Mr. DALLYN. I am the provincial sanitary engineer, attached to the
Provincial Board of Health of Ontario.
Mr. TAWNEY. Have you anything to add to what Dr. McCullough has said
regarding the policy of the Province with respect to the purification
of sewage and water for domestic and sanitary purposes in these
boundary waters?
Mr. DALLYN. There is one matter, I think, that is worthy of further
note, and that is as to whether it would be any advantage to either
the municipalities, the Provinces, or the States, to be restricted,
as they are in the report of the commission, to a specific method
of meeting the commission’s requirements. There seems to be some
doubt as to the proper way to interpret the reference--as to whether
the commission is supposed to report some definite way in which a
standard is to be attained or whether the two Governments meant
that a prescribed standard could be reached at a reasonable expense
through at least one method. Speaking as an engineer, not as the
engineer of the Province, I would say we do not want to be hampered
by any restriction in that respect on the part of the commission.
We do need a standard of purity for sewage effluents. It is very
necessary. We can hardly advance any further without one, but we do
not want to be hampered by any particular way of arriving at any
desired result. As to whether we will adopt two hours’ sedimentation
and Imhoff tanks, or a different type of tank, and one, two, or four
hours’ sedimentation is a question that requires study for each
separate municipality. It will depend upon the character of the local
sewage. And with the developments that are taking place in sewage
disposal it is quite conceivable that half an hour’s sedimentation
may be a practical limit, with some particular type of tank. We do
not want to be tied down to two hours’ sedimentation. And then as to
the method of sterilizing the effluent, your report indicates that
bleaching powder, or liquid chlorine, will be the agents to effect
this. Possibly we will not want to be hampered by a provision as to
these. The experiments at Milwaukee indicate that a higher bacterial
removal than you are calling for on these waters can be obtained by
aeration of sewage by the activated sludge process. This method may
not be practical at all centers; it will be practical at some.
That is just the position, I think, that most of us engineers will
take with reference to your report upon remedial measures. We are
very much in sympathy with the effort toward setting a standard of
purification for these boundary waters. It is needed. Some of us
feel that the only feasible and practical way of accomplishing the
desired end is by standardizing the sewage effluent, by saying just
what percentage of matter in suspension you want removed and what
bacterial removal you want. I think the sewage treatment standards
suggested by Prof. Phelps are practical ones and will occasion very
little disputing.
Mr. MAGRATH. You do not want to be hindered from going as far as
possible?
Mr. DALLYN. We certainly do not, sir. As to the construction and
location of interceptors, of course, it is recognized by the
engineers that the commission has had a very difficult problem,
and that, with the time available, they have made a very valuable
report as to the feasible way of handling the question, but there
are a great many studies that will be required to be made before
a municipality should be tied down to any particular route. Your
proposal may show the natural route to utilize, but there might be
difficulties in construction which can not be anticipated, without
a great deal of survey work, by testing the substrata, finding
what is below, whether sand, rock, quicksand, or clay, which might
be overcome by deviating from the prescribed route, even though
the excavation were heavier. Surveys can not be made in a short
time. I feel also that our municipalities heretofore have not had
appropriations with which to make investigation as to whether
the routes suggested by you are practicable. The money that the
commission has expended on this work, of course, is not adequate to
make a very minute survey; and when you realize that in order to
examine this report properly each of these municipalities has to
spend from $10,000 to $20,000 you realize that it is quite a large
undertaking for them to do at a very short notice. It is work that
will require probably a year to investigate. I believe that is all I
desire to say.
Mr. POWELL. You mean, by further investigation, having soundings and
test pits along the route?
Mr. DALLYN. Oh, yes; and by cross sections of sewer, whether it is
cheaper to use brick, or concrete, or vitrified block. There is a
good deal of research work to be gone into before deciding upon work
costing large sums of money.
Mr. POWELL. You speak of the purification of the effluent up to a
certain standard. Would you have that standard fixed without regard
to whether the effluent is flowing into a small or large stream? Can
you fix it absolutely, without regard to the size of the stream, or
the quantity of water that was in the stream to dilute it?
Mr. DALLYN. The sedimentation part of it should be fixed absolutely.
I do not see any difficulty in doing that. There appears to be no
practical or structural difficulty in requiring a certain percentage
removal, or a given number of parts per million, of residual
suspended matter. As to the number of bacteria to be removed, I think
that could be more flexible, depending entirely upon the use the
stream was to be put to, whether as a channel of commerce, or used
largely as a pleasure resort, or whether it had no particular value
in either of those spheres. We have in our Province a great deal of
trouble by reason of townships complaining against the discharge or
raw sewage, or even treated sewage, from some of the municipalities,
saying it affects cattle. It is a disputed matter, but they certainly
have the law on their side, and can compel the municipalities
to purify to a much greater extent than some of you might think
advisable.
Mr. POWELL. What is the growing consensus of opinion in respect of
the purification of the effluent before allowing it to go into the
stream?
Mr. DALLYN. Well, there seem to be two schools--the school of cranks,
asking a high standard, and the conservation school, who want to
use our natural resources to the utmost extent, and who sometimes
overlook some of the changing factors which are not usually taken
into consideration. I belong to the school of cranks, as I told you
before, and I would like to see some better standard adopted than
might immediately appear necessary, as in education we require to
learn more than our vocation appears to demand when measured by
practical methods of the conservation school.
Mr. POWELL. Great Britain seems to head the movement in purification
of streams.
Mr. DALLYN. They have much smaller streams.
Mr. POWELL. It is a different problem, on account of the different
quantity of water in the streams.
Mr. DALLYN. They lack the water-supply problem, and have to treat
the sewage from the æsthetic point of view more than any other. I
have in mind the ability of the stream to take up the putrescible
matter, without giving out odors. In places where several centers
must utilize the same stream there must needs be a more intense
purification than where one center only enters it. With your problem
the purification as to bacterial removal will have to be some
function of the population in the congested centers. In other points,
like Sarnia and Port Huron, the bacterial degree of pollution is not
very heavy, not reaching the 500 standard Prof. Phelps recommends as
being considered a contravention of the treaty, and the function of
population does not amount to very much, so here you would have to
treat it very much better than you apparently need. As a rule, when
you use chemicals to disinfect sewage, you get no action at all until
you remove about 60 per cent. You get a 60 per cent removal or you
get nothing. It seems to be inert; and then you have to increase your
quantities till you get up to 100 per cent removal, the last 10 per
cent taking almost half as much again as the 90 per cent.
Mr. POWELL. Your idea is that under no circumstances should there be
any discharge into the large or small stream without purification to
the extent of sedimentation?
Mr. DALLYN. I believe our civilization has reached a point now where,
as far as self-respect goes, we are required to separate the gross
solids from the liquid matter before discharging them into any stream.
Mr. TAWNEY. Do you desire to be heard at this time, Mr. Sloman?
Mr. SLOMAN. Not necessarily at this time, but at such a time as is
convenient to the commission.
Mr. TAWNEY. Do the representatives from any of the cities on the
United States side wish to be heard before taking recess?