Richard A. Perez, P.E.
October 28, 2002
Subject: Comments on Draft Guidelines for Accessible Public Rights-of-Way
Thank you for the opportunity to comments on these proposed standards. I write,
“standards” because even though these are labeled “guidelines”, guidelines do
not use “shall”. I have reviewed the “Building a True Community” report, which
was enlightening in many respects, and frightening in others.
These standards make no reference to distinguishing urban from rural conditions.
One could interpret that these standards apply everywhere, which seems contrary
to their intent by its intentional exclusion of requiring sidewalks everywhere.
Section 1101.3: The definition of curb line presumes curbside sidewalks, which
is not always the case. Perhaps reference it as the edge of pavements intended
for motorized travel, including parking lanes.
1102.2.2: Based on existing case law, I am extremely concerned that this could
eventually be interpreted as something different that what it says. An asphalt
overlay, which is essential street maintenance, not new construction or
alteration, has become a trigger for installing curb ramps. This is inherently
unreasonable, and therefore the definitions of alternations should be provided
for each subsection of Chapter 11.
1102.14: Define block face. Recognize that blocks can vary drastically in
length, depending on a variety of factors including local codes in effect at the
time of development, past development patterns, topography, and undevelopable
tracts of land such as freeways, railroads, bodies of water, and sensitive
areas. Recognize that zoning laws greatly impact the intensity of the need to
provide parking. On top of all this, Murphy’s Law will assure that whatever
location is provided will be as far as possible from any potential user. As
written, this rule is a great incentive for developers to provide only
off-street parking for all uses. If this is to be a requirement at all, it would
be far more reasonable to require a certain percentage of on-street spaces be
accessible (as with off-street parking) with a maximum spacing requirement
between accessible spaces.
1103.8.1: If the rail crossing is located where the track is in a horizontal
curve with superelevation, how can the pedestrian access route be level? Is the
railroad expected to remove the superelevation regardless of its safety impacts?
1104.2: What type of ramp is to be used for skewed intersections? These
standards only acknowledge the existence of right angle intersections. It would
seem important to provide directional guidance in the angle of departure from
the sidewalk, but the perpendicular curb ramp standard doesn’t allow for it and
the others do not provide any directional guidance.
122.214.171.124, and 1126.96.36.199: In areas of steep terrain, maintaining running and
cross slopes of 1:48 at landings may run afoul of 1103.5. Would this require
reconstruction of existing sidewalks until some indeterminate catch point is
reached regardless of length, or would a grade steeper for a sidewalk than a
street be allowed, and if the latter, how much steeper and how far is
1104.3.7: How is it expected that 4 feet of clear space between the curb and the
parallel vehicle travel lane be provided? Should the curb flare out for
additional street width to provide this? There could be adverse safety
consequences to increasing pedestrian crossing distances 8 feet at each
intersection. Turning vehicles will take advantage of this space, rendering moot
any sought-after protection, and increasing exposure to all pedestrians, as well
as increasing driver frustration as pedestrian clearance times are increased.
1105.2.2: To what extent should any organization, public or private, be expected
to reconstruct the vertical alignment of streets to achieve a cross-slope of
1:48 in a crosswalk? Consider this scenario: On an existing principal arterial
with a 12% grade with a posted speed limit of 45 mph, a developer proposes to
subdivide a parcel that can only be accessed from this arterial. (No, I am not
making this up – we really do have streets like this here). To meet this
standard, the developer would have to reconstruct the vertical alignment at 15%
grades for over 4200 feet using minimum ASSHTO standards, with cuts and fills
over 40 feet, which entail relocation of any utilities in the right-of-way. Now,
to make it more complicated, the parcel fronts the arterial on a horizontal
curve with 10% superelevation, so to meet this proposed standard, the horizontal
curve’s radius would have to be increased from 600 feet to 3000 feet, which
means 17 homes would be torn down, not to mention what other streets would have
to be reconstructed to meet this new alignment. Since the cost of these required
improvements vastly exceeds any value of the property, the developer sues the
road authority for an unlawful taking and wins. Public cost, millions; benefit,
But there is another potential outcome. Consider if the road authority allows
significant deviations from standards, reducing the design speed to about 25 mph
to make development of the parcel financially feasible, which still requires
over 1600 feet of reconstruction and a 2000 foot radius. How many people slow
down to 25 mph for a crest vertical curve on a road that is otherwise designed
for 45? I’ve done speed studies in similar situations and can assure you that
only ones going that slow are turning at the intersection. It will take only one
wrongful death claim to create a public cost of millions, but at least there is
some public benefit, right?
The problem here is not that the solutions are technically infeasible, but
rather that the they are financially absurd and/or sacrifice public safety,
phrases that don’t appear on the criteria for exceptions to these proposed
1105.3: This is an area where the unintended consequences could be worse than
the problem that this standard attempts to resolve. One of two things will
happen if pedestrian clearance times are increased. One option assumes that the
decrease in roadway capacity is not compensated for, in which case collision
rates will increase at significant public and private cost for the exclusive
benefit of very few. The other option is that this reduction in roadway capacity
is compensated for, in which case intersections will get bigger and/or cycle
lengths are increased. If cycle lengths are increased, pedestrian waiting times
are increased. At some point (which varies for each intersection and change in
turning movement volumes), the increase in pedestrian clearance times to
accommodate additional roadway width negates the increased capacity of the added
lanes, at which point grade separation becomes necessary. Retrofitting
interchanges in developed urban environments isn’t cheap, what with the cost of
right-of-way at high-volume intersections and access impacts. I priced one here
at $34 million.
What is really needed here is improvements in the reliability of passive
pedestrian detection that would allow variable pedestrian clearance intervals,
or a requirement for a longer pedestrian clearance interval based on 1106.3.4
(Few controller manufacturers provide this now, but if it were required with a
reasonable implementation period, they could modify the software to provide this
1105.5.3: The expense of providing pedestrian overpasses and underpasses is
significant enough that only in areas of extremely dense pedestrian flows can
they be justified. Requiring elevators will make it only less likely that these
will be constructed.
1105.6.2: This standard incorrectly implies that any location where a roundabout
might be justified would also justify a traffic signal. This is simply not true
– in fact, three will be installed in Federal Way over the next two years at
locations that probably never will meet signalization warrants. Perhaps more
importantly, this standard assumes that drivers will notice when a traffic
signal that stays green 99.99% of the time suddenly turns red. They won’t and
the results could be tragic. The warrants for signalization in the MUTCD have
evolved based on what has been clearly shown to not work. Putting signals where
the vast majority of drivers will never see them utilized has proven to be one
of those situations. A poorly placed signal will increase collision rates.
Furthermore, I fail to see why this is such a big issue in the US when it isn’t
in any other country using roundabouts.
1105.7: Requiring signalization of slip lanes suffers from the same problems as
requiring signalization of roundabouts. It would not be safer.
1106.2.1: The requirement that pedestrian signals be at least 10 feet apart from
each other may only be feasible by relocating crosswalks further from the center
of the intersection, which would then mean that the crosswalk may be more skewed
(see comments on 1104.2). This would also increase pedestrian crossing
distances, thus increasing the exposure of pedestrians to vehicular traffic.
The language regarding the orientation of the control face does not clarify in
my which devices currently meet this standard. A graphic would help. The vast
majority of pedestrian pushbuttons installed in the City are “H-style”, where
the pushbutton itself faces towards the subject crosswalk. I would prefer to not
further confuse the public with an orientation that is different.
1108.1: Given the minority reports, it appears that there is no consensus on an
acceptable design for detectable warnings. It is a colossal waste of public
resources to have constantly shifting designs. Taxpayers have a right to expect
a reasonable life cycle for publicly funded construction, and having 2-years old
curb ramps rendered obsolete, as has been done in the past, does not meet this
standard. No standard on detectable warnings should be required until consensus
1111.3: An alternative circulation path through construction zones cannot be
provided on the same side of a street with any reasonable degree of safety.
Adequate right-of-way would rarely exist. In the City of Federal Way, the widest
cross-section used in design of new streets has 17 feet behind the curb, 6 feet
of which is for street trees and 3 feet of which is reserved for street light
poles, fire hydrants, and other utility vaults. Even in the rare instance that
we have an 8-foot sidewalk, exposure to temporary blockages due to moving
construction equipment is a danger to any pedestrian, much less one that may
been unable to heed the warning of a flagger.
In my comments, I have attempted to be helpful, but in the time I’ve had to
devote to these issues, I have not devised many solutions. Many of these
challenges are endemic to the profession: finding the right balance of freedom
of movement and safety at cost that can pass the “red face” test in front of a
City Council. I wish you luck in finding that balance.
Richard A. Perez, P.E.
City Traffic Engineer