Evening star., 1895-07-13
THE LONG BRIDGE
Condition of the Structure Described by
Major Davis
Little Work Done by the Pennsylva-
mia Railroad-The Obstruction
to Navigation.

In his annual report to the chief of engin-
eers, Major Davis, the engineer officer in
| charge of the Potomac river improvements,
devotes some space to statement of the
bad condition of the Long bridge.
"The bridge spans," he says, "rest upon
masonry piers built Of an inferior quality
of sandstone and founded upon pile and
grillage foundations, the grillage being at
the level of low tide. In order to prevent
these insecure foundations from being un-
| dermined by the river currents. large guam
titles Of rprap stone have been thrown
into the river and piled about them until
| there is now a series of immense mounds
extending across the river channel. So
great is this obstruction that the natural
discharge area of the river at the Long
bridge is reduced no less than thirty per
cent by these pier tons and the rip
rap stone deposited about them. The direc-
ton of the bridge is not normal to the di-
rection of the proposed. the present, nor
even the original channel, so that the piers
Cbeng built at right angles to the line Of
the BRIDGE are not parallel to the direction
of the current, but are obliIue to it, and SO
become themselves serious obstruction
during freshets A further obstruction
| arises during freshets from the height of
the existing bridge. The lower chord is
but 1913 feet in the clear above low tide,
while the floor is but 13 feet above low
| tide. The freshet of 1889 rose to height
| Of 1877 feet above low tide at the Long
bridge, and thus the superstructure of the
bridge diminished the maximum freshet
cross section by depth of no less than "a
| feet, or about one-fifth of the height which
| the water rose above low tide.
1.-THE cross section of the river at the
| Long bridge for freshet discharge has been
greatly diminished by reason of the closing
| of the Washington channel as a necessary
| part of the plan of improvement. This
diminishes the available freShet croSs-Sec-
of he hril about
| cent, based upon the freshet cross-section
| of 1877. The height as we'll as the dis
charge cross section of the freshet of 1882
! however, was much greater than that or
1877, and the area required for the dis
charge of such a freshet would be, much
greater than was estimated when the plans
| for the improvement were originally pre-
pared.
1.-THE draw of the existing bridge is badly
| located, having been placed near the east
erly edge of the navigation channel. AL
| though this channel has since been wild
| ened by dredging, the draw opening is
! oblique to the general direction of the
| channel and the current, and the opening
| is, therefore, a difficult one for vessels to
pass, and so interferes with the safe naVl-
cation of the river.
Necessity for Rebuilding.
"The project for the improvement Of the
Potomac river provided for rebuilding the
Long bridge over the Virginia channel,
with wide spans upon piers offering the
| least possible resistance to the flow of
| water AS the improvement progresses,
the necessity for this becomes more and
more urgent.
Long bridge, on account Of its faulty
construction, remains constant menace
to the interests on the river front above
it, and also to the work Of improvement
of the flats upon which the government
has already spent large sum. In the
event of a freshet occurring while the
river Is full of ice, the most serious results
are to be apprehended, and such a con-
tingency is not at all unlikely. Should an
ice gorge form at Long bridge it would
back up the waters of the river and over
flow portions of the city front. and through
the sewers above the bridge such of the
lower parts of the city as are drained by
them.
During the freshet Of June 1889, the
water reached (as above stated a height at
Long bridge of about thirteen feet above
low tide. The street surface at 18th and
3 streets northwest is about eight feet
above low tide, and during the freshet re-
ferred to the water was about five feet
deep in the street at that locality. Great
damage was done by the freshet of 1889,
but greater damage may occur from
freshet of lesser magnitude If accompanied
by an ice gorge. The bridge should be re-
built AS recommended by the board of en-
gineers. : Many complaints were re-
ceived during the spring from men en-
gagged in such business as brickmaklng
lumber, produce, ETC., and who do much
heavy teaming across the Long bridge of
the bad condition of the highway, and
aIter considerable correspondence with the
c1hcials of the Pennsylvania railroad they
at last agreed to raise the grade and put
1t In good condition, but up to date very
little work has been done to better the
condition"