The morning call., 1895-01-20

own doors a scene that is delightfully."-
charming and wonderfully beautiful and
impressive.
1t is a fieeting show, however, and is
possible only under such conditions as
have existed during the present winter.
The rainfall has been phenomenal in the
hills of San Mateo County, ranging from
forty five inches at Pilarcitos to thirty-two
inches at Crystal Lakes, while San Fran
cisco has had but little over twenty-five
inches. 1t was hardly anticipated by the
Spring Valley Water Company that the
big lake at Crystal Springs would ever
overflow. Once before, when the dam was
lower than it is now, a cascade was formed,
but the raising of the dam some twenty
feet at a subsequent period increased the
capacity of the lakes to so great an extent
that an overflow was not thought possible.
In constructing the dam a waterway was
of course provided, and it was needed, for
the rains of the past storm have been so
incessant as not only to fill the lakes to
their utmost capacity, but to cause an
enormous quantity of water to waste away.
The Spring Valley dam is regarded as
wonder by hydraulic engineers. 1t will be
the longest in the world when % feet have
been added, as contemplated to the pres
all other dams on the face of the earth. It
is $50 feet in length and crosses the narrow
valley OF San Mateo Greek. Built to with
stand the enormous pressure of a storage
of twenty thousand million gallons of
water, every known device in order to
make it absolutely secure was used in its
construction. The ground on the face of
the hills on either side was excavated to
the rock, and then the structure of great
pnncrptp blocks w laid n q iaDo ~ !, Of
feet. Upon this other great courses were
built, dovetailed one in another, until the
top was reached.
Behind this dam lay the Crystal Lakes,
originally but small depressions in the
hills, but now covering an immense stor-
age capacity, sufficient for all the water
that San Francisco can consume in three
years.
The San Mateo people have always re-
garded the presence of such an immense
body OF artiticially restrained water with
some misgivings and there are now many
timorous ones who are disturbed by the
fear that another disaster similar to that
of Johnstown impends. They think that
no structure can Withstand the enormous
pressure that the Spring Valley dam is sub
iected to, and argue that under the con-
slant and copious rains of the season the
grounds thereabout will become completely
saturated and unable to perform their part
in the support of the big dam. Therefore
they say it is best for the San Mateans to
be prepared for the unexpected and ready
to flee at short notice.
These fearful ones are largely in the
minority in the community, but their
forebodings have had some effect, for all
who laugh at the calamity, howlers, as
they are called, invariably conclude Their
remarks with anticipations of what might
happen if the dam went out.
Hermann SchuSsler, engineer of the
Spring Valley Water Works, who projected
and built this wonderful dam and who
ranks among the greatest hydraulic en-.
gineers of the world, laughs at the posi-
bility of calamity, and declares that nc
pressure that could be brought against the
structure could have the Slightest effect
upon it. at is founded on a rock and nc
seepage from underneath the foundations.
which alone could imperil the dam, could
take place The whole dam is one solid
mass of concrete and is good for centuries y
he says.
If the dam were to break, and that vast
body of water-nearly $50 feet high and
miles in length came sweeping down the
valleys the desolation would be indescib-
able. One of the fairest domains in all
California would be obliterated, and a
catastrophe which would arouse the pity
ing sympathy of the whole world would
inevitably result.
At a distance the body of water nom
looks like wide ribbon of white against
the dark ground of the dam, and at a
nearer approach the motion of the mighty
mass can be discerned. 1t is not until the
very foot of the fall is reached that the en-