7

REPORT OF THE KING INSTITUTE, GUINDY

     Cocanada.—Inefficiency of its slow sand filters has been noted in these reports yearly for 18
years thus Col. Clemesha in 1908 said "the filtered water is very much worse than the storage tank
sample; faecal bacilli are present in 0.3 c.c. This has been found on inspection to be due to sub-
soil water finding its way through cracks in the masonry into the filters." Whatever the reason
the fact still remains that in 1925-26 the filtered water was worse or no better than the unfiltered.

     Dindigul—Another source of supply needs to be established to supplement the infiltration
gallery supply in the hot weather and to obviate the necessity of using polluted water from the
railway station well.

     Ellore.—The slow sand filters are not working properly now.

     Kurnool.—Unfiltered water is added to filtered water occasionally and without authorization.

     Madras adds unfiltered water to filtered water—an economical but hardly a sanitary practice.
This has been done for the last 12 years—an extraordinary state of affairs for a capital town.
Government passed orders directing the Madras Corporation to instal rapid filters to deal with
their unfiltered water. This has not yet been done.

     Salem.—The filtration is defective and has been so for seven years.

     Tuticorin.—No filtration is done despite the heavily polluted nature of the water which has
been reported for five years. Chlorination was advised. No information has been received whether
it is being carried out.

     Vizagapatam.—Repairs to the filters were required, but a year seems an unnecessarily long
time to have them thrown out of action.

     3. Jail supplies.—Details are given in Table XIV. These supplies are all
from wells and except in Cannanore the water has to be chlorinated. Local
investigations are needed to determine why the water should contain so many
coli-form organisms. Chlorination should be considered only a temporary ex-
pedient for water from good wells, because ordinarily such water should be so
good as not to need chlorination. Rajahmundry jail which reported heavy pollu-
tion of its water was visited, and the pollution was found to come from thousands
of bats roosting under a platform low down in the well.

     4. Railway supplies.—Details are in Table XIV. The Bengal-Nagpur
Railway have at last opened a new source of supply at Naupada junction to
replace the old well. Supplies at Pakala junction in the Madras and Southern.
Mahratta Railway and Erode and Podanur on the South Indian Railway have
been adversely reported on for several years. Reference:—G.O.No.2147, P.H.,
dated 22nd November 1925, paragraph 4, orders are awaited on supplementing
the list of railway stations whose water should be examined.

     5. Types of filters.—Judging from the working of filters in various munici-
palities, slow sand filters seem to have given poor results, Mechanical filters,
though they have given good results in some cases, yet in others their results too
were poor usually from defective working. Careful working is essential for the
success of these filters. Infiltration galleries usually fail to deal -with pollution
in flood water, and further some galleries appear to need to be examined for the
presence of cracks, e.g., Guntūr.

     6. Response to advice.—This Institute functions only as an examining and
advisory body and so is not directly concerned with the bringing about of
improvements the responsibility for which rests on local bodies. Yet in its own
work it cannot help but be disheartened by finding that the same defect is
reported year after year without much being done. That this is the case will be
apparent from reading the summaries of reports on municipal water supplies for
the last few years.

(D) WORK FOR THE WATER AND SEWAGE PURIFICATION COMMITTEE.

     1. Water.—The following experiment was carried on from September to
March and still continues. Samples were taken twice a week.

     Idea of experiments.—Many places, e.g., Adoni and Salem, have trouble with
slow sand filtration in the hot weather on account of the large amount of organic
matter present. It was thought that possibly the better aeration received by
the use of a percolating filter with a non-submerged bed might be an improve-
ment. Accordingly the experiment has been the comparison of a percolating
non-submerged filter with an ordinary submerged slow sand filter.

     Periods.—In the first three weeks the percolating filter consisted of four
feet of brick clinker over broken stone. Distribution was by spraying.