The watchman and southron. [volume] (Sumter, S.C.) 1881-1930, 1909-02-10
GATUN DAM NOT UNSAFE.
This Is the Statement of the Scientific
American--NO Truth I'm Published
Criticism of Great Dam.

Panama canal, we are assured by rep-
utable engineering journals. The re-
ports that the dam is unsafe are stig-
matized as sensational and misleading.
and we are told that it is not only
safe, but actually much stronger than
necessary. The true story of the sit
uation is thus told editorially in The
Scientific American (New York; of
December rs:
THE Gatun dam, as completed, VIII
consist Of an artificial mound of sand
and clay, 1876 feet in height, about l.
500 feet in width, and extending for
5000 Ur 5000 feet across tn. valley
of the Chagres river, from hillside to
hillside. This huge mound is to be
| formed by means of suction dredges,
which will pump sand and clay. mix
ed with water, from the bed Of the
| Chagres river below the dam, on to
the site of the dam. Here, as the wa
ter drains away, the sand and clay will
settle into mass of very close consis-
| 'rncy, so close as to be impervious 10
seepagc. In orer to confine the de-
posted material within the proper
width of 1900 feet, and prevent it
from flowing away with the water,
two walls Of loose rock are being
| built entirely across the valley, one at
the foot of the slope on the upstream
side or lake side of the dam, and the
other on the downstream side. The
wall along the upstream toe, as COM
pleted will be 80 feet broad at the
top and 60 feet high. AS the rock-fill
was being built out across the valley
1t crossed the old French canal chan
mel, which runs through the site of
the dam. During the past 20 years
this channel had become filled with
silt and soft mud; and the engineers
decided that, instead of excavating
this material until firm bottom was
reached, it would be more economical
to dump the rock directly upon the
mud, and allow the fill as thus form
ed to settle through the mud until it
reached firm ground. AS the fill was
raised in height, it's weight at length
became such that the expected dis
placement occurred, the rock settling
down and forcing the mud UP into
mounds on either side of the fill. So
far from the settling causing any con-
Germ to the engineers, it is exactly
what they expected to take place; and
the greater the settlement, the more
they will be pleased. There is moth
Ing new in this, and certainly nothing
to warrant the attempt to stir up pub
lie apprehension, to say nothing of
congressional anxiety, regarding the
stability of the dam. Railroad en-
bankments are being made every day
by this very method of displacement
and when the rock-fill at the toe of
the Gatum dam has finally reached
the underlying solid material, which it
will do long before the dam is COM
pleted. the public need have no anxi-
ETY. as to further settlement"
The editor of Engineering News
(New York, December 24) makes use
of some pretty strong language on this
subject He says:
The structure at Gatun is as sound
and safe as any engineering work
could possibly be. Indeed, the critic
ism of the design made to us person
ally by one we'll known engineer ex-
pert in earth-dam construction is that
the dam is so absolutely safe that at
least half its width is wholly useless.
1t Is undoubtedly the case that the
long toe Of the dam on the seaward
side Is a concession to the fears and
the ignorance of some Of the engineers
originally connected with the work
who were better posted on bridge and
railroad work than on dam construc-
ton.
1T is not at all difficult, as we have
shown above, to account for the
alarmist reports concerning the Pana-
ma plans and work. Besides the inter-
views given out by the disgruntled
ones, whose ideas did not prevail, we
have the undoubted fact that the news
papers give large space to every scare
story from Panama and practically ig-
more statements Of responsible engi-
neers giving the real truth. The set
Ting of the waste rock dumped in the
mud in the old French canal channel
along the south toe of the dam has
been magnified into disaster of omi-
| nous portent to the whole work.
Stories concerning il have been pub
g IN fAta Il