February 10, 2011

Remedial Street Grids

Street grids can be, in theory, an effective way to alleviate congestion on major suburban arterials. Frequently, lack of alternate routes, shared parking lots, and destination sprawl will concentrate traffic by virtue of the multiple car trips necessary to complete a set of errands.

Streetsblog DC has a great post about a rejected alternative to highway expansion in Charleston regarding a congested stretch of 4 lane suburban arterial. Read on:

The proposed secondary street grid would have been perpendicular and parallel to the existing arterial road.

To ease congestion on Savannah Highway, officials in Charleston have proposed an eight-mile, $489 million expansion of Interstate 526 through the towns of West Ashley, Johns Island and James Island.
One plan SC DOT rejected was developed by the Coastal Conservation League. The League opposes the I-526 extension, saying the project will destroy wetlands and perpetuate sprawl while having no effect on congestion on Savannah Highway. Their alternative proposal, “A New Way to Work,” could serve as a model for how to improve safety and make communities more livable while avoiding the expense and sprawl caused highway expansion.
“A New Way to Work” asserts that the congestion problems on Savannah Highway can be solved through street-level interventions in key locations. The biggest shortcoming of Savannah Highway, say League staff, is poor design. Their report notes that the road has a driveway every 80 feet, on average, creating a chaotic scramble between drivers who use the road to travel far distances and those who dash in and out of retail establishments. The lack of connectivity in the street network also limits drivers’ options, forcing traffic onto the arterial road.
What is needed, the report states, is a hierarchy of streets for different types of trips.

In its proposed redesign of Savannah Highway, the League would:
  • Eliminate many curb cuts
  • Install medians to control turning
  • Repair connections between cul-de-sac-style, disconnected streets
These three principles are recommended by the Transportation Research Board to reduce congestion, preserve scenic landscapes and improve safety of motorists and pedestrians.
“It centers around the power of the network streets to relieve the knots in the system,” said the League’s Josh Martin. “We’re trying to create a really great, livable, walkable multi-modal street.”


Biking No Man's Land II: Overpasses and Frontage Roads

In the first post about biking in downtown Danville, I chronicled the way land-use patterns tilt different parts of the same commercial corridor precipitously toward complete streets, or precipitously toward automobile only zones.

Southern downtown is frustrating, but the No Man's Land deal-sealer is the difficulty of negotiating its southern boundary. Biking in and out from the north is not the greatest, but after getting to the Iron Horse Trail, it is rather pleasant. To the south, though, there are two choices for leaving Dodge, both dangerous.  

As an ardent suburban biker, I know the roads that are good, and the roads that are dangerous. #1 most death-defying, damn-I'm-in-a-tight-spot place: freeway overpasses with onramps. #2: high speed (40+) frontage roads with gravelly <4 ft shoulders. Let's mix some Homer with our Gunsmoke and call them Scylla and Charybdis. A closer look:

Scylla Sycamore: Anatomy of a Beast

The only way to get to the Iron Horse Trail from the south end of town is to use Sycamore Valley Rd as it passes over highway 680. The screen captures and photographs below illustrate the difficulty of this endeavor.

1) Southern edge of Danville Blvd/Danville shopping district/Dodge.

2) Street view:

No bike lane, and the sidewalk ends. A subtle signal about who is welcome. Beyond that ped dead-end, cars merge to the right at will and at speed onto a gently banked ramp to 680 south, regardless of what color the light is. No pedestrian crossing there.

3) Street view a little tighter in:

No pedestrian crossing, but hey: a bike lane! It's hard to see, but by the island (just left of the 680 sign), a bike lane emerges. It disappears across the intersection, and then reappears by the next island, then disappears, then reappears across the overpass, then disappears, etc. It's comical that someone thought that a now-you-see-it-now-you-don't four foot margin between freeway-aroused automobiles and a bicyclist would even be worth the paint.

O = bike lane, X = No bike lane

A patchwork bike path described as such is misleading insofar as it implies that the object described is, in fact, a patchwork bike path. It fails to summon the agoraphobic terror one gets when biking across the gray expanse of what is not technically an intersection, but rather a space for cars to ascend to, or decelerate from, highway velocities triple and quadruple a bicyclist's. One feels as though there may as well be a bike path across a runway at SFO.

Of particular danger and high dexterity-need is the switch from the 2nd "O" to the 3rd "O" (L to R). One must cross a lane of cars, cars having just experienced the g-forces better known as the cloverleaf exit, cars with drivers having just tasted the anticipation of flooring it on the straightaway to even out a leftward-tugging centrifugal force, cars that are supremely totally not expecting a bike to appear in front of them, nor prepared to brake for said bike.

One must reverse this maneuver as one moves from "O" the 3rd to "O" the 4th. Cars leave the overpass, and right-turning traffic moves into the dedicated, banked right hand lane. One must somehow move from the right of these cars (while on the overpass) to their left (@ "X" the 4th and "O" the 4th). While doing this, one must contend with new cars being added to the travel way from the off ramp near "X" the 4th.

The reward at the end is safe passage on the Iron Horse Trail/Ithaka. I only take this route, somewhat counterintuitively, at night, when traffic is lighter. Doing so requires waiting to verify an absence of headlights on the cloverleaf, and then pedaling like hell. Scylla. I avoid it.

Charybdis: The Choke Point

After the complications of Scylla, it's anticlimactically simple. Heading south, with Sycamore to the left, a biker follows a bike path for a hundred yards, and then a generously wide shoulder picks up the slack. So far so good, until the choke point.

The picture does not show that the 3 foot shoulder is rather gravelly, mostly inclined (heading south), or that the woosh of 45 mph cars is muy frightening. Whereas Scylla involves timing and a mad dash to the other side, Charybdis requires a sustained, disciplined sprint. Since I am not terribly fast (12-15 mph being my guesstimated cruising speed with a slight incline), this stretch takes about 4-5 minutes, but feels like 20. The uphill, devilishly, increases as you get to the end.

The risk comes from the speed differential between the hypothetical car and bicyclist. A professor of mine once showed the following chart (I do not know the source, but in addition to being a transportation planning lecturer, he is also a transportation planning consultant, so I trust it) to indicate the effect that vehicle speed has on crash mortality.

The numbers on the axes are difficult to read, but a vehicle-pedestrian crash at any speed over 30mph stands an excellent chance of causing a near fatal injury or death.

Check for Pt 3 of the Biking No Man's Land series, coming soon, in which I'll review a few potential fixes pipe dreams.

February 9, 2011

A Biking No Man's Land in Danville, Pt I

Problem: south of the where the Iron Horse Trail meets San Ramon Valley Boulevard/Hartz Avenue, downtown Danville is a biking no man's land.

Old-timey Downtown Danville, the proper downtown north of the IHT access point, is well integrated with the regional bike/ped path. The historic downtown's "antiquated" land-use pattern of small blocks, on-street parking (with additional lots behind the shops), and retail make it an ideal place for pedestrians, and its convenient IHT access points only intensifies incentives for leaving the car at home.

The IHT, somewhat ironically, marks the southern boundary of the bike/ped friendly zone. On the Google Earth screenshot below, the IHT is in blue, the historic downtown is the "A" pushpin, and the No Man's Land is outlined in yellow.

Downtown Danville. 680 runs North to South, from top of image to bottom, respectively.

The zone bordered in yellow could have been an asset, an extension of the historic downtown. Unfortunately, the difference between it and the downtown could not be more stark. Just north of the blue circle, blocks shrink, streets narrow, and stores front the sidewalk. South of the blue circle, the road widens to 4 lanes, (in some cases 5), and parking lots push storefronts back as much as several hundred meters from the (now perfunctory) sidewalk.

From El Nido restaurant to the street is +/- 300 meters

The Livery Mercantile is a lost place entirely: cabin-like shops in various shades of colorless brown held at a distance by a big parking lot forest. I avoid it. It's like, unpleasantly arboreal. Arboreal in the sense that there are no sightlines; it is hard to orient oneself; it is dark; the buildings actually do look like dark huts. Instead of following the predictable geometry of the courtyard/plaza blueprint (see above image; geometric assets aside, it's still just a car-choked variation on a classic pedestrian urban space [imagine filling this with parking, or the Plaza Mayor]), the Livery lot is an amoebic lagoon.


So let's be clear: this part of town is not friendly to pedestrians or bikers. If the historic downtown is where people go for a pleasant meal or a shopping stroll, or a midsummer festival, the No Man's Land is where you do the daily errands: Lucky, Walgreens, CVS, McCaulous, multiple banks, etc. The Bowling Alley. So it's a fairly vital part of any Danvillian's weekly life. Except for McCaulous.

If land use patterns made biking safe and desirable, more people would be free to make the choice to deposit checks, pick up groceries, etc, on their bikes. But in a place built for cars, there is only one option: cars. Unless you really enjoy going against the grain, like me.

As much as the land use planning decisions make this a tale of two Danvilles, one for cars and one for bikes/peds(/and cars, too; there really is plenty of parking, proof that you can have it both ways), what really makes the southern downtown a No Man's Land is access. Lack of it: getting to this area from the south, and getting back out of this area to the south present bicyclists with a dangerous set of options that only further discourage anything beside driving.

More on this in the next post.

February 7, 2011

Growth and the Role of Rail

When the cost of HSR is discussed in that way that makes it seems formidably, unAmericanly expensive, the context of HSR's pricetag is rarely established: i.e., that if rail does not happen, many billions will be spent, regardless, on freeways and airports. Obviously, rail does not end the need to spend billions of dollars on roads, freeways, and parking, but it relieves congestion and saves the expenses of expanding those networks. The San Antonio Express-News gets it right:

According to a study commissioned by the Texas Transportation Commission, during the next 20 years, more than $300 billion in 2009 dollars needs to be invested in Texas roads and freeways just to keep commute times from worsening. Adjust that figure for expected inflation and the cost balloons to $488 billion.
The gasoline tax, which provides most of the funding for road construction and maintenance, is expected to provide only $160 billion in revenue during the same period. Legislative leaders have characterized the state's transportation funding as a crisis: Texas is running out of money to build new roads.
California, long maligned as the golden state of governmental malaise, has embarked on a different path. In 2008, California voters approved $10 billion in bonds as a down payment on a $40 billion high-speed rail system that will link San Diego to Los Angeles and Los Angeles to San Francisco and Sacramento via the Central Valley.

Eventually public transit becomes cheaper (and more attractive) than continuing to expand road networks. Los Angeles hit a breaking point: look at the popularity/buzz around Villaraigosa's 30/10 plan to expand transit in Los Angeles. I hope more cities and states see those costs, too, and mobilize in favor of transit.

A good place to start would be spreading an appreciation for the fact that Caltrains saves 2.5 lanes of traffic on 101 during each commute. Is it more expensive to add miles of highway or close a $30 million operating budget for the beleaguered rail agency?

February 3, 2011

Automobile Dependence and the Limits of the Electric Car

Sometimes an argument is taut enough to (momentarily) suffocate any counters. A defense of gay marriage recently accomplished this feat. Below please find its transportation-savvy counterpart.

[He] may well be right that electric cars are the future of the automobile, the ultimate problem isn’t cars themselves—it’s the consequences of a car-centric culture.

Those consequences include, but aren’t limited to: Sprawling development patterns (which are massively energy-inefficient, destroy farmland and rural lifestyles, contribute to the concentration of the food system, and require massive amounts of infrastructure—electrical, sewer, and roadway—to exist), impervious surfaces that increase roadway runoff into streams and soil, car crashes (which kill 40,000 people a year and create a huge cost to public health institutions) the consequences of sedentary, car-based lifestyles (obesity, shorter life spans), and the weakening of ties to friends, family, and community, to name a few.

Publicola author Erica Burnett is responding to the argument that bike and pedestrian street improvements are wasteful and unnecessary because in the future, the climate problem will be solved by electric cars. The electric car meme is tempting, but it only scratches the surface of the lifestyle enabled by the automobile. And while e. cars are certainly a net improvement, climate-wise and oil-dependency-wise, reducing automobile dependence is just as important as reducing fossil fuel dependence.