A tree doesn’t grow in San Francisco

August 13, 2008 11:03 AM

Why are the San Francisco sidewalks so wide, and why are so few trees and strips of grass planted between the sidewalk and buildings?

This question from a friend who lives in San Francisco, who noted that many of their residential sidewalks are quite wide, as in 15 feet wide, and run from the edge of the street to the buildings, unbroken by that little strip of grass and trees common in so many other cities.

Although I’m sure this isn’t the case everywhere in San Francisco, it is present enough to be noticed. Any idea why this might be the case?

posted by dreamphone to science & nature (25 comments total)

Probably because no one wants to pay to maintain that strip of grass. If you have no yard, you aren't going to have the tools to take care of a mini-yard, so might as well just avoid it all together.
posted by nomisxid at 11:12 AM on August 13, 2008

There also used to be driveways and garages on some of the bottom floors of may of the SF structures, if you can reference a local neighborhood I'm sure we could dig up some of the history for that area (destroyed by fire/earthquake, formerly business oriented/etc).
posted by iamabot at 11:14 AM on August 13, 2008

iamabot: My friend lives in the Marina, but his observation was related to many other neighborhoods in the city (some, of course, not all). Thanks.
posted by dreamphone at 11:23 AM on August 13, 2008

I think it's due to the fact that a lot of people park on the sidewalk (including work crews) and It's also expensive to put in trees.
posted by The Light Fantastic at 11:27 AM on August 13, 2008

It depends entirely upon the neighborhood, but anecdotally green spots in this city are invitations for:
- trash
- dog poop
- people poop

I also think installing such spots, when one currently doesn't exist, would launch a resident or neighborhood association into the byzantine labyrinth of approvals required from the city to accomplish such a task.
posted by quadog at 11:31 AM on August 13, 2008

Totally unscientific answer here, but as a native San Franciscan my take on it is that what you're describing is more common in the suburbs than in highly urban places - something that tends to go along with having front yards.

Not to mention that water has always been at a premium in California. All those trees and grass would use quite a lot.
posted by chez shoes at 11:47 AM on August 13, 2008

Friends of the Urban Forest have (has?) been ripping up sidewalk squares and planting trees. The tree is the responsibility of the person living in the house closest to it.
Sidewalks are wide because there are so many people that walk, normal sized sidewalks would be a pain. Not to mention all the events that happen at any time in the city where the streets are so crowded with people that a lawn would be decimated in a short time. Also, the soil is really sandy here, so it's hard to get grass to grow, another reason to have concrete instead of a lawn.
posted by idiotfactory at 12:17 PM on August 13, 2008

Soil being sandy doesn't mean things can't grow - it strikes me as sad that if you can't have a lawn, concrete is better. Better for what? Not for aesthetics or for the environment, that's for sure.
posted by agregoli at 12:26 PM on August 13, 2008

Eh, I don't know that lawns are doing much positive for the environment.
posted by electroboy at 12:42 PM on August 13, 2008

Exactly my point. Lawns are not great, but concrete isn't any better - in fact, it's marginally worse.
posted by agregoli at 12:54 PM on August 13, 2008

Lawns are actually better in terms of drainage. If everything is covered in concrete, all rainwater just drains into storm sewers. If there is a lawn instead, or some other sort of porous surface instead of concrete, the water is absorbed and eventually finds its way back into the water table. Not that San Francisco gets that much rain, but in principle this is a reason that grass/soil beats concrete.

Sorry for the derail.
posted by number9dream at 1:09 PM on August 13, 2008

Worse depends on a lot of factors. If no one is going to maintain the grass, then it's going to be worse aesthetically. Environmentally it's probably a wash. Grass doesn't soak up that much CO2 and requires some non-zero input of energy and chemicals to keep it looking really good.
posted by electroboy at 1:12 PM on August 13, 2008

Lawns are actually better in terms of drainage.

It's a negligible amount, since the street, sidewalk, roof and pretty much everything else is covered in impervious materials. The storm sewers are sized accordingly. Groundwater recharge isn't really an issue for anyone that's not drawing from the water table.
posted by electroboy at 1:28 PM on August 13, 2008

An attempt to refocus a little: a lot of sound ideas, but was seeking San Francisco-specific surmises (such as soil quality or ground-floor garage entrances, mentioned above). Certainly, trees are expensive, maintenance will be left up to the residents, etc., but isn't that the case in other cities, too? Water less of an issue elsewhere, certainly, I suppose....
posted by dreamphone at 1:29 PM on August 13, 2008

What you're referring to is the setback. Urban setbacks are typically small to nil -- this increases density and defines urban and commercial spaces. It fosters a kind of unity in the streetscape.

I agree that what you're claiming is a "common" wide setback with grassy areas between sidewalks and homes is in fact a suburban phenomenon, not an urban one.

The sidewalk width sounds simply like it's designed with pedestrians in mind.

In other words, your friend is living in a well-planned urban area which is pedestrian-friendly, and should be happy. If he or she prefers to live in the land of lawns and parking lots separating properties from the streetscape then perhaps cities aren't for him or her.
posted by loiseau at 1:38 PM on August 13, 2008

If I can add one more thing to conclude the stormwater derail, there's good stuff going on with this program to plan San Francisco as a series of watersheds.

More specifically about your question, there's the Better Streets Plan moving ahead that would plan streets in a way that includes green spaces for stormwater absorption. Their main challenge now is the sheer number of agencies involved, which is why it's hard to change the issue you're talking about. (I know some of the people involved in all this from grad school, full disclosure.)
posted by salvia at 1:50 PM on August 13, 2008

Much of San Francisco was built (or rebuilt) in a very short period of time, as far as cities go. Many of the neighborhoods were laid out and built all at once, sometimes by the same builder and/or developer. Obviously this is more the case in some of the outer neighborhoods, where you can see whole streets of the same exact three houses lined up over and over.

I would guess that the uniformity of sidewalk width and plantings (or lack thereof) in the city are because the neighborhoods were built quickly, cheaply, and uniformly, as opposed to evolving over time, as many other cities have.

(Speaking in generalities of course: in my neighborhood, the Haight, we have narrow sidewalks and plenty of trees. But we still have tracts of Victorians all built at the same time.)
posted by gyusan at 1:50 PM on August 13, 2008

This question from a friend who lives in San Francisco, who noted that many of their residential sidewalks are quite wide, as in 15 feet wide, and run from the edge of the street to the buildings, unbroken by that little strip of grass and trees common in so many other cities.

I can't think of any residential urban streets like this, except some city neighborhoods with detached houses w/their own lawns. Street trees, sure, but not a whole strip of pseuo-lawn.
posted by desuetude at 3:09 PM on August 13, 2008

Hm, just to clarify, I'm not talking about a wide setback or a lawn at all, just literally a 2' wide, occasional strip of grass or square of dirt with a tree in it. We have tons of this in Boston, in the most urban of areas. Guess my question really wasn't clear enough.
posted by dreamphone at 3:36 PM on August 13, 2008

No, I get what you mean. Sorry -- pseudo-lawn was a bit hyperbolic, I guess.

It's just not that common in most cities, I think. Usually there's just a square of pavement removed for a sidewalk tree, but there's not a whole strip of grass.
posted by desuetude at 7:12 PM on August 13, 2008

It struck me when I moved to San Francisco as well, and I did some research.

There is some information here and here. Because much of the city was reclaimed from sand dunes, it's not like East Coast cities where there are lots of old growth trees that got preserved as the city grew (ie. New England town squares with 300 year old trees and such). The city itself isn't that old, and much of the surviving older landscaping is in parks, such as Uncle John's Tree, which is thought to be one of our oldest at 110 years. Friends of the Urban Forest, mentioned above, has only been around since 1981, and though they've made a great deal of progress greening our streets, it takes years to see significant sustained growth that would resemble the urban landscapes of older cities with more established and organized tree programs and/or existing organic growth.
posted by judith at 9:18 PM on August 13, 2008

What I've heard from a few sources is that there originally were those planting strips but people paved them over. That's not much of a lead, but it's different than something that was originally planned that way.
posted by salvia at 9:50 PM on August 13, 2008

So a couple of varied reasons from my life in the city.

The classic San Francisco house architecture is an entrance on the second floor with a garage/utility room on the ground floor. Much of the city burned/fell down with the big quake (all the way up tot he golden hydrant up at the top corner of Mission/Dolores). When the city was rebuilt there was a shift in housing that I think contributed to the large spaces in front of the new structures but without much green spacing.

I think the root of it has to do with driveways/parking and overall sense of city planning. Much of the older block layouts downtown have very wide sidewalk space and it probably has something to do with the planning commission and building codes as areas transitioned to and from various purposes (industrial to housing, housing to industrial/offices)... (side note, did you know that nearly every building since the mid 60's in SF has to have public space....these tend to be balconies scattered around the upper floors of the buildings...and they are open to the public).
posted by iamabot at 2:19 AM on August 14, 2008 [1 favorite]

Relating to what iamabot wrote, a map of public spaces in San Francisco.
posted by Pronoiac at 2:51 PM on August 14, 2008 [1 favorite]

Here is an extremely interesting article from SPUR which also addresses the public/private spaces that iamabot mentioned. It compares San Francisco's architectural style unfavorably to the "classic rowhouse model" of such neighborhoods as Park Slope and Chelsea. In terms of why things came to be this way, the article largely places the blame on the automobile.

Much of San Francisco was built or rebuilt after the advent of the private car in the early 20th century. Even many older Victorian houses have been retrofitted with a garage, and a great many residential buildings feature a separate driveway for each unit. The result is not only the too-familiar “garagescape” — a dead, blank streetwall — but also, somewhat less obviously, sidewalks that are diced up by an inordinate number of curb cuts and driveways.
posted by whir at 11:55 AM on August 15, 2008