Evening star., 1933-03-19

only feasible alternative"
Covers Two Years.
Dr. McClintock's study of Chicago
traffic covers period of two years
Moreover, as director of the Erskine bu-
reau at Harvard, he has made extensive
surveys of many of Americas largest
and moSt densely crowded cities
In order that the limited way may
be best understood by tnc layman, let
it be described as a roadway for vehicu-
lar traffic upon which there is no cross
traffic and no direct accecs 10 abutting
property he states. The limited way
has a continuous elimination of cross
ings.
The most fundamental obstacle to
convenient and safe traffic flow is
croSs-trafhc at intersections At inter-
sections We find traffic lights. crossing
vehicles, crossing pedestrians. These
are definite handicaps and no amount
of widening of the highway will elm
mate them. Traffic signals cannot solve
the problem. Only the limited way
will do satisfactory job.
There are three types of limited
ways. the surface route, with special
treatment, the depressed way and the
elevated way. Each type has its par
ticular application. Any one of the
three will roe serve satisfactorily for
every need. But the practical adapta-
ton of the three will permit city traf-
fic to flow eS 5g.if.ly and smoothly as
traffic now flows in rural districts. Our
studies show us that the limited Way
has an 81 per cent greater capacity
than comparable surface routes reuuir-
ing traffic control.
What does this mean in money?
The answers are ready.
"A mile of surface route operating
at an average overall speed Of 20 miles
per hour, or at rate of three minutes
per mile, and carrying a daily traffic
of $4,000 vehicles. requires the expendi-
ture of 100000 vehicle minutes per "a
hour day. A mile Of limited way, op-
Grating at an average overall speed of
40 miles per hour, or at the rate of
l.5 minutes per mile, and carrying a
daily traffic of $4,000 vehicles, requires
the expenditure of $4,000 vehicle
minutes per 24-hour day.
75,cG0 Car Minutes Saved.
Thus we find that the limited way
saves $4,000 vehicle minutes per day,
or money saving to operators of
S937.50 per day computed at the rate
of l.25 cents per minute On the basis
of 365 days the annual saving is S342,-
1880, which may be capitalized at
per cent, giving a total Of $6,843. .750,
or the capital expenditure justified for
limited way construction over and
above that required for surface route
construction.
The same Is true Of accident cost
Without going into the entire statistical
structure, let me say that our report
shows that one mile of limited way
having total daily traffic of 50,O0O or
1860 900 vehicle miles per year, would
produce an accident saving over a COM
parable surface route of S20,553 per
year"
DR.. McClintock's report calls atten-
tion to several examples of limited way
construction. among them the West
Side Elevated Highway in New York.
Such highways will be part of our
metropolitan pictures in the near fu-
ture," he said, land the cities that pre-
pare now-and build now-are going
to reap the benefits that will result
therefrom. Limited ways are just as
vital to our great cities as are the
ings that now permit great masses of
people. to gather, live and work in
small areas
Reports Of the Erskine Bureau at
Harvard always are of interest. Wash
ington is now large city, especially in
regard to traffic What affects Chi
cago and New York also affects the
National Capital This column already
has called the attention to the future
need of SuperhighWays. Undoubtedly
they will come. It is the right time
now to think about them and study
them.
Greece Saves Fuel.
AS means of saving fuel, Greece is
limiting the operation of motor We
hicles with even and uneven number
plates to alternate days and permit
ting all vehicles to operate on Sum
days. according to the District OF Co.
lumbia Division of the American Auto
mobile Association.
The District Of Columbia division
bases its statement on a report from
the foreign travel division of the Amer
ican Automobile Association, which
handles the movement of cars for tour
ing abroad Cars with even-numbered
plates are allowed to operate on Mon
day, Wednesday and Friday, and those
with uneven-numbered plates on Tues
day. Thursday and Saturday
However. it was pointed out that the
new limitations in Greece affect only
cars registered in that country and
does not apply to those operated by
visitors
Such limitation may be evolved In
this country, but in all likelihood will
be because of congestion, not lack of
fuel. The situation In Greece, or here
should the occasion arise, might be
solved by each family owning two cars,
one with an even license plate and one
with an odd number