Evening star. [volume] (Washington, D.C.) 1854-1972, 1894-10-25
WATER AND SEWERS
DR.. Billings Gives Some Results of
His Observations.
RECOMMENDATIONS FOR WASHINGTON
Need for Pu'hing the improvement
Of the Water Supply.
A TALK TO THE DOCTORS

An unusually large number Of physicians,
as we'll as many interested persons not en-
titled to add IN. D." to their signatures,
attended q meeting Of the Medical Society
of the District of Columbia, held last even
ing in the Georgetown Law School building,
on E street between 9Th and 9th streets
northwest. They were attracted by the an
nouncement that DR.. j. s. Billings OF the
Army Medical Museum would speak on Fill
tration Methods Of Water Supply and Sew
age Disposal in Some Large European
Cities"
Dr. Billings in his address gave the re-
suits of his observations while recently in
Europe of the water supply and sewerage
of cities. Referring to Hamburg and Altoona
he said:
Hamburg and Altoona form one contin-
uous building area, so that it is impossible
for a stranger to see any difference in the
character of the buildings or the surround
ings; nor, when near the boundary, can he
tell whether he is in Hamburg or in Altoona,
unless it be by observing the uniform OF the
policemen whom he may meet.Tne two citles
are however, quite distinct in their forms
of government, and, what is more important
to us, in their water supply. Hamburg is
an old free city of over G35,OO0 people, whlch
retains many special privileges since 1t has
become part of the German empire, while
Altoona Is PruSSian city of about l4o,OOO
inhabitants, in which the conditions Of life
are in some respects not SO satisfactory to
the people as are those in Hamburg. Ham
burg took it's water from the river Elbe
above the town, though not above tidal in
fiuence, and supplied it unfiltered, while
Altoona took it's water from the same river
below the town, where 1t was h1ghly pol
luted with sewage, but filtered 1t through
sand filters before distributing 1T to the
people. In the great cholera outbreak in
1892 the cases occurred almost exclusively
in Hamburg, and in a map OF the two
cities on which the cholera cases are 10
Gated 1 saw the boundary line between
Hamburg and Altoona almost as distinctly
marked by the red dots as If it had been
shaded in for that purpose. 1t Is true that
there were cases in Altoona, but inquiry
showed that in almost all these cases the
sick had either drunk Hamburg water or
water directly taken from the river One of
the most remarkable bits of evidence is fur
nished by small court, the houses about
which are occupied by several hundred peo-
pie. This court Is in Hamburg, on the
boundary line between it and Altoona; but
for some reason 1t was not supplied with
water from the Hamburg works, but from
those of Altoona. Now, on the map just re-
ferred to there are no red dots on this court,
although they surround it on three sides
the fourth, or Altoona side, being free. And
entrance to this court-"Hamburger Gebiet,
Altoona Wasser'-so that l was not sur
prised to find that the rents of rooms in this
court had been decidedly higher than those
of similar rooms In the immediate neighbor-
hood-since its inhabitants had the benefit
of both the privileges of the free city and
of the pure water Of the Prussian town.
Hamburg's Filtering basins.
1.-THE municipal authorities of Hamburg
had decided in 1890 to construct u system
of sand filters for their supply, and after
the cholera outbreak, work on the new sys-
tenn was pushed vigorously, and it was put
into operation in May, 1898. At the same
time the point of intake was moved higher
up the river, but even at this point the
river water is still impure, being contain
mated by the sewage of towns higher up,
and by the numerous barges and boats on
the river, SO that the water contains over
10000 bacteria per cubic centimeter, and
among 'hese, during this last summer, there
were at times forms of spirilla hardly to be
distinguished from the genuine cholera
spirillum
1.-THE essential features OF the new fltra-
ton works are:
Il. The of sedmentsry basins
'2. The dividing the filtering surface in
to numerous small areas, each Of which
can be at Cnce disconnected without inter
ference with the others, and
80. The management OF the work under
constant meteorological inspection.
There are four settling basins, each
holding water enough for about one days
supply, and each having an area of about
twenty acres. One of these is filled and
the water allowed to stand for TWEEN ty-four
hours, to allow of the getting of the larger
suspended particles of clay, etc. The clear
ed water is lien pumped on the filter beds,
the sediment removed If there is enough to
make it necessary, and the basin is ready
for a fresh supply. Last summer there
were twenty-five Alter basins in use, but
more are to be added, for which space has
been reserved. These basins are parallelo-
grams, each having a surface of about two
acres. The filtering substance is composed
Of layer of about three feet in depth of
a. o,.~ H.
sand, below which is an eight-inch layer of
gravel, and an eight-inch layer of small
stones. The water is admitted with special
care to disturb the surface little as pos
sible, and the supply is regulated so as to
secure a depth of water of about three feet
above the sand surface. This height is an
important matter, for upon 1t largely de-
ponds the rate at which the water passes
through the filter the great object being
that this rate shall be uniform all over the
bed, and that it shall nowhere exceed 100
millimeters per hour, and there are special
and ingenious arrangements to secure this,
which give about 525 gallons of water per
acre per day.
Each filter bed has a separate outlet,
" 18th the means of obtaining samples Of the
filtered water, and samples from each filter
are tested Internationally once day under
ordinary circumstances. AS rule, the
number OF bacteria found is between ten
and forty per cubic centimeter. If they
rise to 100 per cubic centimeter 1t Is con-
cluOed tnat either the depth OF the water
over the filter bed Is too great or that there
is something wrong with the filter. When
the filter becomes SO INSTRUCTED by slime
that the required amount of water does not
pass, it is empted, the surface layer re-
moved, and fresh sand put in it's place.
Subs0il Water.
TT will, of course, occur to YOU" said the
doctor, that II filtration of very impure
river water through less than five feet
thickness of sand is sufficient to render it
harmless, subsoil water taken from a depth
Of twenty-five or thirty feet ought also to
be harmless under all ordinary circum-
stances, and this, no doubt, Is the case.
The exceptions to this occur in the case Of
shallow wells, which become polluted either
through assures and crevices connecting
with leaky sewer or privy vault in the
vicinity, or by surface matters passing down
the side of a well of the old form-that is,
one, two or three feet in diameter. With
iron pipe wells the danger of this last form
of contamination Is small, and with care
may be reduced to nothing.
"The soluble portions of sewage may pass
with little change through fifty feet or more
of soil or sand, and, in this way, the chem
ical analysis Of well water may show
from the amount of chlorides, nitrates and
other nitrogen compounds that sewage is
being filtered into the stratum Of subsoil
water from which the well takes it's supply.
and vet the focal bacteria from such sew