OPINIONS regarding Sewage Treatment
DR. GILBERT FOWLER, F.T.C., F.C.S. (Superintendent and
Consulting Chemist of the Manchester Corporation Sewage Disposal Works)
in giving evidence upon Dibdin’s slate beds, said :-
"The result of examination showed that at no point did
the deposit, although teeming with bacterial life, possess a really offensive
smell. In general, it rather resembled seaweed. The presence of numerous
red worms showed that the conditions were mainly aerobic. Apparently
similar changes were taking place in the beds to those occurring in well-manured
soil on the banks of slightly polluted rivers. . . I am able to state my
confident opinion that the slate process is scientifically and economically
DR. SIDNEY BARWISE, D.Sc., D.P.H., (Medical Officer of Health
for County of Derby), in his quarterly and annual reports to the County Council,
"The sludge nussance is one which has called for an
enormous amount of attention from experts. Mr. Dibdin has, during the last
two or three years, perfected a system, which I have been to inspect. . . The
result is that the whole of the organic matter in the sewage is digested by
the worms and other living creatures and converted into humus. . . The
Dibdin slate bed consists of a shallow tank packed with pieces of waste slate
laid horizontally, each layer being 2 in. above the one below. . . . When the
bed is in full working order the slates are covered with a rich dark humus. Of
course, there are bacteria, but the chief organism present is the Tubifex
Rivulorum; in fact, the beds I saw at High Wycombe were almost pure colonies
of these creatures, with nests of their eggs. In addition, there were other
larger worms, annelida, and their larvae, insects I could not classify,
crustaceans, arachnida, and innumerable amoebae, infusoria, and other
protozoa. Under the microscope the lifeless solid matter appeared in the form
of short columns, of the same diameter as the intestine of the Tubifex
Rivulorum, and I have no doubt that the bulk of the sludge on the slates
consists of the casts of the common river worm
—it is, in fact, humus. . . First, all the
decomposable organic matters in it are digested, and it is perfectly inodorous—in
fact, the only smell which I was able to distinguish by applying my nose to
the beds was the good smell of the earth. The result of this is that in the
future it will be possible to put sewage works nearer to dwellings than
previously would have been regarded as desirable, and Authorities with a
sludge nuisance have a simple mea s of getting out of their difficulty. .
. . Here, then, we have what I believe to be the safe conclusion to the old
controversy between the advocates of contact beds and percolating filters.
What is required is :—(1) a subsidence tank to separate the grosser
suspended matters (i.e., road grit) ; (2) primary contact beds of
slates in duplicate, to produce an inodorous and easily disposed of sludge,
and at the same time a tank effluent which is already aerated; (3) a
separating tank, to catch humus, and so save filters; (4) a percolating
filter, to finally oxidise the organic matter in solution."
Report of Meeting of the Institute of Sanitary Engineers from
"THE SURVEYOR," 1909.
MR. A. J. MARTIN, M.I.C.E., says: "They all
believed that Mr. Dibdin had discovered the North Pole in this matter and were
willing to give him every credit for his attainment."
Excerpt from letter from DR. SIDNEY BARWISE, M.D. (LOND.),
B.Sc., County Medical Officer of Health, Derbyshire, to Messrs. SAUNDERS &
SAUNDERS, Civil Engineers, 39, Victoria Street, Westminster.
September 9th, 1910.
WHITSTABLE SEWAGE WORKS.
I have carefully gone through the two reports submitted by
you and the sketch plan of your scheme for treating the Whitstable sewage. The
conclusions I have come to are that your scheme carries out the suggestion made
in the report of the Local Government Board. It complies with all their
requirements, and it is drawn up on lines which I believe the Kent County
Council would approve, as also would those interested in the oyster
Looking at it from the point of view of oyster culture and
the amenities of the place as a health resort there are six distinct lines of
defence against contamination of the foreshore and the shell fish:-
1. The slate beds in which the solid matter is digested
by minute worms, infusoria and other organisms.
2. The humus tanks separating the solids discharged
from the slate beds.
3. The percolating filters, which are the most
practical methods of oxidising sewage yet known.
4. The humus tanks separating the solids in the
effluent from the filters.
5. The sand filters such as are constructed for the
filtration of water.
6. The storage of the sewage as suggested by the Local
Government Board so that it may be discharged on the ebb tide.
I have no hesitation therefore in saying that you have taken
every possible precaution against the contamination of the shell fish which is
yet known to science.
Excerpt from letter from MR. CHAS. S. BALL, Corporation
Sewage Works, Manchester, to MESSRS. SAUNDERS & SAUNDERS, 39, Victoria
September 9th, 1910.
In reply to your enquiry of the 7th inst., re scheme
of sewage disposal for the Urban District of Whitstable.
I have most carefully considered the whole of the
information put before me, After consideration I feel convinced that the
methods you propose to adopt in the sewerage of the town will be most
efficient, whilst the methods you propose for the purification of the
sewage includes everything that modern science can suggest.