Rock Island Argus. (Rock Island, Ill.) 1893-1920, 1906-04-13

City's supply Is 2,4OO Feet Long,
3O1 Feet High and Exceeds the
Great English, French and Belgium
Dams Combined.
After fourteen years of steady work
and at an expense of S7,70O,OOO the
new Croton dam near New York has
been completed. Water is filling the
enormous basin it makes of the once
beautiful valley and hillsides of the
CrotOn river and early in April is eX-
pected to reach the level of the top of
the spillway, says the New York Her
aid. When it does so there will be
1900 100000 gallons of water add
ed TO the supply for New York city.
When the diminished force of work
men which once numbered thousands
! ended their labOrs on the evening of
Saturday, March 10, the dam was fin
ished On the Sunday following James
| S. Coleman, chief of the firm of con-
| tractors which has built the dam, ac-
companied by engineers on the work
and the Rev. c. Cassenetti, rector OF
! the two Catholic chapels built for the
workmen, made a final trip over the
| construction railroad. From below the
dam they passed over the highway
which will span its crest up to the
Quarries, seven miles away, and then
returned to the dam. The rails were
then torn up and the dam was done.
Adding Il new wonder to the great
| engineering featS of the world, the
new CrotoD dam stands easily foremost
af of Lii, II
masonry. in height, length, thickness
and volume of water confined it has
no rivals. 1t is larger than the three
great dams of Europe combined. They
are the Vyrny dam in England, the
Furens in France and the Gileppe in
Belgium. In Egypt the Assouan dam.
built to control the irrigating floods of
the Nile, Is longer than the Croton
dam, but it is more Of a dixie than a
dam and is only 40 feet in height
| against 3o1 feet of the CrotOn's wall.
Soon the once narrow Croton river
will be a great lake ., 400 feet across at
the dam breast filling the valley be-
hind it for nearly twenty miles and
spreading at Hunters brook to an eX-
IRENE width of two miles. Three miles
from the new dam is the old Croton
dam, once regarded as wonderful
structure When the waters have ris-
en- to the top of the new dam the top
of the old Croton dam will be thirty
three feet below the surface. Below
the new dam the great stretch of land
In the valley belongs to New York
city. 1t has been graded and will be
made into public park. Already the
ha
ing torn down.
The new dam is in three sections, the
main dam extending 1,400 feet from
the south side of the Croton valley to
a point where the spillway and the
bridge span begin. The spillway
curves away to the eastward and is
LOCO feet long. Following the straight
line of the main dam is u steel arch
bridge 200 feet long. over this and the
top of the main dam is highway
twenty-one feet wide. Under the
bridge will flow the water after nass-
ing over the spillway.
When New York city acquired the
tract covered by the dam and lake 1t
was necessary to wipe out many roads
and bridges. To replace them the city
has constructed thirty-siX miles of
macadamized roads along the shores
of the lake.
When the present site was finally de
cided upon for the dam it was neces- |
sary to penetrate to the solid rock for
a foundation Behring'S through the sur
face earth found a disintegrated rock |
below, and it was not until a depth of |
eighty-five feet was reached that the |
solid rock was found. On this has been |
reared the dam. the most enormous |
mass of masonry in the world. 1t is |
2, 400 feet long from the south end of |
the main dam to the north end of the
spillway. At its base it is PIG feet |
thick, and this tapers toward the top, |
where it is ten feet across the top Of
the spillway and twenty-one feet wide
at the top of the main dam. The slope
of the inner wall is very slight
While the steps of stone below the
spillway top are rough and uneven,
the work there Is, if anything, more
carefully done than in the main dam.
The rough steps are made of great
blocks of stone from two to five tons
in weight, and they are Joined with
the finest precision. When the foods
OF early spring bring great volume of
water over the dam it will be full of
ice, giant blocks many tons in weight,
which must be crushed as they drop
from step to step below To meet their
shock and to reduce them to powder
the big stone blocks were put in the
face of the spillway.
When the water has risen to the top
Of the spillway and is flowing over it
its surface will be sixteen feet below
the leGel of the highway which crosses
the main dam and the bridge. The
water will be 1GO feet in depth at the
dam.
In the fourteen years since ground
was first broken for this dam the loss
Of human life there has been less than
that on any similar work in the history