30 April 2013

Caltrain Rail Yard Hide and Seek

The sexy part of redevelopment proposals are their hope, promise of sunnier prosperous days, and optimism for a better city. Relocating the orginal tenants or companies, even a railyard, is the challenge, and much less sexy to talk about. Continuing our analysis of the Caltrain Railyard Development Proposal, we look at where the 4th & King Railyard could or should go.
Technicentre Atlantique in Chatillon, France. Note Montparnasse Tower (top right) where Montparnasse Station is located.
Image: Wikipedia
When the Mayor's Office suggested "Let's be San Francisco and Take Down the Freeway", they provocatively, yet compellingly, proposed tearing down I-280 north of 16th Street and converting the 30 acre Fourth and King railyard into a high density mixed-use neighborhood. Also mentioned, but less emphasized were proposed new more efficient Downtown Extension (DTX) tunnel realignments. What was missing was a study of where to relocate the railyards.
Caltrain Centralized Equipment Maintenance and Operations Facility. Image: Caltrain
Avoiding the sticky issue of where to relocate the railyard is understandable. When proposing a new idea, especially one as striking and compelling as removing the freeway and yard to reconnect neighborhoods, deciding where the railyard will go distracts from the benefits of the proposal. That said, determining a railyard site is critical, and must be included in the analysis of whether or not to tear down the freeway or to build housing and other development on the 4th & King Railyard site.

If the railyards were relocated, there are a few locations that might work, but two issues are critical to a railyard:
  • 1: Proximity to the terminal station (Transbay Center)
    • 1 to 3 miles away is good
    • 3 to 6 miles is impractical but feasible
  • 2: Large site 
    • length ranging from 1/2 mile to 1 mile long
    • minimum 600 feet wide
The challenge is fitting such a railyard in an already urban area: San Francisco. One important note: I have no direct engineering experience regarding rail design regarding railyards, but I do understand the basic needs as mentioned above for a maintenance facility and a railyard where trains can layover when not in use.

I took a quick scan of several high speed rail equipment and maintenance facilities the UK, USA, and France. Due to the geometries of rail lines, a railyard is often NOT shaped like the rectangle shaped 4th & King Railyard. Most are actually shoehorned alongside existing rail right of ways, and have more of a diamond shape if trains enter and exit at both ends (see first image below), or more like a triangle if the yard dead ends and only has one entrance/exit (see second image below).

Technicentre (Yard and Maintenance) TGV Atlantique, Chatillon, France (left), 
Technicentre (Yard and Maintenance) TGV Le Landy, St. Denis, France (right)  Images: Google Maps using Maps Engine

So where to place the Caltrain yard, High Speed Rail yard, or both. Should it be a triangle shape, or diamond shape or both?

26 April 2013

To Be Tall or To Be Prominent...

What makes a hill more famous, more important, or more beautiful? Is it its shape? its height? its history? Maybe we don't notice hills for these reasons. Maybe we really notice them for their prominence. Continuing our look at hills - this time beyond Forgotten Hills, we look at what makes a hill in San Francisco (or anywhere) seem more important, significant or striking.
View of San Francisco's central "massif" from Mount Davidson to the south (left) to Mt. Sutro to the north (right). Image: Burrito Justice
Prominence is what it sounds like, how much does a hill or mountain predominate the skyline or region. A tall hill next to a slightly taller hill is not that noticeable. However a somewhat low hill that has no hills around it (think Telegraph Hill) is very prominent. An explanation follows, but review the graphics below for a quicker understanding, then read the descriptions.

Mount Diablo is a taller version of this. At 3,864 feet it's not especially high for a mountain. But with so few mountains near it, the mountain's prominence is 3,109 feet. By contrast tall peaks in a range like the Santa Cruz Mountains, just south of San Jose, will have a low prominence. For example, Loma Prieta Peak, the highest peak in the range is 3,786 feet high. Meanwhile, 4 miles to the west is Mount Unhunum at 3,486 feet: a comparably tall peak. However since Mt. Hunhunum  is in the range with Loma Prieta Peak, it's prominence is low, and only comes in at 586 feet.  By contrast, because Loma Prieta peak is the highest peak in the range, its prominence is high at 3,426.
Image: john curley
Prominence is defined as:
In topography prominence characterizes the height of a mountain's or hill's summit by the vertical distance between it and the lowest contour line encircling it and no higher summit. It is a measure of the independence of a summit. A peak's key col is a unique point on this contour line and the parent peak is some higher mountain, selected according to various objective criteria. (source: Wikipedia).

Vertical arrows show the topographic prominence of three peaks on an island. The dotted horizontal lines show the lowest contours which do not encircle higher peaks. Source: Wikipedia.org
For example, if looking at Hawaii's Mauna Kea and Mauna Loa we find:
Source: Peaklist.org
So which hills are the most prominent in San Francisco? First we think of what is tallest. Below is a list of the highest 40 hills in San Francisco. Following is a list of the most prominent hills. The well know peaks such as Mount Davidson, Twin Peaks, Clarendon Heights, Golden Gate Heights, Larsen Peak and Forest Hill round out much of the top ten peaks.

San Francisco's Highest Peaks

02 April 2013

Helipad on Valencia? At least it's not a restaurant.

Over the past 2 years it feels as if virtually every new retail space on Valencia is a new restaurant, whether converted from a closed space (auto repair shop becomes Dandelion Chocolate and Abbot's Sellar), in a new building (Farina Pizza, Mission Cheese), or from a long abandoned space (Amber Dhara).

Luckily we have a few new retail spaces that actually sell hard products, i.e. they're not restaurants. A stretch at Valencia and 19th has Aggregate Supply, a Chase ATM, and Gingko Home Furnishings, and we are thankful, regardless of their price points.

Now, the old 780 Cafe space (formerly The Summit) will become the new Betabrand Flagship Store. As reported in the Uptown Almanac, Betabrand is opening a large store in the space. Regardless of whether I can afford the lovely clothing they will sell, I appreciate their playful posters promoting the new store, with stories of a shaved Bigfoot, an arm eating sea lions and planned helipads (take that SF General).

The Sasquatch story is the funniest with descriptions of a new "100% pure Bigfoot fur" sweater.

-->
Introducing our new, limited-edition Sasquatch Sweater. Each beautiful garment is knit from 100% pure Bigfoot fur, shorn from our free-range herd in the Cascade Mountains.

It goes on to note that only "residual amounts of Sasquatch musk" are in the garments. In addition, the care instructions call for dry-clean only, but you can give it an authentic "wild" look by rubbing berries, dirt and bear scat into your sweater.

The storefront drawing caught my attention first with its helipad.