The San Francisco call. [volume] (San Francisco [Calif.]) 1895-1913, 1895-11-24
Filled Districts in San
Francisco Steadily
Subsiding.
POSER FOR ENGINEERS.
The Subsistence May Render a
New Sewer System I'm
perative.
CHANGED GRADES NECESSARY.
Official Figures as to the Stability of
the Land on Which the City
Stands.
CHANGED GRADES NECESSARY.

a large proportion of the made ground
upon which San Francisco is built is
gradually subsiding, sinking, as it were,
INTO the very face of the earth, and,
though the subsistence is gradual and
through comparatively large districts uni
form, 1t Is sufficiently appreciable to cause
some very grave problems to arise for the
consideration of the civil engineers and
surveyors. So great, indeed, are the diff :
culties TO be overcome that their solution
may render necessary the establishment
of an entirely new system of grades for the
City streets and the final abandonment of
the present plan for the disposal of sewage.
The portion OF the City which is most
rapidly sinking is contained (roughly
speaking) within the limits set by Fourth.
Howard and Eighth streets and the bav
shore. In the "good old days when the
water came up to Montgomery street, this
district was huge morass, crossed diago-
nallly by range OF low sand hills. A
decade or so ago the territory was filled in
and an official street grade established.
Houses were erected, but so great has
been the subsistence that structures which
a few years ago were on the proper level
are now from foot to two and half feet
below the official grade. This is particu-
larly noticeable along portions of Sixth
street, where buildings have been recently
erected and their sidewalks raised to the
official mark. In every case there is a
marked difference in height between the
new walks and those Immediately dioin-
ing, which not long ago were at the official
grade, and in several instances the dis
crepancy amounts to twenty-four inches,
and at the corner of Fifth and Berry
streets the uniform depth of the streets
below the proper level is one and half
feet.
Inquiry at the office of the City and
County Surveyor yesterday afternoon re-
suited in the confirmation of the foregoing
statements. Mr.. Triton himself was not
found, but one of his deputies gave the
desired information, and he CHANGED to be
the man who has had TO establish the
official grades for new buildings in that
district. He said:
There can be no possible doubt that the sur
face OF the ground in the district you mention
is sinking continually, and sinking very rapid
~ too. l do not mean by that that there is
any Immediate danger OF its disappearing be-
meath the waters OF the bay or shat such
But the subsistence amounts to four inches
every year-enough to seriously hamper US in
our work OF establishing the grades there, since
each time we-have to start back on the high
ground and bring forward our levels.
One result of the lack OF stability in the terri
tory under consideration has been the neces-
sity of continual filling in on the streets of
that district 10 keep them up to the proper
level. do not think you can find q single
property owner on Sixth street, for instance,
who is not aggrieved because he has had TO pay
bills for grading that street at not infrequent