Lawrence T. Hagen, P.E., PTOE
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October 22, 2002 |
As a general comment, too much of the guidelines are attempts to eliminate any
engineering judgment in determining what is the appropriate traffic control
treatment. This leads to "cookbook engineering" where everyone just blindly
implements the cookbook approach. This one-size-fits-all approach is not good
engineering, is not good public works, and is usually not serving the overall
best interest of the public. Many of the recommended guidelines also seem to
have been done with no consideration of the fiscal impact. However, with the
ever-increasing demands and less money, operating agencies will have difficulty
implementing the proposed guidelines
Alternate Circulation Path - (1102.3, 1111)
I would suggest that an exception for short-duration blockages of pedestrian
paths should be included. If construction activities will block the path for a
few hours or maybe one day, you could spend more time and disrupt more people by
the installation and removal of the accessible and protected alternate path than
by the actual construction activity. Short-term closure of a pedestrian path,
where the pedestrian could utilize the other side of the road is a reasonable
alternative.
Minimum Clear Width (1103.3)
48" width exclusive of curbs will be difficult to obtain in many areas with
already-constrained right-of-way. I agree with some of the other posted comments
that perhaps we should look to including the curbs.
Pedestrian Crossings (1105.2.1)
I do not support the widening of crosswalks in a sweeping blanket mandate. In
many cases at large intersections, traffic engineers struggle to get the signal
indications located within the 40 - 150' distance from the stop line as mandated
by the MUTCD. Adding a couple of feet doesn't sound like much, but in many
instances that could be the difference between four and eight signal structures
(mast arms). I would prefer to see the 72 inch minimum remain, with guidance to
use the 96 inch width where there were higher numbers of pedestrians.
Pedestrian Signal Phase Timing (1105.3)
I am adamantly opposed to mandating a walk speed of 3.0 feet per second and
including the length of the curb ramps in the crossing time calculations. I
think that the local traffic engineer should have some discretionary authority
in these decisions. As a former municipal signal system engineer responsible for
the operation of over 1300 signals, I know that this would greatly decrease the
capacity of many intersections and increase driver frustration and road rage.
The signal maintaining agencies would receive numerous complaints from people
who have to sit and wait while the flashing don't walk interval continues to
time out, long after all of the pedestrians
have crossed.
Pedestrian Crossing Length (1105.4.1)
This requirement would seem to mandate the removal of unsignalized crossings
where the median width is less than 72 inches.
Pedestrian Overpasses and Underpasses (1105.5)
I believe that requiring elevators where there is a elevation change over 60
inches will make pedestrian overpasses too expensive to build and maintain. This
will significantly reduce the number of pedestrian overpasses built.
Roundabouts (1105.6)
I think mandating signalized pedestrian crossings at all roundabouts is one of
the silliest ideas imaginable. Many roundabouts do not warrant signalization, so
they would certainly not meet the warrants for the pedestrian crossings on the
approaches. There certainly are some roundabouts with poor pedestrian
performance, but many of those have design flaws in the roundabout. Many I have
seen have the pedestrian crossing at the circulating roadway edge. By properly
designing and constructing the pedestrian crossings at roundabouts, I believe
that peds can be properly and safely accommodated without signals at most
roundabouts. I think "YIELD TO PEDS" signs at the crosswalks should be tried
first, and signalized ped crossings should only be a last resort if nothing else
seems to work. However, either of these treatments should only be installed
after an engineering study determines that they are the most appropriate traffic
control device. I am also unsure what type of barrier is needed around
roundabouts. Would a small strip of grass or other landscaping (like that shown
in the picture) be an appropriate barrier? Guidance on the barrier is needed.
Turn Lanes at Intersections (1105.7)
Among other things, installation of the pedestrian activated signal at each
segment of the crosswalk crossing slip lanes creates a maintenance problem.
Large trucks routinely hit poles or devices that are out in the refuge island,
so the maintaining agency has to repeatedly replace the equipment. Also, with
the requirements of 1106.2.1, there is not room on most slip lane channelization
islands to accommodate the spacing requirements. Similar to roundabouts above, I
believe that if there is a problem, an engineer should study to determine the
most appropriate traffic control and be able to choose the best answer for that
intersection from the available solutions.
Accessible Pedestrian Signal Systems (1102.8, 1106)
My only comment here is related to the fiscal issue. In large metropolitan areas
where there are large numbers of signals, the costs of retrofitting all of the
signals with upgraded pedestrian features can be staggering, especially in this
day and age when everyone's budget is being cut. Additionally, by replacing a
simple pushbutton switch with a more sophisticated device that also vibrates and
emits sounds, you will incur more maintenance expense. Please understand, I
wholly support having accessible pedestrian devices where they are needed.
However, given the additional capital and maintenance costs, is it good public
works to install these devices where they may not be needed? Again, my objection
is basically the one-size-fits-all approach.
Thank you for the opportunity to comment. Please let me know if you need
additional information.
Larry Hagen
Lawrence T. Hagen, P.E., PTOE
Program Director - ITS, Traffic Operations, & Safety
Center for Urban Transportation Research (CUTR)
University of South Florida, College of Engineering
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