Hearings of the International Joint Commission in re remedies for the pollution of boundary waters between the United States and Canada

by International Joint Commission

Mr. Magrath. I thought you might bring that out.

Prof. Phelps. It was not so simple to determine just what——

Mr. Powell. Pardon me. You say that the burdens imposed by the treaty on communities like the city of Buffalo are not so great as the law of the United States or the law of Canada would impose upon these communities. Is that what you mean?

Prof. Phelps. No, sir. May I return to that point later? I was about to say that it was not self-evident in the terms of the treaty and the reference just how much pollution could be permitted without permanent and definite injury to the health and property of those on the other side. It was necessary to seek advice upon that point, and it seems to me that that point is the only one susceptible of any difference of opinion. It must be understood, in the first place, that rivers of this sort can not be maintained in their pristine purity. They must serve for the natural drainage of populous areas, and they must be polluted to a greater or less extent. Furthermore, the city sewage can be treated to almost any condition desired. We can make drinking water out of it if we want to, but the cost would be prohibitive. We can purify it to any degree varying from mere screening up to the drinking-water standard.

Now, how much pollution shall we permit in these rivers—how much ought we to permit, considering the economic aspect of the situation, and also to comply with the obligations of the treaty? Upon this point the commission sought the best engineering advice available, and obtained a definite statement of a limiting standard of purity beyond which it was deemed unwise to go for drinking-water supplies.

Now, there is no question here of using these supplies in their raw state; it is assumed to be the duty of all cities using these rivers to purify them to the best of their ability. It was only proposed that the rivers should not be polluted beyond a fit condition for further purification for domestic purposes. It is the most moderate and conservative standard that we can possibly propose.

Having arrived at this point of departure with respect to a standard, which is capable of some flexibility, and is, after all, only an opinion, the remainder of the work was purely an engineering study of the means necessary to accomplish the desired results. Those means, as I have stated, we have studied in some detail. We are satisfied that our figures are correct. We are satisfied that the city can do what has been recommended to the commission within the estimated cost. As I have stated, we believe they can do it for less money. The progress of sewage purification and the necessary additional engineering studies will undoubtedly bring about further economies. We are content, however, to rest upon the figures given. We believe that those figures are a reasonable and justifiable burden to impose upon this city.

Now, as to the standard itself. That is, of course, open to discussion. It may be too severe. The city of Niagara Falls seems to be quite content to purify this water as it is to-day. Other cities are not. There are upon record several cases of water filters or purification plants, treating water worse than our proposed standard, which have on occasions failed. The best engineering devices fail at times, and the water filter, or a sterilization plant, is at most a fallible engineering device. It is fairly satisfactory, but at times it fails, and it is our duty as sanitarians to provide a raw water for treatment at such plants of a character which will not impose too much of a burden upon the water plant, which will not reduce the margin of safety below a reasonable point.

We had all these matters in mind in fixing the standard alluded to, and if any further discussion is desired as to the reasonableness of that standard, we shall, of course, welcome it.

Capt. Norton’s suggestion this morning that instead of considering the entire cross section, we should consider the fact that the water is naturally better in some strips than it is in others, seemed to me to be a point well taken. Of course that is not a matter that we can deal with in figures. The only way we could handle the matter in figures was to assume that the sewage was mixed throughout the cross section, and it is shown in the report that that is probably the most extreme assumption. It gives us the worst water, because if it is not mixed throughout the cross section, then there are necessarily better and worse streaks than the average, and the better streaks would be available for a source of water supply. On the other hand, the flow of water in streams or lines is a matter which is not capable of definite engineering study. It is a matter which can be discovered only by experimental work on the river, and it is a matter upon which we do not dare to place too much reliance. There are in most rivers changes in the channels, in the drift of the current as effected by the direction of the wind; then various elevations and rates of flow modify the drifts to a certain extent. So I think we should be a little cautious in assuming that there are available at all times streaks of water better than the average. I do not doubt that there are in most cases just such conditions.