Brian K. Copeland, P.E.
|
October 25, 2002 |
I commend your efforts on the development of the new accessibility guidelines.
However, there are a few instances where implementation of these guidelines
would be cost prohibitive or may not be feasible from an engineering standpoint.
The needs of public agencies and designers need to be balanced with needs of
disabled persons. My comments are as follows:
1. Protruding Objects (1102.5). Traffic signal controller cabinets are
frequently mounted on signal poles, especially in downtown areas where space is
constrained. These cabinets would violate your proposed 4" guideline. I agree
that these cabinets and other attachment to poles should be kept outside of the
pedestrian circulation path, but there need to be provisions for allowing
cabinets to be mounted on poles if they are outside the main pedestrian path.
For example, the City of Portland has hundreds of these types of controllers
mounted on poles. As written, this guideline would severely cramp design efforts
and would be very costly to agencies.
2. Detectable Warnings (1104.3). Truncated domes are used in the Portland area
for pedestrian/at-grade LRT crossings. When a blind pedestrian experiences
truncated dome treatments in the Portland area, they know they are about to
cross a rail alignment. Other options should be evaluated for curb ramps outside
of at-grade rail crossings (I have seen horizontal raised strips in some areas
that seem to be effective). There needs to be distinction between crossing a
road and crossing an LRT/heavy rail trackway.
3. Pedestrian Signal Phase Timing (1105.3). Changing the pedestrian walk time
from 4.0 ft/sec to 3.0 ft/sec will have significant, far-reaching impacts on our
nation's transportation system. By reducing the walk speed, green time will be
taken away from vehicle movements and the capacity of many intersections will be
reduced. This would lead to the need for costly capacity improvements at
intersections which most agencies cannot afford. Where did the 3.0 ft/sec come
from? How much has this been studied? We need data/proof that lives will be
saved if we do this...
4. Roundabouts (1105.6). What type of signals are we talking about? Requiring
all pedestrian crossings at roundabouts to include standard pedestrian signals
would be a mistake and would defeat the purpose of the roundabout altogether.
There are other ways (pedestrian activated warning flashers or signage, for
example) to help create a safe pedestrian crossing. However, there needs to be
flexibility to address this on a case by case basis. A signal of some type may
be desired on a multilane roundabout, whereas a low-speed, single lane
roundabout may only call for signage.
I have worked as an transportation engineering/planning consultant in the
Portland, OR area for the past 10 years and have broad experience in
transportation design. Please consider the above input as you
finalize the guidelines. Thank you.
Brian K. Copeland, P.E.
DKS Associates
index
previous comment
next comment