneficial.