259
Pipe line,
CHEMICAL ANALYSIS.
Lie No. 7.
pysi cal
Appearances.
Colour and
.Transparency. .
Yellowish but clear.
Smell.
None.
11.600
2 000
2.000
4 000
2.130
0.008
0.023
0.104
N i l .
Quantitative.
,
• •
. . Parts per 100,000
Total solids
Temporary hardness .. .. Do. do.
Permanent hardness
..
• •
Do.
do.
a hardness ..
..
..
Do.
do.
brine
•
• •
• •
Do.
do.
ammonia
,
. -
• •
Do.
do.
Al u mi n i o d
ammonia.
• •
• •
Do.
do.
xygen absorbed (Tidy's Process) ..
Do.
do.
Titrates . .. .. Do. do.
Qualitative.
rites
. .
. .
.
. ,
..
Phoshates • • - • •
phasphates
..
• -
• •
poisonous metals...• •
• -
/Ca.
Pres ent
N i l .
Nil.
REPORT.
I. Supply channel to the Sholavaram lake.—This source is very highly polluted ; it contains foecal bacilli in •01
cc . The bacilli present are undesirable ones. Chemically the water is a bad. water. It contains 13° of hardness ;
are 7 . 8 parts per 100,000 and ammonias are high.
II. Sholavaram lake.--The water is improved on that of the feeder channel ; fœcal bacilli are present in 5 cc. ; bacilli
not so objectionable. Chemically the water is superior to the feeder channel, it is much softer 6° and in. other respects it
better. Evidently the lake water is a mixture of channel water and surface rain water ; if this were not the case the analysis
samples (I) and (II) would he almost identical.
III l. Sholavaram channel (that is, the channel from Sholavaram lake to Red Hills lake) .—The water in this channel has
dently received additional pollution of a most undesirable nature ; fœcal bacilli are present in •01 of a cc. Chemically the
is practically the same as sample II.
IV. Boosikal channel —This supply contains a bad water both chemically and bacteriologically ; foecal bacilli are
at in 1 cc , , but the pollution is recent and dangerous.
V . Maclean's channel.—This source is also a very doubtful one. It contains fœcal bacilli in 1 cc. Chemically
water is very bad ; it contains a lot of solid 68 parts, chlorine 11 .36 parts per 100,000 and it is also very hard 26°.
The great permanent hardness and the amount of chlorine suggest pollution by sea water ; but this is not likely.
VI. Red Hills lake.—This is a mixture of all the sources and a lot of rain water from the lake catchment area.
a long series of analyses the lake is after rain very badly polluted, but now settlement and sunlight have improved
considerably, fœcal bacilli are present in 5 cc.
Chemically the water is a soft water 4°, but shows signs of considerable pollution.
VII. Two samples from the town pipes show a very decided falling off in the quality, the water owing to entering the
fœcal bacilli are present in 1 cc. and those of a very undesirable nature are found. 'These are either added in the open
or breed in the silt in the pipes. Chemically the pipe water is bad ; alt the indications of animal pollution have
e a s e d
as compared with the lake water.
General remarks. —The water-supply of Madras is bad from start to finish. The catchment area of the lake is
conservel and thousands of cattle graze in it daily ; the feed channels of the Red Hills Lake all bring in water inferior
q u a l i t y t o t h e l a k e w a t e r ; t h e s e c h a n n e l s a r e f r e e l y p o l l u t e d . T h e g r e a t s a f e g u a r d i s t h e s t o r a g e i n t h e l a k e i t s e l f .
upset by 7 miles of open channel which is polluted and also by silt and probably leaks in the service pipes.