Evening star. [volume] (Washington, D.C.) 1854-1972, 1895-05-14
THE RIVER IMPROVEMENTS
Major Davis Reports on the Flats and the
Aqueduct Bridge.
The Work of ReclamatiOn-The Re-
pairs Made to the Damaged
Bridge Pier.

MAJ. DAVIS has made report TO the
chief of engineers of operations for the i'm
provement of the Potomac river during the
month of April. Dredging in the Wash
irgton channel, under the contract of the
New York Dredging Company, was con-
tinued through the month and good pro-
sress made. The operations were confined
to the lower part of the channel and con-
sisted chiefly in widening the same en- the
easterly side. A section of channel 500
feet long was dredged, the width obtained
being 400 feet and the depth 20 feet at low
tide. The total length of channel dredged
in the Washington channel under this con-
tract is 5000 feet During last month
1882 cubic yards were dredged, making
the total amount of dredging in the Wash
ington channel under this contract 1920
cubic yards.
The construction of the sea wall in the
tidal reservoir was commenced April 16
with small force of men. Operations
there have been greatly delayed by high
udes and rainy and unfavorable weather.
At the close of the month 80 feet of wall
had been completed and $50 feet We're in
progress Work on the training dixie on
the west side of the Virginia channel above
the Long bridge was continued and 1889
cubic yards of riprap were put in place.
The dixie has been extended $50 feet under
the contract with E. G. Gummel
All the dredged material is deposited on
the flats, and prac tically the entire area
to be reclaimed has been raised above the
overflow at ordinary high tide. OF the
12,ooO,OOO cubic yards estimated as neces-
sary to fill the flats, there has been so
deposited about 1O,G16,534.
The Aaueduct Bridge.
Maj. Davis says that the contractors for
the repairs to the Aqueduct bridge, the
Smaller & Schniglau Company, have con-
tinued operations on the cofferdam for
the repair of pier No 4, but no substantial
results have been attained, the work being
no nearer completion than it was at the
end Of March. The contractors at first
proposed and tried to do all the pumping
with an eight-inch centrifugal pump, but
iris was soon found to be entirely INSULT
cIent, and on April 16 a new ten-inch
Worthington duplex pump was put in place
being set down inside the dam about four
feet below low tide. This pump having
eeen put IN operation. depth of twelve
teet was reached April IL, when a large
leak occurred, filling up the dam for the
third time. The leak continued all the
next day, and April 10 pumping was re-
stunned and depth of eleven feet was
reached, when the dam sprung a leak at
the west end and filled again for the fourth
time
The next day was spent in repairing leaks
by diver. Pumping was resumed April p
and continued until the oath, a depth of
l91& feet below low tide being reached At
this level the bottom showed on the inside
OF the dam, at the northeast corner, agree
ing with the soundings previously made.
A Serious Leak
The same day a serious leak occurred at
the southwest corner of the dam, which
was checked somewhat but not stopped.
The pumping was continued and the same
level preserved through two high tides,
each of which increased the lead three feet
the leak meanwhile gradually increasingly,
until the afternoon of the 24th, when the
sheet piling broke, and the water burst
through the dam with great violence, the
sudden thrush of water being so great as
to completely fill the dam in ten minutes
So great was the force of the water that
the silt, ten feet in depth, was washed
away from the sheet piling on the inside
and churned into black foam as it rose to
the surface.
The break occurred at the bent at the ex-
IRENE southwest corner of the dam. This
bent is nine feet long, and a number of
sheet piles along its face were broken and
forced in by the water. due to the head of
1917 feet The sheet piling here. Major
Davis says, had been careleSsly driven, the
joists being open and the piles somewhat
split. The contractors did not sink the crib
through the bed of silt to the solid rock
but allowed it to rest in the upper part of
the silt stratum, about six or eight feet
above the rock. Outside of the crib the
triple sheet piling was driven to the rock
but under the conditions noted yielded un-
der the pressure, and the dam failed.
More PilfnE.
Tln