Evening star., 1924-12-07
ROTARY TRAFFIC AT STREET INTERSECTIONS HELD
ONLY FEASIBLE SOLUTION OF CONGESTION PROBLEM
Ease of Passing around
Circles Cited as Proof
! of Plan Merits.
Block System Criticized
as Dangerous and Time
Parking Hit.
RY RoBERr o. LITCHFIELD.

BY ROBERT o. LITCHFIELD.
In the District of Columbia there is
about 10000 600 square feet Of vehicle
roadway improved and unimproved.
Daily there are 900 vehicles using
this roadway.
a conservative estimate will show
that the average of these 900 vehicles
requires, for safe operating. at least 100
square feet of road area-a space by
% feet This means that third of our
roadway is in daily use. At the pres
ent rate of increase we shall be using a
full half of ii in five years. Please note
here that this estimate does not take
into account the fact that most of these
automobiles are concentrated in the
northwest section. but is figured as if
they were spread evenly over the city
as a whole.
Obviously in planning for the control
of this traffic, both for safety and ef-
ffcienCy. we must strive for the plan
that will insure not only the most
economical use of our street areas. but
will provide also for the greatest num-
her of users.
Cites Waste of Space.
The only measure we can apply to
gauge the use of street surface areas is
the pedestrian unit. A single pedestrian
can stand in square feet of street
space, Walking he requires space .
feet wide by feet long. This 10 square
feet Is the smallest area in which he
can maneuver with safety
For the same reason q passenger
automobile must be allowed 160 square
feet. the street car 500 and the bus $50.
SO we see that when the pedestrian
rides as passenger on a street car he
i1I. to fao IF
street area. on a bus from to 6 square
feet and, assuming liberal average in
a passenger automobile so square feet.
These figures are not offered to show
that We should disregard the apparently
wasteful passenger automobile in
scientific scheme of city transportation
but are cited merely TO emphasize the
need for such regulation as will prevent
wasteful use Of our already limited road
area.
Suburban Population Grows.
study of the census report for the
District Of Columbia will show that
in the suburban areas the rate Of
population increase in 1910 over 1900
was SIS per cent, while the growth
ot the city as a whole was only 1873
per cent greater In 1920, the subur-
ban rate of increase over 1910 was
S0.4 per cent, compared with 32.2 per
S'iii AtL tIlt city DIS d WHDlG.
1t is interesting to note that this
population increase has been to
large extent away from street car
service areas, and that the tre-
mendous home building operations of
the past four years have been al
most entirely Centered in these subur-
ban districts.
While thes" figures show the main
source OF the storage or dead-car
nrDbl lem. they also
reason for tolerance with the pas
$enEer automobile, which has been
thc transportation link between these
new residence areas and the business
district
Had our city streets been designed
primarily as automobile highways
We would not have the faulty street
design that glares at us today They,
cannot be rebuilt. they can hardly
be reshaped, they are bound too
stoutly to existing property values,
so We have to devise ways to get
around these faults either by gradual
elimination or by compromise.
Meanwhile there is the question of
relief from traffic conditions that
are prevalent now.
Time Limit Termed Compromise.
We can have a measure of relief
now merely by more efficient regula-
tion and administration.
We can adopt rigid rules for the
ranking and parking of dead vehi-
cles. Practically every large city is
now facing this action. Many have
compromised by placing time limits,
make-shift ruling generally made
to allow time for study. The con-
sensus of opinion seems to be, Why
have time limit as relief measure
when there is always a car ready to
occupy the space that must be va
Gated? This is sound reasoning. for
what with automobiles cruising
around in search of space where they
can be left the measure of relief
that comes from the limited ranking
or parking is much more than offset
by increased congestion in the streets
The trend now is toward rigid non
marking and ranking rules in the rush
hours. OF course, there is much to COM
mend in such a rule First the automo-
bile that comes from the suburban dis
triCt and is the only means of trans
portation for the man who uses 1t is
forced off the streets at an hour
when the street has the greatest ca
pacity to receive 1t, the non-rush
hour; and, second, when this car has
departed the street areas downtown
are correspondingly increased in
width by the elimination of waiting
cars. Hardship and unfair treatment
to that individual, however, is easily
apparent.
Circles Are Big Help.
The only relief that will be worth
while is the relief that is permanent
and that will be had only when we
have become more fully alive to the
changes that have taken place in our
city transportation system within the
past 10 years.
With few exceptions, there isn't
street in Washington, under the pres
ent system of traffic regulation, along
which it is safe to drive at a greater
rate of speed than eight miles an
hour for longer stretches than 200
feet, or whatever is the average
spacing between crosswalks, or
around circles, such as Scott and
Iowa, which, for all their converg-
ing ways, are more easily and more
safely negotiable than is the single
maneuver of crossing street inter-
section.
The rotary system of traffic con-
troll, of which the circle is good
example will give us as nearly an
ideal way as is possible when we
consider how little we can change
the present street design.
Rotary system Favored.
This rotary system will make 1T
possible for us to convert Sixteenth