The daily dispatch. [volume] (Richmond [Va.]) 1850-1884, 1869-09-24

ready impure water pcrceptibly. From
the testimony before rs, and from the ex-
perience of the cities of Boston, Albany,
New Haven, Paris, Berlin, and London,
your committee believe that the water from
the Mississippi river, if stored in reser-
voir exposed to the summer heat and sun,
would produce the same result as in those
cities, and would not only become unpala-
table, bat would become actually injurious
to the health of consumers"
The same opinion is held by all the most
eminent engineers and chemists of Eng
land. Hawksley says: Vegetation, as
source of impurity, depends upon the time
during which the water is stored. II the
water moves through the reservoir with ra-
piditv of course it does not collect that
amount of vegetation which it would collect
if it remained stagnant in the reservoir Tor
any considerable period of time; that is
obvious it is practically so, and it is ac-
cordinr to common sense" Beardmorc
saws {" Water, when comparatively stag
nant, tends to generate animal and yegeta-
bic life. can only speak of it as regards
the taste and certain effects. No engineer
wishing 10 supply town with water would
CDOOSC SUCH IL VI co.
If the committee tell us that they do not
Intend to make the reservoir which they
propose so high at first, but to raise its sides
to only a moderate height at present, SO
that the body of water will not at first be so
deep, can only give them the opinions OF
Vetch and Leslie. The former says: II
shallow reservoirs are exposed to the heat
of the sun in summer they give rise to We
retable and animal life" And the latter
saws "I do know exactly what depth is
required in reservoir to prevent vegcta-
ton. have known considerable vegetation
in ten feet water"
These high authorities arc sufficient to
show conclusively that the reservoir pro-
posed by the committee in their report will
not improve the d" quality" of the water.
| AS | have already taken up so much Of
your valuable space, will try and abbrc-
viatc my further remarks Us much as pos
sible.
Whatever difference of opinion there may
| be among engineers as to the modtS ope-
randi of purifying river water, it is con-
ccdcd by all that the ,cater should be puri-
fed before entering the p1nnpS; otherwise,
there will be added to the cost of purifying
the wear and tear Of, the pumps.
The most feasible plan to purify river
water before entering the pumps is the plan
adopted at Germantown and West Phila-
dclDhia in 1851 and 1862, and which was
afterwards, in 1859, recommended very
highly for the Philadelphia Fairmount
Water Works. AT Germantown the supply
of water is procured from the Toolpahockin
creek, which is damned up 80 rs to form q
store or subsidiary reservoir at the foot OF
Toolpahockin street. A sluicc-way is con-
structed in the DAM so that, during heavy
| freshets, instead of allowing the superfu-
Gus water to flow over the dam it is drawn
from the bottom or deepest part of the
pool, and the impurities Of the water thus
carried off through the sluice-thc pnrcr
water only passing to the works. 1t is thus
| found that at these works-which are sup
piled by Il small stream into which much
that is Objectionable is drained-that while
at the bottom of the pool the water may be
totally unfit for use, being sometimes even
offensive to the smell, at the same time
within few inches of the top it is limpid
and perfectly free from taste or odor, and
the town is supplied with excellent water
from this sourcc at all seasons Of the year.
IhlS plan, as DelOre Stateu, mus IecoIh
mended highly in Philadelphia in 1859 for
the Fairmount Water Works, and think
it the most feasible for our works, as the
water here is only turbid for Il few days
during frcshcts. The turbidncss which We
have here is caused BY the finely divided
particles of clay held in suspense. The
precipitation Of these would be facilitated
both by the water being kept in compa-
ratiye state of rest and by the sluice; which
latter would not only facilitate precipita-
ton, but also prevent the sediment collect
ing at the bottom.
/ will conclude in the words of NJ. Il.
Grimaud de Caux, in his celebrated work
"Des caux publiques ct dc leur appllca'
ton aux besoms des Grandes Villos. DIES
communes, ct des habitatiOns ruraies'''
After reviewing all the different modes at
tempted to purify water on large scale,
he says: " We will lay aside the question
of fltering on large scale, which will be
for inventors forever the pendant to the
mathematical problem of squaring the cir
Gle, with this difference, that the inventors
of the latter require no outly of capital,
while the former run the risk of running
the corporations for whom they act"
Your obedicnt servant, RICHMOND.