ical, followed by a period of subsidence (rest) of the dosed water prior to (2) passage through the sand bed. Were this colored and turbid water to be dosed with chemical and immediately run through the filter tank as must necessarily be the case in a system of the pressure type, it is rather inconceivable that the results would be uniformly entirely satisfactory, although in cases where bacterial purification is not the prime essential and mere physical improvement is what is sought, it is quite possible that with careful management a sufficient degree of the latter might be attainable in this way such as to represent substantial improvement and render the water supply fairly satisfactory to consumers from a physical standpoint.

The fourth proposal, involving permanent abandonment of the river source in favor of an auxiliary supply from Success Pond, has been the object of our recent investigation. According to a report made by Weston & Sampson on this project about a dozen years ago, their conclusion was that this source would provide an abundant supply "for generations to come" but that its utilization would be relatively expensive. The estimate mentioned at that time of the cost of a line to bring this water to the present reservoirs was $40,000, and it is probably safe to double this figure to cover present cost conditions.

Notwithstanding that Weston and Sampson seemed inclined to believe there was no question of the adequacy of Success Pond at that time, we are informed that during 1923 a member of this firm, as a result of weir measurement of the outflow, expressed skepticism,— such outflow at that time being practically nil.

However, the dam then existing on the outlet brook has since been destroyed and at the time of our inspection, a good-sized brook, representing a large volume of flow, was escaping. The inlet, Sucker Brook, was also noted as contributing a large volume of water at this time.

Success Pond, situated in the northeasterly part of Success Township, is a body of water about one and one-half miles long by a half mile wide. The estimated length of a pipe line to connect with Keene reservoir is eight miles. The locality is a wooded wilderness, there being no farm land nor permanently occupied habitations for many miles. There are however at the present time a dozen cottages, or camps, on the shores. Until this year there was comparatively easy access to this pond from Berlin by means of a road following the embankment of a former logging railroad but as a result of storms this road is at present impassable to vehicles.

The shores are generally gravelly but there is some swamp, or marsh, notably at the northerly end and at a place on the southwest

side, west of Sunset Camp. The color of the water in situ is dark and considerable turbidity is in evidence. Sucker Brook, the only feeder of any importance, comes in at about the middle of the east side, while the outlet brook leaves from the northwest side.

Sanitary Aspects

Although there is no possible pollution at the present moment yet it is stated (a) that the road is soon to be rebuilt, (b) that the tract surrounding the pond, most of it virgin forest, is to be cut off at an early date. The first means that the tendency on the part of Berlin residents to utilize this beautiful body of water as a resort will be apt to be more marked as time goes on, while the second means not only chance for some pollution but also a probable substantial reduction in available storage, due to much greater volume of run-off at times of freshets and storms. Nevertheless it is believed that, considered as an auxiliary or feeding source for the present brook reservoirs, there can be no serious doubts as to adequacy of this pond as a supply.

The sanitary arrangements at such cottages as were visited were satisfactory. However in the possible event of the taking over of this pond it would be necessary for the State Board of Health to establish the usual regulations, which latter would necessitate some changes and improvements in this respect, as well also as probably impose some restrictions upon boating and bathing, A fact to consider in this connection is that because of an intervening elevation between the pond and reservoirs, a certain amount of pumping to get this water into the latter would be necessitated.

Quality of Success Pond Water

Accompanying this report is an analysis data sheet giving results of recent analysis (a) the reservoir water, (b) river, (c) four samples collected July 2nd fro mSuccess Pond. It will be noted that the physical character of the latter is quite as inferior as that of the brook water. In fact, in point of turbidity, color, and vegetable matter, the analytical data do not denote a water any better than that of the river. Obviously, to be really satisfactory, this water also must be filtered. Furthermore, although it is said that consumers can always tell by the appearance of a peculiar taste when the river is turned in, yet from the standpoint of mere appearance and content of vegetable matter, as indicated by such samples as we have have received, the present reservoir water is little if any superior to that of the river. However, the number of samples examined by this department is relatively very small and it is quite probable that at times the river shows a very substantial turbidity.

Conclusions

It is very difficult to determine just what is the best course for the city to pursue. It is obvious (a) that the brook reservoir water is of unsatisfactory physical quality and ought to be filtered, (b) that the necessary additional supply whether taken from the Androscoggin River or from Success Pond will also require filtration, for the first this being imperative and for the second highly advisable.

Beyond insisting that if the river source is to be continued this must be with the application of rapid gravity type fitration and chlorination, this department is rather reluctant to advise. Whatever course is finally decided upon must necessarily be as a result of a thorough study of the relative cost aspects involved, and, as stated, this is something into which we are not called upon to enter. In this connection the advice of a thoroughly competent and at the same time disinterested consulting sanitary engineer should be worth having by the city. It may be pointed out that this is not only a very important matter but one involving the expenditure of a large sum of the tax-payers' money, and it will prove money well spent to have the best engineering advice obtainable.

Incidentally it is well to point out that the results of analysis of a thoroughly competent and at the same time entirely disinterested consulting sanitary engineer should be worth having by the city. It may be pointed out that this is not only a very important matter but one involving the expenditure of a large sum of the tax-payers' money, and it will prove well spent to have the best engineering advice obtainable.

Incidentally it is well to point out that the results of analysis of samples suggests that there is considerable contamination of the mains by deposits of iron, a circumstance which would serve in material degree to nullify the improved results due to filtration. In the case of the city of Keene, which is now installing fitration, it was found that the street mains were in very bad shape due to the cause. The cleaning of such by the special process employed is said to have nearly doubled their carrying capacity.

Any additional information or advice which may be desired will be promptly given.

Very truly yours,

CHARLES D. HOWARD, Chief of Division

Supplementing the above report, the following communication was transmitted in response to a request for further information:

August 10, 1925

Hon. Joseph A. Vaillancourt, Mayor

Berlin,

New Hampshire

Dear Sir:

I desire to acknowledge receipt of your request for further advice on the water situation, as transmitted to me through a recent letter of your health officer, Mr. H. F. Leeds.

In the first place perhaps I ought to point out that it is no function of this department to instruct a municipality as to which one of a number of plans under consideration it should adopt. Our concern, of course, is from the sanitary, or health, protection standpoint and in such capacity we can refuse to approve any plan which we feel may not afford an entirely safe supply. On the other hand, approval of a given proposal advanced by the city by no means implies that such is the best proposition, all things considered. That is something each town and city must decide for itself.

However I am very glad to give you such additional information and advice as I can. In this connection your question, as transmitted to me by Mr. Leeds, was as follows: "What would you favor the use of Success Pond with a pressure filter; or the use of the Androscoggin River with appropriate filtration and treatment? You are not to take the financial point into consideration at all."

As a matter of fact, in the ultimate determination of this question it is impossible to avoid considering the financial aspect, for the reason that it is bound to make very considerable difference, financially, whether the pond and reservoir system (which would be mainly gravity) is adopted, or whether the present reservoir system, with pipe lines, dams and other property rights involved, is to be virtually junked in favor of a pumped system derived entirely from the River. This is something calling for an intimate study of costs, a study which I think ought to be made, regardless of how much or how little you may be influenced by the figures in the final selection of the plan to be inaugurated.

I take it however that so far as I am concerned you merely wish me to advise you which would give your citizens the more satisfactory supply, i. e., prove most satisfactory in the end, regardless of immediate costs, (a) the pond-reservoir source under mechanical fitration of the pressure type, or (b) the river source with a modern system of mechanical fitration employing filters of the gravity type, in conjunction with chlorine.

Frankly I must say I believe that in actual practice there would be times, under either arrangement, when your consumers would

find some criticism. That is, I mean that unless the river plant had not only continuous skilled supervision but the most conscientious attention on the part of an intelligent operator, there would be times, such as under flood conditions, when there would be some tendency to deteriorations in the physical quality.

But, whereas a continuously good supply from the river would be practically merely a matter of good management, the situation would differ from this as to the pressure-filtered pond water in that I believe it would be impossible with such a treatment, even with the most intelligent and careful supervision possible with such an arrangement, to turn out continuously water that uniformly exhibited the low degree of color, turbidity, and freedom from odor and tastes such as you would be entitled to expect from such an installation. On this point I can only repeat what I stated at our conference July 1st, which was that the pressure type of filter is very generally recognized by water supply engineers as primarily one adapted to and mainly employed for industrial use and that it is poorly suited to the treatment on a municipal scale of water for domestic use.

For this I gave a number of reasons. One of the most important of these is that with both types of filtration the use of a coagulating agent is indispensable for proper clarification as required in advance of the actual filtration. With the regulation type of gravity plant there is always a coagulating basin provided, which permits of opportunity for settlement of the sediment and precipitated matters after the coagulating agent has been added and before entering the filter.

With the pressure type no such basin or chamber is provided. The coagulant is taken up by the water from the "pot" set in on the pressure line and the treated water goes immediately to the filter. In the gravity type a detention period of three to four hours is recognized as necessary for the best results and this is now generally provided in all municipal practice.

In this connection it is interesting to look up to the extent of the use throughout the country of filters of the pressure type. Referring to the 1925 edition of the "Municipal Index" it will be found that of all of the cities of the country of 5000 or more, just one only, viz, Lynchburg, Va., is listed as having a pressure-filtered domestic water supply. It is true that there are other places which use this kind. Some of these are under 5000 while others have this space left blank in the "Index", probably because of no returns received.

Nevertheless it is fair to say that Lynchburg's is the leading illustration of one of the few municipal plants of this type in the coun