The record-union. [volume] (Sacramento, Calif.) 1891-1903, 1899-01-08
SAND FILTRATION AND OUR
RIVER.

The report of the joint committee Of
the Board of Health and the Trustees,
filed last August, on the publication Of
our water supply or the obtaining Of q
new source of supply for clear, pure
water, has been dragged out to ernpha-
size a suggestion that the Chamber of
Commerce should now investigate the
sand filtration system for treatment Of
river water before it is delivered
through the city mains, in the mean
while all other activity regarding q
better water supply to cease.
What that report contained and rec
commended has been misinterpreted.
After many citations Of the expert
'ences of other cities, one thing was re-
solved upon and that only, namely
that polluted water is the fruitful
source of disease, and the cause Of
many untimely deaths. Two sugges-
tions were made and only two, namely
that Sacramento can secure the necas-
.sary pure supply first from protected
deep driven wells, second by use of
sand filtration galleries for river water.
It will be observed that the committee
placed protected deep driven wells
first, and that was done advisedly.
But it is now urged that as sand filter
galleries have been successful else
where we had better do nothing until
the Chamber Of Commerce investigates
this latter process. Of course sand fl
tration has been successful. The
Record Union" has frequently SO
stated. But it is disingenuous to con-
vey the idea that because sand filtration
elsewhere has been successful it might
also work for city situated as is this,
or that it will pay to investigate q. mat
ter the literature of which is so prolific,
and concerning which system engineers
have written so freely.
First let US understand what sand fl
tration is. To condense the definition
of Engineer Allen Hazen, whose recent
article on publication Of river water
supplies has attracted much attention.
Sand filters for publication OF munich
pal water supplies consist in general of
rectangular basins, bottom and sides
water tight. Upon the bottom are IN
derdrains surrounded and covered with
small stones. then gravel, and finer
gravel, and finally deep layer of mod
erately fine sand. The river water IS
taken in over the sand several feet
deem Tho 1,pdard inc popnaof With
the reservoir from which the pumps
draw the water for service supply and
thus an extremely slow, steady, down
ward passage of water is induced. The
matters taken up out of the water by
the sand. gradually accumulate until
its pores are so far filed with them
that the water will not pass in sufficient
quantity to meet requirements 1t IL
then necessary to draw the water off
Of the top, and scrape the upper layer
of sand, which contains the greater
part Of the matter removed from the
water. Eventually it is necessary to
renew the sand as scraping rapidlv
reduces it's thickness. Such filters are
constructed in groups so that a part
can be shut off for cleaning while 9TH
ers operate. Some filter galleries are
built with earth entertainments. but the
best are of solid masonry. We may
add that some have been built with
the filter sand in walls between the fl
ter reservoirs but these are not very
successful since they operate very
slowly, and are best adapted to the
publication of sewage
The report in question does name
cities in Europe and two in America
where sand filtration is successful. It
likewise refers to more cities and
towns where subterranean water sup
plies have proved successful and all
that are desirable. The city nearest
to Sacramento in size having such
wells Is Lowell, Massachusetts. But
the report refers to no river water in
use from stream or streams such as
supply Sacramento; there is no instance
cited of river of such slight volume
- either the Sacramento or the Amer