Saturday, July 15, 2006

Jaywalking - A safety necessity

In order to cross Fremont Ave. near Fremont High school in Sunnyvale, there are two main ways to cross.

Crossing Fremont:

1) 'jaywalking'. Cross two lanes of traffic. Then wait on extra-wide landscape median. Then cross two more lanes of traffic. A pedestrian only has to cross two lanes of uncontrolled traffic at a time.

1.5) There is also a crosswalk available - the condition ends up somewhat similar to the jaywalking position, though without the comfortable median, and closer to the intersection, thus reducing the ability to see as much traffic.

2) 'Crossing at an intersection'. At the intersection of Sunnyvale-Saratoga and Fremont there is no median, so the entire street must be crossed at once. There is a right turn lane, three through lanes, 2 left turn lanes, a through lane, and an extra-large through lane. A total of 8 lanes. If a pedestrian must push the button and then wait until the start of the next light cycle. The green pedestrian 'walk' light will light up for a few seconds followed by the flashing don't walk. (If the pedestrian pushes the button after the light starts, they will have to wait for the next cycle.) The walk signal means that the through traffic and left turn traffic will not be in conflict. However, right turn traffic will still present a conflict. The Sunnyvale-Saratoga right turn traffic has a green light, while the Fremont right-turn traffic can make a right turn on red. This leaves 2 lanes in conflict.

Crossing at the 'official' location requires crossing 8 lanes at once, with two 'conflict' lanes. 'Jaywalking' requires crossing 2 lanes of traffic at a time, still with only 2 'conflict' lanes. Crossing at the 'official' locations gives the pedestrian a narrow interval of a few seconds every few minutes when they can cross. A 'jaywalking' pedestrian can cross at any time they feel safe. Crossing at midblock, pedestrians can see traffic for a distance and cross when safe. Crossing at the intersection, turning traffic can appear without being seen.

Intersections are engineered to maximize auto traffic. The number of traffic lanes may double at an intersection to maximize automobile throughput. However, this also makes it a greater burden for pedestrian crossing. The signals are also optimized for automobile traffic. Pedestrian walk signals only appear if a pedestrian presses a button before a signal cycle. Even if there will be a minute remaining on the cycle, a late press of the button will not bring a walk signal. (The signal needs to keep its options open for auto traffic.) A two minute through light, may only produce a pedestrian walk signal for a couple seconds, followed by 20 seconds of flashing don't walk, and then sold don't walk. If the cycle is going to be 2 minutes, why is the pedestrian light only for a few seconds? Why doesn't the walk signal last for 1 minute 40 seconds? And if the signal will easily last long enough for pedestrians to walk, why doesn't it just automatically put the walk signal on without pressing a button? The flashing "don't walk" is also the primary time to cross. Imagine if traffic lights for cars behaved similarly, with a 2 second green followed by a 20 second yellow.

And poor engineering at intersections is only another part of the reason why jaywalking is a pedestrian necessity. A location may have a curb cut for cars to enter a parking lot. Why not pedestrians? That implies a crossing location, and pedestrians have a desire to cross just as cars do. Furthermore, a pedestrian may move at 3 miles per hour, while a car at 30. A pedestrian taking a detour of 1/4 mile to get to the intersection to cross would be the equivalent of a car going 2.5 miles out of its way (just to pull a u-turn to go back the same distance)

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