Evening star., 1954-11-05
ConsuItants Foresee
Breaking Point Soon
For Bridge Traffic
BY George Beveridge

Federal planners were to try
this afternoon to agree on design
details for the newly authorized
Constitution avenue bridge, amid
predictions that existing Poto-
mac River bridges will be jammed
to "the breaking point" within
q year.
The dire prediction for the
future came in a preliminary re-
port to the National Capital
Planning Commission from the
New Haven highway -consultant
firm of Wilbur Smith & Associ-
ateS.
The consultants, making q
long-range study Of bridge prob
lens for the planners. estimated
the present daily average vol
ume of 224,000 cars crossing the
Potomac will leap to between
$4,000 and 375.000 by 1870.
Whether it's 800, 900 or 375. 900.
the report said. will depend on
whether Virginia and the Dis
trict build good enough ap-
proach streets and highways to
feed traffic on and off the bridges.
95 Per Cent Used Up
As of today, the report said,
cars during peak hours use up 95
per cent of the lane capacity of
all existing bridges-and that's
figuring an undesirably high
standard of capacity" 1t added:
This means that peak-hour
congestion can be expected
70 reach the breaking point in
approximately one year unless
relief is provided. Even this as
sumes that traffic distributes
itself at peak hours so as to
utilize the full capacity of all
bridges"
The report did not define the
breaking point" or say what
would happen when it is passed.
Neither did it say what relief"
could be provided within a year.
since a bridge couldn't be built
within ,that time even if it were
begun tomorrow-Which it won't
be.
AS the study progresses. the
Smith report said, the consult
ants will furnish later data about
% how existing and proposed
bridges will handle existing traf-
flee loads and CD where they
think future bridges should be
located to serve the predicted
1910 traffic.
IA Lanes Needed.
The consultants said they fig
ured every possible factor in
coming up with the future esti-
mates. AS minimum, they said.
IA new bridge lanes will be need
ed within the next Is years to
handle the 1870 volume.
Actually, they said, these IA
lanes appear to be in sight
through new bridges proposed.
including the new Constitution
avenue bridge (six lanes), a
Jones Point bridge (six lanes).
improvements to Key bridge
1.-TWO more lanes and rebuilding
of one Fourteenth street bridge
Cat least one additional lane).
But the consultants said they
are not sure yet that the pro-
posed bridges in sight-even with
II or more new lanes - will
fill the need if they aren't
located in the right places.
Improper locations" the re-
port said, "can mean more
lane capacity will be required.
The Smith studies have not ad-
vanced to stage of completion
to show the preferred locations
of the new bridges. This is being
further investigated"
Main Business.
The planning commissions
main order of business will come
late today, in considering a re-
port for handling traffic for the
new span Congress authorized
to cross the Potomac just 1900
feet upriver from Arlington Me-
mortal bridge.
The bridge would hit the Dis
trict side near Constitution ave-
. nue.. The big problem is' whether
1t should tie into Constitution,
already overloaded with Me-
mortal bridge traffic.
: A proposed solution to the
bridge problem, repeatedly
agreed upon, has been sub
mitted to a planning commits
sion committee by technicians
from the District Highway De-
partment. the National Capital
Parks and the planning commits
sion.
The report, worked over by
the committee, is to be formally
presented to members. TO satisfy
District officials, it presumably
will have to include plans to
make sure that both the Arling-
ton bridge and the new span are
used to their fullest capacity
- during busy rush hours.