KING INSTITUTE, GUINDY, FOR 1927-28
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It would appear from the results of analyses given in Table IV that all except
the installation at the Waterton Estate belonging to the Binny Mills Co., Ltd.,
turned out an unsatisfactory final effluent. The standards fixed for satisfactory
effluents being—
Albuminoid nitrogen ...
...
0.2 parts per 100,000
Oxygen absorbed in 4 hours
...
...
2.0
"
100,000
Suspended solids
...
...
...
3.0
" 1 0 0 , 0 0 0
The unsatisfactory nature of the final effluents in Carnatic Mills and.
Buckingham Mills might be due to the chemical nature of the sewage dealt with
while in other cases want of supervision may be the cause.
Analyses of special water samples such as the Cooum and the Buckingham
Canal were also made, samples being drawn from different points from one end to
the other. The results show that certain places are heavily polluted owing to the
dumping of nightsoil.
The Analyst and his staff visited Kodaikanal in May 1927 and March 1928
to carry out analysis of sewage and effluent from the installations erected there.
In May 1927, the Presentation Convent installation was the only one in operation
while the Boyer Hall and High Clerc Works were under construction.
The results of examination of sewage and effluent conducted for over a week
showed that the sewage was of a strong character and the final effluent was not
satisfactory. By March 1928, some improvements were made by the addition of
a new filter bed and the pipes leading the septic effluent on to the filter bed were
well regulated so that even distribution of the septic effluent throughout the area
of the filter was effected. Though this improvement gave better results than
during the former period it was not up to the standard selected. This might be
due to the short period of working of the filters. Better results can be expected
when the filters are more mature.
The Boyer Hall and High Clerc installations were only recently put into
operation and though the results of analyses so far conducted show only unsatis
-factory final effluents, further analyses after longer working might show better
results.
Madura was visited in June 1927 and March 1928. At the Madura Mills
there are two large septic tank latrines with percolating filters dealing with the
sewage of about 7,000 employees at the rate of 11 gallons per head per day. In
connection with the Madura Mills Companies settlement for their European
Assistants near Kochadai there is a septic tank installation and a percolating
filter with revolving sprinkler. There is another domestic septic tank installation
of the Madura Mills Company at Pasumalai.
The installations at Kochadai and Pasumalai gave satisfactory effluents.
The final effluent of the Madura Mills installation though better than at the first.
visit was still unsatisfactory which may be due to the fact that the filter beds
were in use alternately, one working in the morning and the other in the evening
and so one filter bed at a time received the effluent from two tanks which probably
overloaded it.
Too much accumulation of sludge in the septic tanks reduce the effective
capacity of the tank and this was noticed on both the occasions of the Analyst’s
visit.
The Pasumalai High School installation gave unsatisfactory results owing to
very small quantity of water used for flushing latrines. The effluent smelt more
of urine than. sewage which is borne out by the high figure for the ammonacal
nitrogen.
(C) Observations on the viability of ankylostome ova and larvæ in septic tanks
and bacterial filters.
This piece of work was taken up at the suggestion of Lt.-Col. King to find
out whether septic tanks and bacterial filters could be of use in preventing
ankylostome infection.
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