Friday, August 27, 2010

Problems With New Traffic Signal

08/27/2010 -- There are two apparent, and I believe significant design problems with the new traffic light that has been installed at the corner of Swan Street and Route 165 in Lambertville, which design flaws have resulted in unnecessary safety hazards affecting both pedestrians and drivers of motor vehicles.

One of those two problems -- the failure to "square off" the corner of Route 165, has caused a serious blind spot affecting drivers and pedestrians emerging from South Franklin Street out onto Swan Street. That flaw was specifically drawn to the attention of the Mayor and other City officials on a number of occasions, both before and after the installation of the traffic light.

The design defect was also specifically pointed out to one of the City engineers, Christine Ballard, during a "walk around" tour of South Franklin Street she conducted with a few residents, back before the final approval of the traffic calming project for South Franklin. I do not know whether she passed on that information to the Mayor, or to the other City engineer, who may have drawn the design for the traffic light.

And, I also specifically drew this problem to the attention of Council President Steve Stegman at one of the several meetings with residents on the traffic calming proposal. He chaired that meeting when the Mayor was unavailable to make it.

So, what I do know is that the City went ahead with the installation of this traffic light, and they ignored this serious design problem despite the fact that it had been specifically brought to the attention of several city officials.

The following two photos illustrate this first problem. The first one shows the actual line of sight of a driver if he or she is properly stopped at the stop sign at the bottom of South Franklin, and presuming that the front of his or her vehicle is bordering on the edge of the crosswalk. Such a driver could not see an oncoming driver, even if the vehicle was beginning up the ramp onto Swan Street.

The second photo illustrates where a vehicle has to be out onto Swan Street in order for the operator to be able to get a line of sight of possible oncoming vehicles making the turn onto swan Street. Any such driver must at the same time be attentive to possible vehicles proceeding down Swan Street as well. Note the location of the "crosswalk line" which would now be at the back of the vehicle! A driver would have to be nearly completely out onto Swan Street before he or she has a suitable line of sight of potential oncoming traffic coming off of Route 165.

Anyone driving a vehicle and entering onto Swan Street from South Franklin, has to actually drive out into the street in order to be able to observe whether any vehicles are turning right at that intersection. A driver traveling northbound on Route 165, who has a green light can currently "sweep around" that corner onto Swan Street, and may risk a crash with any vehicle coming out of South Franklin, especially one that has inched well out into the roadway in order to see if anyone is coming off 165.

The design for the installation of the traffic light should have included squaring off the corner so that vehicles making that right turn would be required to slow down and proceed closer to the actual intersection before making that right-hand turn. That would have made such vehicles more visible to drivers of vehicles coming out of South Franklin Street.

That is a dangerous flaw in the design and it should have never been approved that way by the City.

The second obvious design flaw is that the pedestrian signal button was installed on a post located behind a large black relay box that was also placed there at the time of the installation of the light. The installation resulted in another blind spot.

As is obvious from the photo, any pedestrian who is operating the traffic signal button on the Cottage Hill side of the street, simply cannot be seen at all by northbound drivers traveling on Route 165, and conversely, a pedestrian operating the signal cannot see any oncoming traffic because of the location of the signal box.

In fact, as the following photo illustrates, a pedestrian must literally step out into the highway to be able to see, or be seen by any oncoming traffic. The operator of any vehicle with a green light who wishes to make the right hand turn onto Swan Street, can currently "sweep" around very close to that corner because of the dangerous design. It would be very difficult or even impossible to stop in time if a pedestrian suddenly stepped onto the roadway to see if a car or other vehicle was oncoming.

Likewise, a vehicle with a green light who is proceeding through the intersection may well be traveling in the right-hand lane, and close to the curb.

The speed limit on Route 165 at that precise location is 35 miles per hour, but it is common knowledge throughout the community that drivers frequently exceed that speed.

Even under the best of roadway conditions (dry pavement, full daylight) and with good brakes, and good reaction time on the part of the driver, an average car traveling at 35 mph needs approximately 100 feet to come to a stop.

This federal standards chart, which became effective just at the end of April, 2010, is the most recent federal standard for braking distance requirements for three axle trucks, which comprise the vast majority of the truck fleet on the highway today. Therefore, it is the federal standard for stopping distances in feet that relate to the typical three-axle trucks one would likely encounter on the roadway today. PFC stands for "peak friction coefficient" and the stopping distances indicated are from the actual application of the brakes until the vehicle comes to a complete stop. They do not include the reaction time of the driver.

Thus, in the best of dry road conditions, a truck traveling at the allowed speed limit of 35 mph, would need a minimum of just under 100 feet to come to a stop once the brakes are applied. One traveling at 40 mph, would need a minimum of 125 feet to come to a stop once the brakes are applied.

As can be seen from this photo, any pedestrian in that blind spot, who therefore could not be seen by any driver coming up Route 165, and who stepped out into the roadway in order to be able to see if there was any oncoming traffic, would simply not have a chance if a vehicle traveling in the right lane was close to the intersection, regardless of whether any such oncoming vehicle was a truck or a car!


Therefore, it is my opinion that this traffic signal, as currently configured, is literally a pedestrian fatality just waiting to happen. The City should take immediate action to correct this problem. In fact, they never should have approved it with these design flaws in the first place.

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