Book /ye> ^ ^ tCfO% Issued by the lommission of New York ►09 DIGEST OF DATA COLLECTED BEFORE THE YEAR J908 RELATING TO THE SANITARY CONDITION OF NEW YORK HARBOR H.%K.L { P.v,fc Prepared and Issued by the Metropolitan Sewerage Commission of New York 1909 MARTIN B.BROWN * PRESS*' -\ ^ h -h <3 > ,(.-V^^ €^ :ri^'^'7 J Digest of Data Collected Before the Year 1908 Relating to the Sanitary Condition 1 of New York Harbor s FOREWORD It is the purpose of this report to make pubHc a digest of the analytical data available up to 1908 relating to the sanitary condition of the waters of New York Harbor. The object in undertaking the study of these data was twofold : First, to turn to account the work which had already been done, so that further investigations could be based upon it; and, second, to present the essentials of these technical facts in a form suitable for the information of those interested in the subject. The investigations here included contribute materially to an under- standing of the conditions which follow the discharge of sewage into harbor waters ; but it must be understood that these data are not pre- sented as a basis for conclusions, further examinations of the water of New York Harbor and the procurement of additional data being now in progress. The first official body to attempt a comprehensive investigation of the conditions attending the disposal of sewage in the metropolitan district was the New York Bay Pollution Commission. This commission was appointed by the Governor of New York in 1903 and existed until 1906. The members were : Daniel Lewis, President ; Olin H. Landreth, Myron S. Falk, George A. Soper and Louis L. Tribus, Secretary. The New York Bay Pollution Commission pushed its studies of the water as far as its appropriation would allow, and its two published reports form the basis of the analytical work done since. The Metropolitan Sewerage Commission of New York was created in i(X)6 to carry on the work recommended by the New York Bay Pollu- tion Commission. This commission was appointed by the Mayor of New York in accordance with an Act of the State Legislature, Chapter 639, Laws of 1906 (amended by Chapter 422, Laws of 1908). The original members were : Daniel Lewis, President ; Olin H. Landreth, George A. Soper, Matthew C. Fleming and Andrew J. Provost, Jr., Secretary. On November 5, 1906, Commissioner Fleming resigned and Mr. James H. Fuertes was appointed to fill his place. In January, 1908, the commission was reconstituted and it has since consisted of the undersigned. Until the beginning of 1908 the work of the Metropolitan Sewerage Commission consisted chiefly in the collection of analytical data, little attempt being made to extract the useful information from the reports of the analysts as the work progressed. The work done since January, 1908, under the present Commissioners is not recorded in these pages, but when completed, will form the subject of a later report, which it is hoped will reconcile the contradictions con- tained herein and in the light of fuller information tend to a better under- standing of the conditions as they exist. In addition to the work of the New York Bay Pollution Commission and the Metropolitan Sewerage Commission, various other studies of the waters of New York Harbor made for special purposes are referred to in this report. The actual work of analysis in these investigations has been well done. The analyses for the New York Bay Pollution Commission and the De- partment of Water Supply, Gas and Electricity were made in the municipal water laboratory at Prospect Park, Brooklyn. The methods of the analyses were those of the committee on standard methods of water analysis of the American Public Health Association. During the work of the Metropolitan Sewerage Commission before 1908 Mr. George C. Whipple and Dr. Daniel D. Jackson served as con- sulting analytical experts to this commission. The scheme of sampling, the lines of investigation and the interpretation of the results for the New York Bay Pollution Commission were due to a committee consisting of Commissioner Soper. The direction of the work done by the Metro- politan Sewerage Commission up to 1908 was in the immediate charge of Commissioners Landreth and Provost. The analyses for the Metropolitan Commission were performed in a laboratory fitted up in the Aquarium building through the courtesy of the New York Zoological Society, and were made mainly by the following staff: Mr. David S. Merritt, Dr. Payn B. Parsons, Mr. P. S. Miller. For a short time Messrs. Charles F. Breitzke and Eric T. King were engaged on the work. Metropolitan Sewerage Commission of New York, George A. Soper_, President; James H. Fuertes^ Secretary; H. DE B. Parsons, Charles Sooysmith, LiNSLY R. Williams. TABLE OF CONTENTS Section I. Investigations Made by the New Yorl^ Bay Pollution Commission in 1904 and 1906 PAGE THE INVESTIGATIONS OF 1904 9 A. Bacterial Results 10 1. Bacteria in the Water 10 (a) First series of samples 10 (b) Second series of samples 11 (c) Third series of samples , 11 (d) Fourth series of samples 12 2. Bacteria in Shellfish 13 B. Chemical Results 13 C. Studizs of Salinity 15 THE INVESTIGATIONS OF 1906 16 A. Bacterial Results 17 1. Numbers of Bacteria in the Water at Different Depths 17 (a) Lower Bay and Narrows 18 (b) Upper Bay and lower parts of East and Hudson Rivers 18 (c) Rivers surrounding Manhattan Island 19 2. Bacterial Conditions in Various Small Arms of the Harbor. 19 (a) Gowanus Canal 19 (b) Lower Bronx River 20 B. Chemical Results 20 1. Chemical Conditions at Different Depths 20 (a) Upper New York Bay 20 (b) Lower Bay and Narrows 21 (c) Upper New York Bay and lower parts of East and Hudson Rivers 21 (d) Rivers surrounding Manhattan Island 21 2. Amount of Oxygen in the Waters of New York Bay and Vicinity 22 C. Results of Sanitary Inspections of the Shores of New York Bay 2s (a) Upper Bay 23 (b) Lower Bay 24 (c) Oyster grounds 24 D. Summary of Conclusions Reached by the New York Bay Pol- lution Commission 25 4 Section II. Investigations Made by the Metropolitan ^^^^ Sewerage Commission in 1907 27 A. Numbers of Bacteria in the Water 28 1. Surface Samples 28 (a) Seasonal variations 30 (b) Disappearance of bacteria from the water 31 2. Numbers at Different Depths 31 3. Diurnal Variations .... 32 4. Relation to Stage of Tide 33 B. Numbers of Bacteria in Solid Matter at the Bottom of the Hareor 34 1. Numbers at the Surface of the Bottom ' . . , 35 (a) Maximum and minimum numbers 35 (b) Variations in numbers. 35 (c) Numbers in water and solid matter compared 35 (d) Localities having large numbers 36 2. Numbers Below the Surface of the Bottom 37 (a) Diminution with depth '. . . 2)7 (b) Variation with locality. 38 (c) Usefulness of these data ' 38 C. Presumptive Test for the Colon Bacillus 39 1. Coli in the Water 39 (a) Prevalence of coh 39 (Id) Absence of coli in deep water 40 2. Coli in the Solid Matter at the Harbor Bottom 40 (a) At the surface of the bottom 40 (b) Significance of results 44 D. Results of Chemical Analyses 41 1. Free Ammonia in the Water 41 (a) Comparison with other results 42 (b) Relation to tide and depth 42 (c) Diurnal variations 43 2. Albuminoid Ammonia in the Water 43 (a) Maximum and minimum results 44 (b) Significance of results 44 3. Chlorine in the Water 45 (a) Value of results 45 (b) Intermixture of sea and land water 45 4. Loss on Ignition 46 (a) Water 46 (b) Solid matter from the bottom of the harbor 47 5. Color of the Water 48 6. Turbidity 5o PAGE E. The Flow of Tidal Currents as Ascertained by Means of Floats 51 1. Methods 51 (a) Object of these studies 51 (b) Behavior of floats 52 (c) Method of observing the floats 52 2. Results 52 (a) Flushing action of the tide 52 (b) Maximum and minimum distances covered 53 (c) Currents near shore and in midstream 54 Section III Investigations Made by the Department of Water Supply, Gas and Electricity of the ^^^^ . City of New York in 1904 and 1905 55 A. Bacterial Results 56 I. Numbers of Bacteria 56 (a) Variations in numbers 56 (b) Complexity of conditions 57 (c) Conditions at bulkheads and pierheads compared.. 58 (d) Relation of depth 58 B. Comparison With Other Results 58 Coli in the Water 59 C. Chemical Results 60 1. Free Ammonia, Albuminoid Ammonia, Nitrites and Nitrates 60 2. Chlorine 60 Section IV. Investigations Made by Charles F. Breitzke in 1906 of the Sanitary Condition of Qowanus Canal 6i A. Sanitary Survey •. ; 61 B. Analytical Results ...;.■..•.. 63 C. Discussion of Data 64 6 Section V. Investigation of the Waters of the Lower Hudson River by the Burr=Hering= Freeman Commission in 1903 PAGE A. Hydrographic Features 67 1. The Hudson River 67 (a) The Hudson as a source of drinking water 68 (b) Depth and width of the Hudson 69 (c) Cubic capacity of the Hudson 69 (d) Discharge of the Hudson 70 2. Tidal Phenomena 70 (a) Tidal ranges in the Hudson 70 (b) Duration of tidal periods. 71 (c) Effect of wind on the tide level 71 B. Studies of Salinity 71 1. The Salt of the Sea 71 (a) Chlorine 71 (b) Mineral ingredients of sea water "72 2. Saltness of the Hudson T2) (a) Changes in salinity ^"^ (b) The underrun 'j'}) (c) Sanitary importance of the underrun 74 (d) Salinity at different points across the stream 75 (e) Changing nature of the problem 75 C. Pollution of the Hudson 75 (a) The author's point of view 75 (b) Method of study ^6 (c) Population on the drainage area ^(i (d) Typhoid rates ']^ (e) Danger of pollution yj Section VI. Investigation of the Condition of the Passaic River by Messrs. Hazen and Whipple in 1906 PAGE A. General Discussion of the Problem by Mr. Hazen 78 I. The Manufacturing Wastes 78 (a) Dye house wastes 79 (b) Wastes from various industries 79 PAGE 2. Condition of the Sewers 80 (a) Capacity and repair 80 (b) Outlets and deposits 80 3. Effect of Diverting Water from the Passaic 80 (a) Extent of the draught 80 4. Conclusions 81 (a) Health considerations 81 (b) Injury to property 81 (c) Recommendation 81 Discussion of the Chemical Composition of Paterson Sewage, BY Mr. Whipple 82 1. The House Sewage and Factory Wastes produced by Pater- son 82 (a) Quantity of house sewage 82 (b) Polluting matters from manufactories 82 (c) Experiments with dye house wastes 83 (d) Brewery wastes 83 2. Results of Analyses , 84 (a) Analyses of sewage 84 (b) Analyses of river water 84 (c) First series of analyses 85 (d) Second series of analyses 86 (e) Third series of analyses 87 Section I. Investigations Made by the New York Bay Pollution Commission 1903 to 1906 THE INVESTIGATIONS OF 1903 AND 1904^= The work of the New York Bay PoUution Commission was the first systematic attempt made to ascertain by means of analyses, the sanitary condition of the waters of New York harbor. Some rough determinations of sulphides had been made many years before which had led experts of the U. S. Coast and Geodetic Survey to conclude that the sewage of New York City might be accumulating at the bottom of the harbor, a few analyses had been made by Mr. G. C. Whipple in connection with studies for an additional water supply for New York and a number of analyses had been made in con- nection with an auxiliary fire fighting service for New York; but the total number of these examinations was relatively small, and they were not intended to throw much light upon the larger problems raised as a result of discharging sewage into the harbor. It may be said that the New York Bay Pollution Commission found little information at hand upon which to base conclusions or to guide it in making investigations. The Commission began by taking about 50 samples of water from the bay at various points between the Battery, and Coney Island on the one hand and the Battery and Raritan bay on the other, and analyzing them for numbers of bacteria, for colon bacilli, and for chemical evidence of sewage. These samples were all collected from near the surface of the water. The water for analysis was usually collected from a boat directly into sterilized bottles by a person trained in such work. After the bottles were filled they were immediately taken to the laboratory, and were examined, as a rule, within two hours of the time when they were collected. In addition to these examinations of water, specimens of oysters and clams were collected from various points and an- alyzed for the colon bacillus by the presumptive test. There were 51 specimens of shellfish analyzed. * Report of the New York Bav Pollution Commission to Hoi:. Frank Wayland Higgins, Governor of the State of New York, March 31, 1905. Printed by Brandow Printing Company, State Printers, Albany, N. Y., 1905. lO A. Bacterial Results - ^ I. BACTERIA IN THE WATER Most of the samples of water sent to the laboratory were examined to determine the numbers of bacteria which they con- tained. The medium used for this bacterial work was stand- ard nutrient gelatin. The bacteria were cultivated at room temperature and counted after 48 hours. In interpreting the results of the analyses for colon bacilli, presumptive evidence of the presence of coli in each of three fermentation tubes containing .1 c.c, i c.c. and 10 c.c. of water respectively, was taken to indicate pollution; none with .1, but a positive result with i and 10, was taken to mean probable evidence of pollution; none with .1 or i, but a posi- tive result with 10 c.c. was not regarded as sufficiently sig- nificant to warrant a conclusion. (a) First Series of Samples. — The first series of samples was collected on June 11, 1904, between 10 and 11 in the morning and between 4 and 5 in the afternoon. The morning samples Avere taken on an ebb tide and the afternoon samples on a flood tide. The numbers of bacteria found in this first series of an- alyses were large, considering the fact that the samples were all collected in the main channels of the harbor and not near any sewer outlet. There were from 2,000 to about 45,000 bacteria in each cubic centimeter of the water. There was no way to tell how many bacteria would have been present had no sewage been flowing into the harbor; but had the harbor been entirely free from sewage it seemed likely that the numbers would have been much smaller. The numbers of bacteria in clean sea water are hundreds, or less, and not tens of thousands per cubic centimeter. The num- bers in uncontaminated river water are, if not equally small, not usually so large as were here found, unless sewage is pres- ent. On the other hand, the bacteria in sewage are to be num- bered by the million. The inference seemed fair, therefore, that the bacteria in the harbor water might be taken as indi- cating the effects of sewage. II The numbers diminished with some regularity from the Battery to Coney Island, excepting in some samples taken in Gravesend bay, where local sources of pollution apparently existed. The tests for coli were of less interest, but seemed to in- dicate a better condition of the water at the Narrows and at Sea Gate than occurred in the Upper bay. On the w^ioule, the w^ater of the incoming tide was better than the water of the outgoing tide. (b) Second Scries of Samples. — Further analyses weie made in October with the object of learning something of the quality of the water along the Staten Island and Long Island shores, and, particularly, over the oyster beds which are sit- uated along the west side of the Lowxr bay. The samples were collected from the ends of piers ana docks between St. George and South Beach, Staten Island^ October 17, 1904, between 12:25 and 3:40 p. m. At the be- ginning of the sampling the tide was near the end of its flood ; at the end the ebb current had begun to flow. The results of these examinations, when interpreted AVith other information, were thought to afford an instructive illus- tration of several matters which were of much importance in this investigation. For example, the north side of Staten Island, from the Narrows to St. George, is provided with sewerage systems which discharge the sewage of 20,000 people or more into the waters of the Upper bay along this shore. When the samples of water were taken in this vicinity the current was running from east to west along this shore, carrying an increasing load of sewage with it. This is shown by the analyses, which indicate a contaminated condition of w^ater at St. George and a progressive reduction in impurity from this point eastward to the vicinity of the Narrows. The numbers of bacteria in this series ranged from 5,000 to 26,000 per cubic centimeter. (c) Third Series of Samples. — To investigate the quality of the water of Gravesend bay, samples were collected there on October 20, 1904. The samples were taken from a boat 13 which passed near the shore between i :45 and 3 :45*'l>:* m. The tide was rising. The results of these analyses were taken to indicate'lhat^. the water along practically the whole of the shore of Graves- end bay was contaminated by sewage. More than half the examinations for coli resulted positively even in samples of w^ater as small as .1 c.c. The numbers of " bacteria were smaller than might be expected, in view of the coli results, ranging between about 3,000 and 9,000 and occurring with considerable uniformity. The incoming tide which prevailed was distinctly favorable to purity in the samples. (d) Fourth Scries of Samples. — A final series of samples for bacterial analysis was taken along the east shore of Staten Island on October 22, 1904. This series extended down the Lower bay past the day-summer resorts of Midland Beach and South Beach and ran over the extensive oyster beds Avhich lie along this coast. The samples were taken between I p. m. and 5 140 p. m. The tide was rising. The results may be divided into three parts : ( i ) The samples which were collected between Rosebank and Midland Beach contained marked evidence of pollution; (2) the sam- ples from Elm Tree Beacon to beyond Great Kills contained but few bacteria and few of the colon type; (3) the samples collected from south of Great Kills to Tottenville contained considerable evidence of pollution. The numbers of bacteria ranged between wide limits in this series; that is, from about 900 to 60,000. The number seemed to depend upon the locality. The largest counts were always found in those parts of the harbor which received the most sewage. Two samples, averaging 13,000 bacteria to the c.c, were collected in Lemon creek, which drains about 2,000 acres of populated country. This creek was much used as a place for ^' drinking " ovsters. J3 2. BACTERIA IN SHELLFISH Most of tlie shellfish which are taken for market from the waters of Xew York bay are cultivated on the southeast shore of Staten Island, but some, and especially hard clams, are grown in tliat portion of the lower harbor known as Graves- end bay. To learn whether shellhsh grown in the bay bore evidence of pollution, specimens of oysters and clams were collected and examined by the presumptive test. The shellfish were collected directly from the ground where they were grown. At the laboratory they were ex- amined by opening the shells with a sterilized knife and mix- ing the contained liquid in portions of .i c.c, i c.c. and lo c.c. with fermentation broth and then proceeding as in w^ater analyses. The result showed that the shellfish which were grown in polluted water were generally polluted also. The samples did not always bear positive evidence of pollution. This is probably explained by the fact that some of the shellfish were cultivated in less polluted parts of the harbor than others. The oyster beds on the Staten Island shore seemed to lie between two great sources of danger : one the polluted water of the Upper bay and the other the contaminated water at the mouth of the Raritan river and Arthur Kill. The oysters which contained the fewest bacteria came from the vicinity of the Great Kills and Swash cliannel — points which are well removed from sewer outfalls and apparently beyond the most imminent danger from the sewage of the cities. The oysters which w-ere " drinked " in Lemon creek showed distinct evidence of contamination. B. Chemical Results The chemical analyses, especially the samples from the Upper bay, showed evidence of sewage in the water at all stages of the tide. The examinations did not warrant the opinion that the water was everywhere and at all times badly contaminated; but the chemical evidence well supported the bacterial results in showing that traces of sewage could be 14 found after the sewage had had what seemed a thorough mix- ing with the waters of the bay and after it had traveled miles from its points of outfall. One of the measures of pollution employed was the de- termination of nitrogen in the forms of free and albuminoid ammonia. The test for free ammonia was considered par- ticularly useful, for the reason that free ammonia is always present in sewage, and when found in large amount in water, is not likely to have been derived from a harmless source. By way of standards for comparison a table was prepared to show the amounts of free and albuminoid ammonia which exist in uncontaminated sea water, in drinking water and in sewage. These standards were kept in mind in considering the amount of free and albuminoid ammonia found in the waters of New York bay. There were 14 chemical analyses made. From these analyses it appeared that the water of the bay contained about 2j^ times as much free ammonia and about i J4 times as much albtiminoid ammonia as pure sea water, and about 6^ times as much free ammonia and about the same amount of albu- minoid ammonia as the Hudson river at Poughkeepsie. The most polluted samples were taken near the Battery, near Rob- bins Reef, at the Narrows and near Coney Island. Data collected in connection with studies for a new water supply for New York showed that the water of New York bay contained nearly six times as much free ammonia and about the same amount of albuminoid ammonia as the water of the Hudson between New York and Poughkeepsie. One of the surprising results of the investigation was the fact that the tide seemed to have little effect in eliminating the evidences of pollution. It had been supposed that the sewage which drained into the harbor was carried away by the water which flowed into the sea from Long Island Sound and from the Hudson river. But these analyses indicated that there was not a great deal of difference between the quality of the incoming and outgoing water. In some cases the currents flowing into the bay were more polluted than those passing out. It seemed likely that, in spite of the great tidal movement, the diluted sewage passed back and forth indefinitely in the bay and rivers, in the neighborhood of the sewers from which it came. The movement of the tides seemed to diffuse and distribute the impurities rather than to remove them permanently. The completeness of the diffusion of the sewage in the waters of the bay was considered to have such an important bearing on the question as to what ulti- mately becomes of the sewage, that it seemed desirable to col- lect data to show the proportion of sea water and river water in the bay under different circumstances, in order to learn, if possible, to what extent the water of the bay was regularl}^ flushed out. Henceforward studies of salinity occupied a prominent place in the investigations of New York harbor waters. C. Studies of Salinity The ccmmingling of sea water and land water was shown by analyses of samples of water taken near the surface at various points in and about the harbor. The substance which was taken as characteristic of sea water was common salt, or, as w^ater analysts term it, chlorine. For purposes of compari- son the w^ater of the ocean beyond the range of land water influence was taken as averaging 18,000 parts of chlorine to 1,00.0,000 parts of water, although the amount varies consid- erably in different parts of the sea. The water of Long- Island Sound was assumed to contain about 14,000, and the water of the Hudson at Poughkeepsie about 1.5 parts, per million. The results of about 80 analyses, made either by the Pollution Commission or by others, w^ere assembled to shov/ the different amounts of chlorine found at different points and under different circumstances of wind and tide. From these studies it seemed evident that the water of New York bay was not composed of land water and sea w^ater in any fixed proportion. It changes with the season. In the Lower bay it was found to range from about 20 fo to 100% sea water, according to location. A fair average for the Lower bay under ordinary conditions of weather, and beyond the range of local dilution, seemed to be about 75%. i6 The water of the Narrows was found to vary from about 43% to yj^/c sea wrater, the majority of samples averaging about 65%. At the Battery the samples ranged from 15% to 69% sea water, with an average in this vicinity, under what appeared to be fairly normal conditions, of about 45%. The lower Hudson was the scene of wide variations • in the proportion of salt. The Hudson at Spuyten Duyvil ranged from an hourly average of 0.5% to 44^ sea water for a whole day. . There was as much sea water on some occa- sions in the Hudson at Croton point as there was at other times at the Battery, -^^^i iTiiles nearer the ocean. It w^as evi- dent that the upper limit of brackish water might occur any- Avhere between Yonkers and Poughkeepsie. The chief cause of these differences was plainly the rainfall, for this furnishes the land water which dilutes the water of the sea. In the spring of the year, when the discharge of land water by the Hudson is at its height, the salt water is forced to an unusual distance toward the ocean. In late summer, when the rainfall is slight, and in the winter, when many inland streams are frozen, the sea water creeps up the Hudson to a surprising distance. Between Yon- kers and West Point the salinity is continually fluctuating. Every tide affects it. And, as the wind affects the level of the water in the bay, every storm has an appreciable effect upon the proportions of the mixture. The flow of the currents through the Narrows, East river and Hudson river seemed to have little influence upon the salinity of the water, except at seasons when the Hudson was discharging unusually large quantities of land water; at such times the action of the tides produces a marked effect. THE INVESTIGATIONS OF 1906- The foregoing investigations were supplemented in 1905 by further studies by the New York Bay Pollution Com- mission. This additional work was largely of a chemical and * Renort of the New York Bay Pollution Commission to Hon. Frank Way^and Higeins Governor of the State of New York, April 30, 1906. Prnited by Brandow Printing' Company, State Printers, Albany, N. \. 17 bacteriological character. In addition to the analytical work, inspections were made of the shores of the harbor. These inspections w^ere made in a careful and systematic manner, and produced results of considerable value. The principal points of information sought in 1906 were: 1. Whether the w^aters of New York bay were uniform in quality at all depths, or, in other words, whether a perfect mixture of the sea w^ater, land w-ater and sewage occurred; 2. To what extent the waters of the East river, Harlem river and Hudson river bore evidence of sewage pollution; 3. Whether the supply of oxygen in the water was always sufficient for the inoffensive decomposition of the organic matters present. The methods of analysis and the ways of expressing the results were the same as had been employed during the pre- vious year. There were 115 chemical analyses and the same number of bacteriological examinations made by the New York Bay Pollution Commission in 1906. As a rule, each water sample was used for both chemical and bacteriological analysis. For convenience in interpreting the data the results of the different examinations were considered separately. A. Bacterial Results L NUMBERS OF BACTERIA AT DIFFERENT DEPTHS Samples of water were taken at different depths in Upper New York bay to determine whether there was an appreciable dift'erence in the bacteriological conditions at the surface and at dift'erent points between the surface and the bottom. The first series of samples was collected from a boat on January 28, 1906, during a rising and falling tide; a second series was collected in the same way two days later, tow^ard the end of a flood tide and closely following the beginning of an ebb tide. The samples were taken at depths of from 5 feet to 80 feet below the surface. The results show^ed that there were more bacteria near the surface than in the water below^ The reduction in nam- i8 bers with depth was striking. It suggested the possibiHty that sewage and other decomposable refuse with which the bacteria were associated were not mixing uniformly with the water. Tests for B. coli seemed to confirm the conclusions which were derived from a study of the numbers of bacteria^ Up to this point the presumptive tests for coli had resulted positively in a large majority of all the samples examined in the commission's investigations; now, however, man}- re- sulted negatively at depths of 60 feet and over. (a) Lower Bay and Narrows. — The condition of the waters of the Low^er bay and Narrows was examined on Feb- ruary 17, 1906, by means of a series of samples collected from a boat. These analyses showed that there were several times as many bacteria near the surface as in the water near the bottom. The numbers of bacteria were not quite so large in the Lower bay as in the Upper bay, . but this difference was slight. Not so many samples of deep water as surface water gave positive results in the coli tests. (b) Upper Bay and Lozuer Parts of the East and Hudson Rivers. — A series of samples of water was collected in the Upper bay and lower end of the East and Hudson rivers on March 2 during rising and falling tides. The numbers of bacteria found in these tests were com- paratively large, and, in some cases/ decidedly so. The great- est numbers were in samples taken within range of extensive local sources of pollution. One of these sources of pollution was Gowanus canal; another was the large sewer which empties from the Brooklyn shore at Sixty-fourth street. The East river contained more bacteria than the Hudson river or the Upper bay, or the water off the Staten Island shore, which last was one of the most polluted localities investi- gated. Samples of water were taken from Bodine creek and from the Rah way river, in both of which streams oysters were ex- tensively " drinked " in preparation for the New York mar- ket. Both streams were believed, from previous investiga- tions, to be polluted with sewage. The conditions surround- 19 ing Bodine creek were described in the first report of the New York Bay Pollution Commission. The Rahway river re- ceived the sewage of the municipality of Cranford and the sewage of the city of Rahway only a short distance from the ix)int where the samples were collected. In view of the drain- age which entered these two streams, the numbers of bacteria seemed small. On the other hand, a large proportion of posi- tive results were obtained in the tests for B.- coli; in fact, nearly every examination resulted positively. (c) Rivers Surrounding Manhattan Island. — A series of analyses was made to determine the bacterial condition of the Hudson, East and Harlem rivers on April i, 1906. A flood current was running during the time the samples were being' taken. Nearly all the samples recorded in this series gave posi- tive results in the presumptive test for B. coli; the only ex- ception was in water taken from the Harlem river. The con- dition of the Harlem appears to have been much better than either that of the East or the Hudson river, although the numbers of bacteria were in no case small, considering the season of year when the samples were collected. The East river was more polluted than the Hudson or Harlem; the bacteria w^ere more than twice as numerous in the East river than in either of the other two rivers. The water near the bottom of the East river near the Bat- tery contained about as many bacteria as the water at the surface at this point. The Hudson, from its junction with the Harlem to Fortieth street, was decidedly polluted, accord- ing to these analyses. 2. BACTERIAL CONDITION OF SMALL ARMS OF THE HARBOR (a) Gozmnus Canal. — As was well known, the Gowanus canal on the Brooklyn shore was one of the most polluted arms of New York bay. The odors from this canal consti- tuted a decided nuisance, and the city of New York w^as con- structing pumping engines and a tunnel in order to flush out the waters. 20: In order to obtain an idea of the data which analyses of this water would yield, chemical and bacteriological exam- inations were made on February 3, 1906, of three samples of canal water taken from different points between the outlet and the head of the canal. There was a decided difference in the condition of the water at the different points. The bacteria were very numer- ous, and the amounts of free and albuminoid ammonia present were large. The tests for coli resulted positively in e\'ery case. (b) Lozver Bronx River. — Notwithstanding the fact that efforts were being made to protect the lower part of the Bronx river against sewage pollution, the condition of that stream was far from satisfactory, as shown by samples taken by the commission from different points between the dam and the mouth of the Bronx river on March 31, 1906, near high tide. The numbers of bacteria found indicated diminishing pol- lution as the river approached its mouth. This reduction was decided. All the tests for B. coli gave positive results. B. Chemical Results I. CHEMICAL CONDITIONS AT DIFFERENT DEPTHS (a) Upper Nezv York Bay. — Samples of water from dif- ferent depths at points between the Battery and the Narrows were collected on January 28, 1906, and analyzed chemically. The tide was rising. A second series of samples was col- lected on January 30, during the last of the flood and first of the ebb tide. The results showed that reduction in the amount of albu- minoid and free ammonia occurred in the water as the depth from, the surface increased. In some cases this dift'erence was considerable in others it was not marked. Averaging all the results, it was evident that the water near the surface was more polluted than the water below. 21 It is interesting to observe that the chlorine invariably increased with the depth, showing that there was a larger percentage of sea water at the bottom than at the surface of the bay. (b) Lozccr Bay and Narrozvs. — Samples of water were collected at different depths in the Lower bay and Narrows on February ly, 1906, near the time of high water. The re- sults showed that the chemical evidence of pollution did not vary inversely as the depth on this occasion. There was more free and albuminoid ammonia near the surface and at the bot- tom than between these points. These differences were marked. The data seemed to indicate that strata of water containing more sewage than occurred in the waters of the Upper bay lay at the top and bottom, while the water between was less contaminated. (c) Upper Nczu York Bay and Lozccr Parts of flic East and Hudson Rizvrs. — Samples of water were taken at dif- ferent points in the vicinity of the Upper bay on ]March 2, 1906, during flood and ebb current, and analyzed, with the re- sult that more sewage was found in the water than had been observed previously. Some of the samples, although not col- lected near visible sources of pollution, contained large amounts of free ammonia. The water at the lower end of the East river was especially remarkable in this resinect. (d) Rii'crs Surrounding Manhattan Island. — Samples of water taken from the East river, Harlem river and Hudson river were collected on April i, 1906, during a flood current. The water in the East river contained on an average more free and albuminoid ammonia than the waters of the Hudson or Harlem rivers. There was but little difference between the water at the surface and at the bottom, so far as the ammonia indicated. The condition of the Harlem river as indicated by these analyses was not far different from that of the Hudson. The determinations of chlorine showed that the Hudson river was comparatively free from sea water as far south as the middle of ^Manhattan Island, except at the bottom. There 22 was much more sea water at the bottom than at the top. A sample cohected near the bottom off Grant's Tomb, at One Hundred and Twenty-fifth street, contained about 13 times as much chlorine as the average of the surface samples above Fortieth street. Off the Battery there was nearly twice as much sea water at the bottom as at the top. There w^as a steady decrease in the amount of sea water in the Harlem river from the East river to the Hudson. 2. AMOUNT OF OXYGEN IN THE WATERS OF NEW YORK BAY AND VICINITY Inasmuch as the inoffensive digestion of sewage by tidal waters depends largely upon the supply of atmospheric oxygen, a series of analyses was made to determine whether there was as much oxygen present as necessary. The samples were collected, as already described, from, a boat on January 28, January 30, February 17, March 2 and April i, 1906. The analyses showed a good supply of oxygen in the water of the Upper bay at all depths. Under these circumstances offensive odors would not be formed unless the quantity of sewage discharged into the harbor was greatly increased. In many cases the amount of oxygen increased with the depth. Samples of water taken near the surface usually did not contain as much oxygen as did samples from below. This was contrary to what was expected and was taken to indicate that the disproportionately large numbers of bacteria Avhich existed near the surface consumed enough oxygen to reduce the amount. With reference to the water near the surface in the Upper bay and waters surrounding Manhattan Island, it was found that the oxygen was exhausted in only one of the samples examined. This sample was collected from Gowanus canal. The oxygen was below the average in the water of the bay opposite the outlet of the Gowanus canal and near the outfall of the trunk sewer at Sixty-fifth street, Brooklyn. These de- ficiencies indicated the effect of the sewage upon the harbor waters. There was no deficiency of oxygen in any of the samples collected in the Hudson and East rivers. A difference between the oxygen present at the bottom and near the sur- face of the water was noticeable in the Hudson river off Grant's Tomb. Here there was more oxygen at the surface than at the bottom, indicating a purer condition of water at the top. C. Results of Sanitary Inspections Along the Shores OF New York Bay Inspections along the shores of New^ York bay were under- taken in the latter part of March and continued until the middle of April, 1906. The inspector w^alked along the shores and made note of sewage and other refuse where it could be seen either on the shore or in the water. An attempt was made to make these inspections more than ordinarily definite and exact. Careful note was taken of the wind and tide, and recorded with the date, hour and place where the conditions were observed. The conditions were described in such a way as to indicate not only the location and character of the polluting matter found, but, as far as practicable, its quan- tity. For example, the number of cubic yards of vegetable and animal refuse on a measured area of beach was recorded wherever practicable. (a) Upper Bay. — It was found that the eastern shore of Staten Island accumulated considerable quantities of refuse, which was carried to it by the tide. Some portions of this shore above the Narrows were decidedly foul with sewage, and it was observed that much of this sewage was being dis- charged by the sewers of Staten Island itself. The New Jersey shore of Upper New York bay was, on the whole, com- paratively free from visible traces of sewage, except in the neighborhood of the outfalls of local sewxrs. The eastern, or Brooklyn, shore of Upper New York bay was, for nearly its whole length, obviously polluted with sewage, refuse and garbage. The amount of this pollution diminished in the direction of the Narrows. 24 Tl'ie shores of the islands in Upper New York bay were^ for the most part, comparatively clean, except for sewage which was discharged from buildings on the islands them- selves. There were points, however, along Governor's Island and Liberty Island where remains of sewage were found which could not have originated from local drains, for none existed close by. (b) Lozvcr Bay. — Both shores of the Lower bay were polluted with sewage refuse to some extent for a considerable distance from the Narrows. The Staten Island shore con- tained large quantities of garbage as far as the inspections were continued in a southwesterly direction; that is, to Mid- land Beach. The north shore of the Lower bay was fairly free from visible evidences of sewage, except near the outlets of local sewers, where small amounts of sewage scum were occasionally seen floating to a distance from the shore. The presence of large grease balls, which could only have been de- rived from sewers of considerable length, showed that some sewage was evidently transported to these shores from the Upper bay. That portion of the shore of the outer harbor which is in the vicinity of Norton's point contained so much driftwood, garbage and sewage matter of various kinds that it seemed reasonable to suppose that this point was a collecting centre for refuse which was carried out of the Upper bay by the tidal currents on their way to sea. As much as 5 cubic yards of animal and vegetable refuse were found on 400 square feet of beach in this vicinity. Men gathering wood said that the supply of fuel was inexhaustible. From Norton's point eastward there was a constantly diminishing amount of putrescent refuse, until at about mid- way between the two ends of Coney Island it was reduced to an occasional lot of garbage or a dead -animal. The shores and water of Sheepshead bay wxre fairly clean, as might be expected at that season of year. (c) Oyster Grounds. — The inspections confirmed what the commission's chemical and bacteriolog^ical analvses had already shown concerning the objectionable practice of im- mersing oysters in the creeks in the immediate vicinity of New York City. Bodine creek on Staten Island, where large quantities of oysters were " drinked " in preparation for mar- ket, was reported by the inspector to be obviously polluted by sewage. The shores w'ere strewn with vegetable and animal matters, and a scum of grease and petroleum was on the water. Equally objectionable conditions connected with the oyster industry were found elsewhere. The liquid part of the sewage of the towai of Sheepshead Bay was found to be emptied, after being treated with chemicals, into Bull's creek in the imme- diate proximity of oyster beds. The danger of polluting oysters in the ways here indi- cated W'as clearly pointed out in the first report of the New York Bay Pollution Commission. The existence of the re- stilting danger to the public health was emphasized by a typhoid fever outbreak which occurred at Lawrence, N. Y".. in 1904, and was ascribable to oysters and clams grown and cultivated within the New Y'ork Citv limits. D. Summary of Conclusions Reached by the New Y^ORK Bay Pollution Commission The principal opinions which the New Y^ork Bay Pollu- tion Commission formed from its investigations are scattered through the various divisions of the two reports which the commission made. The commission found that the waters of the bay and adjacent waters were unmistakably, but not as yet badly, polluted. It was clear that the sew^age was not uni- formly dispersed and diffused through the breadth and depth of the tidal currents, but that the sewage polluted the water more at the surface than in the depths below. The discharge of sewage along the shores often led to decided local nuisances. Offensive matters from the sewage were sometimes trans- ported long distances by the tides and winds and deposited on shores remote from any sewer outlet. Excepting in such heavily polluted waters as Gowanus canal, there was probably always enough ox3^gen in the waters about New Y^ork to 26 enable the agencies of decomposition to carry on their work of digesting the sewage without danger of producing offensive odors. Although the existing method of disposing of the sewage of New York was apparently as suitable as any method of emptying the crude sewage of the metropolis into these waters could be, it was far from being always satisfactory. The disposal of sewage at the pierhead line, as practiced on Manhattan Island, was to be preferred to the plan of empty- ing it at the bulkhead line, as was generally practiced else- where in this vicinity. No other method of disposing of the sewage of New York and vicinity was suggested as the result of these investigations. It was evident that some other method should be devised, but the commission reported that a satisfactory study of this ques- tion would involve investigations of a far more exhaustive character and wider scope than had thus far been possible. The following extract from the final (1906) report gives the opinion of the New York Bay Pollution Commission with respect to the need of extending the analytical work upon broader and more adequate lines : '' The total number of analyses was very small, con- sidering the size of the problem to be studied. The great extent of the harbor and its tributaries, and the multiplicity of the conditions of pollution and purifica- tion which called for investigation needed far more ex- tensive analytical study than the slender means of this commission permitted. The analytical work done thus far should be regarded only as an indication of the great value and meaning which would attach to similar work if carried out on a large scale. It is hoped, if further studies are to be made of the conditions of these waters, that opportunities will be afforded for keeping the harbor and adjacent w^aters under ade- quate observation for, at least, one full year. Facilities should be provided for the collection and analyses of several thousand samples." 27 Section II. Investigations Made by the Metropolitan Sewerage Commission in 1907 It was recommended by the New York Bay Pollution Commission that the investigations necessary to an under- standing of the condition of New York harbor should be made by a board of official investigators and that the new board be given jurisdiction and sufficient resources to enable it to make a comprehensive study of the whole question of harbor pollution, including remedial measures. The task of making this study was placed in the hands of a commission appointed for the purpose in 1906 by the Mayor of the City of New York. The act providing for the com- mission was chapter 639 Laws of 1906 (amended by chapter 422, Laws of 1908). The official title of the commission was the Metropolitan Sewerage Commission of New York. Data were at once collected relative to the chemical and bacteriological condition of the harbor and neighboring waters. In connection w^ith those studies samples of mud and other solid matter were taken from the bottom of the harbor for analysis. In addition to these analytical studies, observa- tions were made of the tidal currents of the harbor by means of floats. The data collected by this commission were duly recorded and preserved, and, to some extent, tabulated; but little study of the deductions derivable from the' data was made until after the commission was re-constituted in January, 1908. Under these circumstances a complete digestion of the data has been impracticable, and much useful information has doubtless escaped discovery. Care has been taken, however, to examine the records for such light as they are capable of throwing upon the questions which the reconstituted com- mission considers to be of principal importance. 28 A. Numbers of Bacteria in the Water The determination of the numbers of bacteria in the water was the most interesting and profitable kind of analysis which was made. The total number of samples of water analyzed bacteriologically was 755. These samples were taken at 188 places. All were collected in the nine months between Jan- uary 22i and October 18, 1907. The samples were collected in many localities, sometimes under circumstances which indicated that particularly useful data should result therefrom. For example : Several series of samples were taken in the neighborhood of large sewer outfalls, across the rivers and channels, in the polluted Go- wanus canal and Newtown creek and in the little-studied , Newark bay. Iw some of these series the samples were collected along a line parallel with the direction of the channel, and in others at a single point through a considerable period of time. The water was collected at various depths, ranging from near the surface to 100 feet below. In addition to the quantitative work, the samples were analyzed in some cases for colon bacilli by the so-called pre- sumptive test. This qualitative work is referred to elsewhere. I. SURFACE SAMPLES The samples which are recorded as having been collected from the surface of the water were generally taken at a depth of a few inches below the actual surface. In only one case was a sample taken at the surface itself. The bacteria were undoubtedly more numerous at the actual surface where these samples were taken, but, inasmuch as many of the bacteria found of any water surface are likely to have been derived from the air, the custom, common in water analyses, of taking the sample from a little below the surface was adhered to. Considering all the results which are capable of being brought together to form a fair average, it appears that the number of bacteria in the main channels ranged from about 1,000 to 10,000. Numbers from 10,000 to 100,000 represent 29 comparatively heavy pollution; numbers from 100,000 to 1,000,000 and over occurred wherever heavy pollution existed. The bacteria were more numerous in places near sewer outfalls than elsewhere. For example, the numbers rose to 808,000 near the South Brooklyn shore, 625,000 at the head of Gowanus canal, 25,500 in Wallabout bay, 106,000 in New- town creek, and 69,000 in Newark bay. The smallest number of bacteria found in any sample was 150. This occurred in the Hudson river off Spuyten Duyvil — ■ one of the cleanest localities investigated. The place where the greatest number of bacteria occurred in the main channels, Avas immediately west of the Brooklyn anchorage grounds and just south of Governor's Island. Analyses made from samples collected at a greater number of points might have shown different minimum and maximum numbers than those just given, but this is not important. The numbers of bacteria Avere smaller the farther the sam- ples were collected up the Hudson. The same is true of samples taken up the Harlem going from the East river toward Spuyten Duyvil. The numbers in the harbor diminished from the Battery toward the open sea. But the numbers increased toward the upper end of Newark bay and the Gowanus canal. The larg- est count in the polluted Newtown creek w^as found about half- way up from the mouth and not where the greatest amount of polluting matter entered the creek. Apparently some of the hquid trade wastes which are emptied into the creek have a destructive action upon bacteria or the bacteria multiply in the water. Considering the results as a whole, the numbers of bacteria in the harbor waters seem to give a fairly accurrate idea of the intensit}^ of sewage pollution. Speaking generally, it can be said that counts ranging as high as 1,000 represent con- ditions which need no immediate remedy. Numbers between 10,000 and 100,000 mean nearby or heavy pollution; and arc sometimes found where the water is so contaminated as to be discolored and of unpleasant odor. Numbers ranging from 30 100,000 to 1,000,000, and above, generally represent offensive conditions. (a) Seasonal Variations. — The analyses of samples of water collected from a single locality at different seasons of year and at similar stages of tide, indicated that larger num- bers of bacteria occurred in the winter, spring and fall than in the summer. This question is of such interest that further details of the data will be given. A series of six samples was. taken in Newtown creek on September 11, 1907, which, on analysis, gave an average num- ber of 5,500 bacteria per c.c. A series taken at the same point under the same tidal conditions, October 7 to 10, gave an average of 36,000. Again, at Hamilton avenue, on the Gowanus canal, the largest number of bacteria found in a series of samples collected during a flood tide on February 2y was 320,000. Under similar conditions 17,000 were found at this point on September i. The largest number during an ebb tide at the same place as the last was 97,000 on October i ; and there were 16,000 at this point on August 5. Two exam- inations were made at a point in Gowanus bay, one on October . I and the other August 5, 1907. The sample collected in August contained 13,000 and the sample in October 64,000. Finally, near the South Brooklyn shore, of the results of 17 analyses, classified by tides, the largest numbers occurred on October i, viz., 808,000, and the lowest June 11, 3,080, both on a flood tide. The maximum on an ebb tide 78,000, occurred on February 4; the minimum, 8,300, on August 5. It appears from these facts that the numbers of bacteria varied with the season and that the bacteria were more numerous in fall and winter than in summer. The results of the analyses of solid matter from the har- bor bottom, seem to indicate that the numbers of bacteria were also generally larger in cool weather than in warm. But some large numbers in June, and some comparatively small ones in March, make it unsafe to consider that there are greater num- bers of bacteria on the bottom in winter, as is true of the bac- teria in the water. 31 An explanation of the fact that larger numbers of bac- teria were found in winter than in summer is desirable, but, in the absence of information concerning- the nature of the conditions which make for the preservation or destruction of the bacteria, it is impossible to make an accurate statement. (b) Disappearance of Bacteria from the Water. — It is probable that the bacteria which are discharged with sewage do not find conditions in the harbor waters favorable to their existence, and expire rapidly. It is likely that the sewage bacteria do not, except under certain and probably abnormal and restricted conditions, multiply in the water, but perish after what must be considered a brief interval. It would seem, therefore, that the harbor is not like a cesspool in which bac- terial multiplication is a leading feature. Either the sewage in the harbor is disposed of in other ways than by bacterial action or the bacterial action is very rapid. The self-cleansing power of the harbor is a phenomenon of the greatest interest and importance, and it is desirable that it be understood. 2. Numbers at Different Depths When a series of water samples was taken at different depths it was found that the numbers of bacteria generally diminished from the surface downward. The count at 20 feet below the surface was often only one-half that at the sur- face. The rate of diminution with depth was not uniform, but varied considerably. It is true that in the Hudson off Spuyten Duyvil a single series of observations which was continued through two tides indicated the bacteria did not decrease, but increased, in num- bers with the depth at which the sample was taken. But this was probably due to circumstances which are peculiar to the Hudson. It seems probable that the fresher and purer water of the river at this point sometimes flows, without intimate admixture, over a denser substraturii of salt water brought by the tide from the lower reaches of the river, and that this substratum sometimes carries a load of sewage from the more polluted parts of the harbor. An increase in the number of bacteria with depth has never been found at the mouth of the Hudson river, even during a freshet, the surface pollution there being sufficiently heavy to make the bacteria at the top more numerous than at any point below. The number of bacteria found at the greatest depth at which samples were taken anywhere, viz., lOO feet, was in the Lower bay; the number was 300. This occurred at a time when there were 900 at the surface at the same point. The smallest count in the middle of the Narrows, the junction of the Upper and Lower bays, w^as 180, at a depth of 85 feet; at this time there were 1,600 bacteria at the surface at the same point. It is evident from the foregoing that, as a general thing, there are many more bacteria near the surface than in the depths of the water in the bay, a conclusion which was reached by the New York Bay Pollution Commiission and stated in its second published report. With respect to the difference in numbers of bacteria at different points across the channels from one shore to another, the typical condition is this : The fewest bacteria occur at the bottom near the center of the cross-section of the river or channel, and from this point they increase vertically and hori- zontally, the largest numbers being at the surface near each shore. The differences are often considerable. This seems reasonable, since the sewage and other drainage which enter the harbor are discharged at the surface and along the sides. ! 3. Diurnal Variations A dift'erence in the numbers of bacteria was observable be- tween samples collected during the day and night. A series of day-and-night observations made near Fifty-third street, Brooklyn, gave a maximum at 9:15 p. m., and a minimum at 6:00 a. m. These differences were apparently independent of the tides. They seem to have been due to the fact that less sewage is discharged into the harbor at night than in the day time. If this series of observations correctly represents the conditions which generally occur throughout the harbor at 33 different hours, it indicates that the bacterial effects of dis- charging sewage into the harbor are not of a lasting character — a probability which has already been pointed out on the basis of other evidence. The polluting effect produced by heavily contaminated creeks and other tributaries upon the general waters of the harbor was made apparent by collecting a series of hourly sam- ples through a period of eight hours in the East river near the mouth of Newtown creek. As might be expected, the numbers of bacteria were largest when the tide favored the discharge of the creek water into the river. 4. RELATION TO STAGE OF TIDE The relation of tide to the numbers of bacteria depended upon the location of the point under observation with refer- ence to the sources of pollution. During flood tide there were fewer bacteria in the water than during ebb tide in the Upper and Lower bays, Kill van KuU, Newark bay, lower Hudson and lower East rivers. In general it may be said that there were fewer bacteria in the harbor water when the tidal cur- rents were flowing toward the land than when they were flowing toward the sea. But there were exceptions to this rule. In the upper East river and Harlem river the water at ebb tide contained fewer bacteria than the water at flood tide. The reason there w^ere generally fewer bacteria when the water was flowing in from the sea than when it was flow- ing outward is not made clear by the data, but it is not im- probable that it was due to a numbef of causes. It is known that sea water in large amount enters the harbor with each tide, and the water which comes in is undoubtedly cleaner than the water which goes out. It is cleaner for the reason that it is mixed with some pure sea water, and, perhaps more important still, the dirty water has partly purified itself. 34 B. Numbers of Bacteria in Solid Matter at the Bottom of the Harbor There were 705 samples of solid matter collected from the bottom of the harbor and analyzed to determine the numbers of bacteria present. These samples were from 371 localities. The samples were chiefly taken from the surface of the mud, but in y-^ cases analyses were made of material taken at dif- ferent depths below the surface of the harbor bottom. The samples were collected from a large number of local- ities, including the Hudson as far north as Yonkers ; Newark bay, which lies to the west of Upper New York bay ; and Am- brose channel, near the ocean. The samples were all taken between February 14 and October 2, 1907. Some samples were taken close to the shores, others at points in the channels at places known to be polluted, and still others in the grossly contaminated Gowanus canal and Newtown creek. Pains were taken to collect the material in ways to insure freedom from admixture with the water through which the sampling apparatus was lowered and raised, but how success- ful these efforts were is not revealed by the data. Two special pieces of apparatus were made for the purpose of getting* specimens without contamination, and were used to collect the samples where the latter were taken from different depths below the surface of the harbor bottom. In the following statements the numbers of bacteria are given as having been contained in one gram of material dried at a temperature of about 100 degrees centigrade. If we assume that this material contained as much water as solid matter, a supposition apparently close to the truth, the num- ber of bacteria per gram of wet solid can be ascertained by dividing the numbers given by two. 35 I. NUMBERS AT THE SURFACE OF THE BOTTOM (a) Maximuni and Minimum Numbers. — The largest number of bacteria found in any sample of solid matter from the bottom of the harbor was 26,000,000; this was in Go- wanus bay. The smallest count was 7,500, which number occurred at two points : one in Ambrose channel and the other off Hoffman Island. It is to be noted that both of these points were in the lower bay and far removed from any immediate source of pollution by sewage. Nevertheless, they were well within the limits of the outer harbor and in the direct line of the main current from Upper New York bay. The smallest count below the bottom was 4,000. This was found in a sample collected off Constable point at a depth of 12 feet 8 inches below the surface of the bottom. The very fewest bacteria found in any sample was 2,800. This sample was collected from a Government dredging scow which happened to be working in Ambrose channel. The possibility that this sample came from below the normal sur- face of the bottom and the chance that the material was acci- dentally mixed with sea water, must be taken into account in considering the result. It is an important result in so far as it shows that the bacteria were not excessively numerous at this point. (b) Variation in Numbers. — Samples of material from the bottom taken at adjacent points sometimes gave different results. The greatest difference between two samples col- lected close together occurred in Gowanus bay, where one sample gave 400,000 bacteria and another 19,000,000. There is no explanation in the reports of analysts to account for this dift'erence. The smaller count was in a sample collected on an ebb tide and the larger in one collected on a flood tide, but it is not probable that the stage of the tide had an appreci- able effect upon the numbers. (c) Numbers in Water and Solid Matter Compared. — Considering the results of these analyses as a whole, it is evi- dent that the numbers of bacteria at the surface of the harbor 36 bottom were far greater for a given weight of sample than for water, even surface water. If the sohd matter when dry weighed about half as much as it did when w^et, the bacteria on the surface of the bottom probably were from about 15 to 250 times as numerous as in the water at the surface at the same spot, or at least 400 times as numerous as in the water near the bottom. The reasons for these large numbers of bacteria in the solid matter at the bottom are not discoverable from the data brought out in the analyses. This solid matter was not proved by other facts to be due to deposits of sewage. It is interesting to note that the samples often contained a large amount of organic matter which was either putrefying or ready to putrefy as soon as it was kept at a favorable tem- perature. Nearly all the samples, when they were put into bottles, corked and kept in the laboratory for a few days, evolved gas. This gas was offensive and apparently con- tained sulphuretted hydrogen. The solid matter was mostly of a blackish color, except where the tidal currents were strong, in which case it consisted largely of clean sand. It seemed to make little difference how^ heavy was the pol- lution of the water; if the currents were strong the bottom was clean. Where the water was comparatively quiet, of- fensive black mud was likely to be found. An extensive area of this mud lay south of Governor's Island and another covered that part of the harbor known as the Jersey Flats. (d) Localities Having Large Numbers. — Comparing one section of the harbor with another, the bacteria in the material at the bottom were numerous in the Upper bay and in that section of the harbor immediately west of the Brooklyn shore. The numbers were large, also, on the northern half of the New Jersey Flats in the Upper bay, but small on the southern half of these flats. The numbers were always large in the vicinity of sewers, large in Gowanus canal, in Wallabout ba}' and canal, and in Newtown creek. 37 2. NUMBERS BELOW THE SURFACE OF THE BOTTOM The samples collected beneath the surface of the bottom of the harbor in the y^i cases in which such samples were taken were gathered and analyzed between February 14 and March 22, 1907. Tlie localities from which the samples were collected were the Gowanus canal ; the west side of the Upper bay ; near the Brooklyn shore; near the Staten Island shore, and the Harlem river. The greatest depth from which a sample was collected was 13 feet 8 inches below the surface of the bottom.. (a) Diininution with Depth. — The data show that the bacteria, as a rule, diminished in numbers with the depth ar which the material was collected, although some marked ex- ceptions to this rule occurred. One of these exceptions has a definite explanation, but the causes of the others are not evi- dent. The exception occurred off Kingsbridge on the Harlem, ship canal. Here nearly three times as many bacteria were found at a depth of 2 feet as at the surface of the bottom. A note made by the analyst who collected the sample states that a deposit of peat was found here. On examining the result of other analytical studies of this sample, it is apparent that the large number of bacteria were due to the peat. The number of bacteria generally decreased as the depth into the bottom increased, but the rate of this change was not uniform. Thus, one sample collected at 13 feet 8 inches below the surface of the mud contained only about 6 per cent, of the number found at the surface, while another sample at 13 feet 2 inches contained more than half as man}^ bacteria as were found at the surface of the mud at the same point and time. It is impossible to derive from the data any genera] statement by which the diminution of bacteria with the depth below the surface of the harbor bottom can be described. The depth of water over the bottom has not been shown to have any effect on the number of bacteria at the surface of the bottom or beneath the surface at any depth. 38 Inasmuch as considerable importance attaches to the num- bers of bacteria in the sohd matters at the bottom of the har- bor, it is of interest to state the results of some further ex- aminations of the data, although these examinations seem to justify no immediately useful conclusions. The number of bacteria decreased with the depth at which the sample was taken below the surface of the bottom, or was about the same, in 60 per cent, of all cases. The number in- creased with the depth in 40 per cent, of all cases. In those Instances in which an increase was noted with the depth, the average excess of the largest number over the surface count was 142 per cent. The largest increase with depth was about 700 per cent. ; this happened near Bayonne. The largest de- crease with depth was from 74,000 to 5,000, a difference of about 15 times the smaller number; this occurred near Con- stable point. (b) Variation zuitJi Locality. — The samples taken in the Harlem river indicate that the number of bacteria were much smaller west of Kingsbridge than elsewhere. The greatest numbers were between One Hundred and Fifty-second street and Randall's Island. Here the pollution of the river by sewage is probably greatest; one of the largest sewers which discharge into the Harlem empties ai One Hundred and Fifty- first street. The series of samples of solid matter collected from the bottom across the Upper bay from a point west of Ellis Island to Constable point, contained a marked excess in numbers of bacteria at all depths below the surface of the bottom near the point known as Black Tom, on the Jersey shore. In another series collected between Communipaw^ and Lib- erty Island maximum numbers occurred near the shore at the north end of this line, off Ellis Island and near Liberty Island. In the foregoing series it should be remarked that several samples were collected which showed greater numbers below the surface than at the surface of the harbor bottom. (c) Usefulness of these Data. — The examination of ma- terial from the harbor bottom did not yield results comparable 39 in definiteness and utility with the resuUs of numerical analyses of bacteria in the water samples, yet they are of con- siderable value when considered with other evidence. When the data were plotted in graphic form facts of much interest became evident. The whole work would have been of much greater value if samples of sea w^ater and of harbor water beyond the chance of contamination had been analyzed for comparison. In the absence of such controls it is impossible to state whether the numbers of bacteria in the harbor de- posits were or were not excessively high. C. Presumptive Test for the Colon Bacillus Analyses were made to obtain such information as coulfl readily be had concerning the presence of the colon bacillus. The method was the familiar presumptive test as modified by Jackson, in which the samples are inoculated into a liquid medium which is capable of undergoing fermentive changes through the action of colon bacteria. The presence and nature of the fermentation, as indicated by the amount and composition of the gas formed, was taken to indicate the presence of the bacillus. I. COLI IN THE WATER As is customary in this kind of analysis, the results were stated as positive or negative, according to whether or not the test indicated that the colon bacillus was present. The total number of colon determinations made with samples of water was 344. The samples were collected from about 120 places. (a) Prevalence of Coli. — In no case were all the results negative in samples collected at the surface. In only nine cases were negative results obtained with o.i c.c, and of these, six were in localities where other tests gave positi\-e results with o.i c.c, viz.: Newtown creek, off the South Brooklyn shore and the Hudson river at Spuyten Duyvil. From this it appears that the colon bacillus was present in 40 large numbers, as far as this test is capable of proving the presence of the colon bacillus, at all points above the Narrows and probabh^ in the Lower bay. The greatest depth at which the test was positive, both w^ith O.I c.c. and i c.c. of water, was 50 feet. This occurred near pier 10, East river, on the Manhattan side. One posi- tive result for i c.c. was found at 60 feet. No positive re- sults whatever were obtained at 100 feet. (b) Absence of Coll in Deep Water. — The circum- stances which caused this germ, so characteristic of sewage, to exist abundantly at the surface of the w^ater and not at the bottom are not entirely understood. Turning for explanation to other parts of the analytical data, it is found that the num- bers of bacteria of all kinds in the water were smaller in the depths than at the surface and that this difference was marked. 2. COLI IN THE SOLID MATTER AT THE HARBOR BOTTOM When samples of solid matter from the bottom of the harbor were anal3^zed for colon bacilli, these germs were usually found to be present. The number of these analyses was 322. The samples were collected from 243 places. (a) Coli at the Surface of the bottom. — Evidence of colon bacilli was absent in only seven samples of surface ma- terialj viz., three in the East river, one in Newtown creek and three in the Lower bay. These seven exceptions do not necessarily indicate that the bacilli were actually absent, for the sample used was very small and the method of analysis not infallible. Had duplicate samples been taken the results might have been different. Analyses for colon bacilli were made with 32 samples of solid matter from the bottom of the Lower bay. Li ten of these the evidence was positive with both i c.c. and o.i c.c. of water. In 19 cases the results were positive for i c.c. negative for o. i c.c. Li only the three cases just noted were the results negative for both i c.c. and o.i c.c. From the foregoing it seems safe to infer that the colon bacillus was present, so far as the presumptive test could 41 prove the existence of this hacillus. at the surface of the bot- tom of the harbor at all points in the Upper and Lower bays, including the rivers and canals. (b) Coli Below the Surface of the Bottom. — Twenty-five tests for the colon bacillus were made of material taken at different depths down to 6 feet below the surface of the bot- tom. At 6 feet all results were positive for tw'O locations, viz., the Harlem river at One Hundred and Thirty-third street and the East river at the foot of State street, Brooklyn. All results were positive for the bottom of the Hudson river off the piers of the Central Railroad of New Jersey. The Har- lem river material generally gave positive results with samples of I c.c. down to 6 feet below the surface of the bottom, but not always with samples as small as o.i c.c. The material in the Spuyten Duyvil creek gave a positive result only once, viz., at the surface with i c.c. ; no positive results were ob- tained with material collected from below the surface. From the foregoing it appears safe to infer that so far as the presumptive test can show, the colon bacillus exists very generally in the solid matter below the surface of the bottom in the main divisions of the harbor and in the more polluted tributaries. In some localities this bacillus appears to be present in large numbers to a considerable depth below the bottom. It so happens that the points where this organism was most prevalent are localities where a great deal of sewage is discharged. On the other hand, all parts of the harbor which receive heavy contributions of sewage did not yield colon bacilli, at least, not in such numbers as miHit be expected. D. Results of Chemical Analyses I. FREE AMMONIA IN THE W^^TER The number of samples of water analyzed for free ammonia was 47. Of these, two were taken near pier A, at the mouth of the Hudson river, and the rest near the shore of South Brooklvn. 42 The amount of free ammonia varied widely, the limits being 0.005 to 1.65 parts per million. The smaller of these two is recorded as found about 500 feet from the pier at Fifty-second street, Brooklyn, 10 feet below the surface of the water, on January 29, 1907.° The maximum was found between the piers at Forty-ninth street and Fifty- third streets, Brooklyn, on January 24, 1907. (a) Comparison zmth Other Results. — By way of com- parison it is to be noted that the maximum amount found by the New York Bay Pollution Commission was 0.210 near pier I, North river, and the minimum 0.052 near Sandy Hook light vessel. The minimum found at the surface in 1907 was 0.008 off Fifty-second street, Brooklyn, January 28. From the foregoing it is evident that the range in the amount of free ammonia found was not only much greater in the samples analyzed in 1907 than in those examined by the New York Bay Pollution Commission, but was remark- able, the minimum for its smallness and the maximum for its greatness. It is scarcely conceivable that there was really only one-tenth as much ammonia in the water off Fifty-second street as in the water of the open ocean. The average of 24 samples collected during the clay and night at different depths off Fifty-second street, Brooklyn, January 28, 1907, was o.oii, an exceedingly small amount. The average found at the surface was 0.013, or scarcely more than the general average just mentioned. These amounts of ammonia are so very small that they would not cause suspicion of pollution to be cast upon the sample if it had been drinking water. It is decidedly less than the figure found in any sample of water from New York bay or the Hudson as given in either of the two published re- ports of the Pollution Commission. There is no apparent ex- planation for these curious data, and the conclusion is irre- sistible that they were inaccurate. (b) Relation to Tide and Depth. — The amount of free ammonia found oft* pier A was 0.167 on the flood and 0.1628, or practically the same, on an ebb tide. This may be com- pared with 0.210 found by the Pollution Commission in 1904. 43 The free ammonia decreased as the depth increased when the initial amount was very high, as, for example, in three cases wdiere i.ooo part or more was found at the surface. The three examples referred to were : near Forty-ninth street, Brooklyn, at a depth of i foot, the free ammonia was 1.54; at 20 feet, 0.224. Again, at 2 feet, 1.65; at 10 feet, 0.396; at 20 feet, 0.158, Finally, at 2 feet, 1.005; at 10 feet, 0.355; ^^ 20 feet, 0.380. No such differences were noted in the second Pollution Commission report. When there was little ammonia at the surface there was often less at a slight depth and more again further down. Taking ten analyses representing three depths : at the surface, 10 feet and 20 feet below, the average amount of ammonia was 0.777, 0.061 and 0.666 respectively. An excess found at 20 feet over that at 10 feet occurred in nine out of ten cases. Assuming that the analyses were accurate, the simplest explanation of this singular reduction and increase is that the water was most polluted at the surface, as indeed from other evidence it is known to have been, and that the increase at 20 feet was due to an admixture with mud or other refuse stirred up from the bottom. No analyses were made of water collected from depths of more than 20 feet below the surface. (c) Diurnal Variations. — When samples were collected tlirough the day and night of January 28, it was found that the greatest amount of ammonia was present at noon and the least at 3 :oo a. m., using the data for all depths to give these averages. Considered as a whole, these determinations of free am- monia throw little new light upon the questions which needed study, and it seems so likely that they were inaccurate that it appears best to eliminate them from further consideration. 2. ALBUMINOID AMMONIA IN THE WATER The samples of water which were analyzed for free am- monia also were examined for albuminoid ammonia. As has been said, there were 47 samples and they were all collected either from the mouth of the Hudson or near the South Brook- lyn shore. 44 The albuminoid ammonia varied as did the free ammonia with respect to depth and time. (a) Minimum and Maxiniiun Results. — The minimum amount of albuminoid ammonia was less than found in any of the previous examinations recorded by the New York Bay Pollution Commission. The least amount was 0.014 parts per million on January 29, 1907, off Fifty-second street, Brooklyn, at depths of 10 and 20 feet. The least amount found near the surface was 0.016 on the same day at the same place. By w^ay of comparison it may be noted that the smallest amount of albuminoid ammonia recorded in the first published report of the Pollution Commission was o. 100 off pier I, North river, and in the second report 0.170 in the Har- lem river. The maximum amount of albuminoid ammonia was higher than that given in any previous report, viz., 1.94, off Fifty-ninth street, Brooklyn. The second report of the Pol- lution Commission gave, as a maximum, 1.430; this was found near the Sixty-fifth street sewer. South Brooklyn. The maximum amount of free ammonia recorded in the second report of the Pollution Commission was 7.000; this oc- curred in Gowanus canal, where in 1907 only 1.65 was found. (b) Signiiicancc of Results. — The results of analyses of albuminoid ammonia wdiich were made by the Metro- politan Commission or its predecessor, the New York Bay Pollution Commission, were too few and two restricted in locality to enable useful conclusions to be drawn from them. They seem to indicate, when taken w^ith the data for free ammonia, a general correspondence with the intensity of sewage pollution. It would be unfair, however, to assume that the exceptionally small amounts of ammonia found in some of the samples indicated exceptional freedom from sewage. Such a conclusion would be in opposition to all evi- dence collected from other quarters. Considering this matter as a whole, it probably is best to take no account of the deter- minations of ammonia made in 1907, since it is practically certain that thev were inaccurate. 45 3- CHLORINE IN THE WATER (a) Value of Results. — Taken separately, or in connec- tion with the resuhs of previous analyses of the New York Bay Polkition Commission, the chlorine analyses made for the Metropolitan Sewerage Commission constitute a fairly large mass of data, and throw important light upon the ad- mixture of sea water and river water in the harbor and its various tributaries. The difference in salinity at points more or less removed from the ocean is clearly shown by the data; as is the smaller amount of chlorine, or, as may be said, sea water, on ebb tide than on flood tide. Several series of samples collected at different depths and at different points show that the saltest water generally lies at the greatest depth. There were 802 samples of water analyzed for chlorine in 1907. Until a certain date the samples were collected at the same time as, though they were not identical with, the samples collected for analysis for bacteria. After that date determinations of chlorine Were omitted. The samples were all taken between January 8 and September 17, 1907. They were collected at different depths down to 100 feet below the surface of the water. (b) Intcrinixture of Sea and Land Water. — The sea water appears to have been thoroughly mixed with the river water in the samples collected at the Narrows, Kill van KuU and lower East river; but in samples collected in the Upper bay, in the Hudson river near the Battery and in the Harlem river, considerably fresher water was found at the surface than in the depths below. During a freshet in the Hudson river the water at the mouth of that stream contained 2,870 parts of chlorine per million at the surface and 9,960 at the bottom. In other words, the water was nearly four times as salt at the bottom as at the top. This was on March 21, 1907. Yet the water at the surface was by no means fresh. Marked differences in salinity between samples of water collected at the same time at points removed from one an- 46 Other by a few yards, indicate that the sea water does not diffuse with the land water instantly the two come in contact, bnt that this intermixture is relatively slow. In the process of intermingling, large, strong currents of sea and land water seem to interlace themselves in an endless variety of ways. A number of charts and diagrams have been made which show the variations which were found in the amount of chlorine at different depths and at different points in the harbor. 4. LOSS ON IGNITION (a) Water. — The number of samples of water subjected to the test know^n as loss on ignition was 130. The samples were all collected in the ten days between October 18 and 28, 1907. The determination w^as made by evaporating a sample of the water to dryness, weighing, and then heating the residue to such a temperature as would volatilize such parts as could be driven off by heat. The difference between the weight of the residue before and after volatilization was called the loss on ignition. This test was once much employed by sanitarians to show the amount of organic matter in drinking water, but it has generally been given up as unreliable. The data obtained in these analyses have been plotted in graphic form, the results of three series of observations being used for this purpose : two from Newark bay and one from Gowanus canal. The figures in each series are lowest for the head of the bay and canal, where the pollution is known to be greatest. They are also lowest for the surface of the water in more than half the cases. Thus the loss on ignition gives directly opposite evidence from the bacteriological and other indications of pollution. Apparently in these cases the greatest loss on ignition oc- curred where the pollution was least. This result needs ex- planation, but none is forthcoming from the data. Regarded as a whole, it is unsafe to attach any importance at the pres- 47 ent time to the results of these analyses. It is possible, of course, that information which may be collected later may show that they have considerable value. (b) Solid Matter from the Bottom of the Harbor. — There were 566 samples of solid matter from the harbor bottom which were analyzed for loss on ignition, and they were col- lected between May 3 and October 28, 1907. The results are expressed in parts per million by weight of mud dried at 105^ Centigrade. The results have been collected into several series; one to show the data obtained from samples collected at different depths below the surface of the bottom of the Harlem river from Spuyten Duyvil drawbridge to Randall's Island and another along the Brooklyn water-front from Conover street to Clark street. As far as depth below the surface of the bottom is con- cerned, the analyses indicate that the amount of volatile matter bears no relation to the depth at which the sample was taken. The loss on ignition was not relatively the same at all depths ; it was sometimes greatest at the surface of the bottom ; some- times at the greatest depth reached below the surface, and sometimes at a point somewhere between. In this respect the figures for loss on ignition differ decidedly from the figures for bacteria. It will be remembered that the bacteria became fewer as the depth increased. The volatile matter found in the solid material taken from the harbor bottom varied about as did the numbers of bac- teria, judging by the two series of results which have been studied. As a rule the loss on ignition was relatively great where the bacteria w^ere comparatively numerous and the fig- ures for both bacteria and loss on ignition were small in the same localities. The loss on ignition was slight in samples of solid matter collected from the bottom of the Harlem river at Kingsbridge, and here the bacteria in the mud were com- paratively few. Again, the figures for both bacteria and loss on ignition are large for the lower Harlem. In a series of samples collected along the Brooklyn water-front both the 48 bacteria and loss on ignition were greater from point to point going north. 5. COLOR OF THE WATER. There were 907 determinations of color made, covering a period from January 8 to October 18, 1907. The samples were the same as used for other determinations, being taken from different places at different depths, at different times of tide, etc. In general, the color of the water appeared to vary with the relative proportions of sea and land water. It was highest in the Hudson river and Harlem river at Spuyten Duyvil and at the mouth of the Passaic river, and lowest at the Narrows. There was much color also at times off the sewers of South Brooklyn, in the Atlantic basin, Wallabout channel. Coney Island creek and Gowanus canal. The greatest arr\ount of color was found in Newtown creek, where the most trade wastes were noted. The results of the color determinations, when plotted, show a steady increase in color proceeding from the Narrows, with an average of 8^2, into the different arms of the harbor and the rivers. The water of the East river was less colored than the Hudson and perhaps less at times than the Upper bay. The water of the Harlem river was less colored than the Hudson, but more than the East River. The maximum figure for the Gowanus canal was 60, Atlantic basin 120, Wallabout channel 65, Newtown creek 1,300. If large numbers of bacteria are a satisfactory index of sewage pollution, then the color determinations are not con- elusive. With a figure of 120 for color in the Atlantic basin, the bacteria numbered 10,500; while in water discolored with sewage off Sixty-fifth street, Brooklyn, the color was only 30, with 808,000 bacteria. With a figure of 1,300 for the highest color found In Newtown creek, the bacteria numbered only 2,100, but the bacteria In this case may have been diminished by trade waste. 49 Any effect on color which may have been produced by the season is not so evident as in the case of turbidity. Still, there are two cases which illustrate a diminution in color from winter to summer. Off pier A in the Hudson river two color determinations made in January averaged 27.5; those made in February averaged 16.9; in March, 17. i; in July, 13.0. In the East river a series taken along the centre of the channel on j\Iarch 7 were more highly colored than other tests which were made in June and after. The color generally appeared to diminish with the depth. This was noticed in the Lower bay, Kill van Kull, Hudson river and Harlem river, but exceptions occurred which are not easily explained. It is possible that the exceptions may have been due to variations in the mixing of sea and land water by different currents. One series of results show a diminution in color in the Harlem proceeding from the Hudson river east, which is what one would expect. But another showed a maximum of color at the southeast end of the Harlem. A study of the probable color of the Harlem at different times of the tide has suggested an explanation of these phenomena. This explanation is that the whole current of water passing through the river has a point of least color at about the centre, with more color to the west than to the east, and again a diminu- tion at the east. The color does not seem to vary much with the tides, but at the Narrows the color w^as less with flood current than with ebb current. The color was higher near sewers, and a high result at one single point in the Harlem may be due to coloring matter from the Park avenue sewer, which was near the point with a favorable current. The effect of trade wastes seems much more marked, especially in Newtown creek, where samples were taken near points of discharge from manufactories. 50 6. TURBIDITY There were 870 determinations of turbidity. All were made from the same samples as those used for color. The turbidity results cannot be averaged, the variations at any one place being too great. As an indication of pollution the turbidity determinations are of little use. A turbidity of 2 in the Gowanus canal was found, while as much as 23 was found near Robbins Reef light. A turbidity of 2 was also found in the waters of New- town creek, Wallabout bay and Erie basin. Turbidities as low as I were found in the Atlantic basin. The maximum was 2,000 in Newtown creek, near a chemical works and sewer. The turbidity was greatest in the winter and spring, and suddenly fell off after June nth. A careful study of the rain- fall of the vicinity and the Hudson watershed affords no ex- planation of this change. The turbidity varied more with the season than with the rainfall. There were, however, well de- fined increases after rains, especially in the Hudson off Spuy- ten Duyvil. Two cases of greater turbidity with ebb current than with flood current occurred at the Narrows. The same occurred in Newark bay; the turbidity increased, passing north to the mouth of the Passaic river. The nearness of sewers to the locations of samples may sometimes account for much turbidity, as in the Harlem near Park avenue, where the color was also high. But a result of 3 was also found just south of the Sixty-fourth street sewer, Brooklyn. The greatest turbidity was in Newtown creek and Gowanus canal, but some high turbidities were also found near Ellis Island. No definite relation of turbidity to depth was clear. The turbidity w^as sometimes greatest at the bottom, sometimes at the top, sometimes in the centre of a channel, or at one side or near the centre. Perhaps the greatest turbidity generally occurred at the bottom, toward the sides of the channels. 51 E. The Flow of Tidal Currents as Studied by Means OF Floats I. METHODS Observations of the currents of the harbor by means of floats were made on 2"] days. They were made in seven gen- eral locaHties, as follows : Upper Hudson river 4 days Lower Hudson river 2 days East river 2 days Kill van Kull 2 days Upper bay exclusively 5 days Lower bay exclusively i day Both Upper and Lower bays 1 1 days 2^ days The first records are for February 23 and the last for July 22, 1907. The observations of floats cover, therefore, so far as season is concerned, the late winter, spring and summer. (a) Object of These Studies. — The float observations were made to trace the flow of the main harbor currents, to ascertain the course taken by sewage from the vicinity of important existing sewers, and especially the course followed by the harbor currents which flowed by the proposed outlet of the Passaic valley sewer. Observations were also made to determine the direction and rate of flow close along the shores of the harbor where sewage was then discharged. Many observations were made to determine where floats would be carried when started from a given point at dift'erent stages of tide. The floats were designed to show the paths of the cur- rents at a uniform depth of 5 feet below the surface of the water. The floats consisted of a wooden upright 8 feet long, 2 inches by 2 inches in section. At the bottom of the up- right were nailed four wings of sheet iron, each 24 inches 52 deep by 24 inches wide. A cork float was placed near the top of the upriglit and the whole was surmounted by a flag-. (b) Behavior of Floats. — The wind seems to have had little effect upon these floats, but it is worth noting that they frequently went ashore. In the East river and Hudson river the floats repeatedly sought the east bank. On such occasions the float was taken up and set out perpendicular to the shore at such a distance as seemed likely to insure a clear course for the future. No reason has been offered for this ground- ing of the floats, and such studies as can be made now of the probable behavior of the wind at the time the observations were made throw little light upon the matter. (c) Location of Floats. — In all cases the floats were at- tended by a small power boat, which warned off vessels and enabled records to be made from time to time of the location of the float. At first the location was determined by noting the proximity of docks, public buildings and other known points on land, but later the positions were ascertained by means of a sextant sighted upon landmarks. The results of these studies as given in the notebooks of the observers have been carefully plotted on maps, but great exactness has been impossible, especially in dealing with the data collected before the end of June, for until that time the positions of the floats were not recorded with accuracy. After about the first of July the positions were located by sextants. This permitted the results to be plotted with precision by the use of three-point protractors. 2. RESULTS (a) Flushing Action of the Tide. — Some interesting re- sults were obtained by starting floats near Robbins Reef light in Upper New York bay. Observations were made on 8 days. The farthest point north to which a float was carried by a flood current was Fifty-fourth street in the Hudson river, on March 5, 1907. The distance was about 8 miles, and was covered in 5 hours, 45 minutes. The farthest point south reached with an ebb current was about iij^ miles. This was on Februarv 26] the time consumed was 6 hours. 53 The minimum distance north covered during a complete flood tide was 6 miles; this was on July 17. The minimum distance south covered during an ebb current was something over 6 miles; this was on July 8. Observations were made to trace the movement of a float through a wdiole tide along the Brooklyn shore south of Go- wanus bay. A float started at the mouth of Gowanus bay P'ebruary 2^, 1907, was carried out to Romer Shoal light, a distance of about 12 miles, in 7 hours. A flood current carried a float from Fifty-sixth street, Brooklyn, on April 6, only about 2 miles northeast along the shore, occupying 5 hours in passage. This last record suggests that this part of the harbor may have an excess of current flowing south, but the observations were not sufficient to establish this point. It is to be noted that these two series of observations were made toward the end of February, when freshet conditions may have existed in the Hudson, bringing down an unusual volume of fresh water to the sea. Whether there is an excess of water flowing out of the bay at every tide was not shown by the float studies. No observations covered a complete tidal cycle. The longest series of observations covered 9 hours, 50 minutes. Four series of observations in the Lower bay, where a float was' carried out by an ebb tide and back by a flood tide on about the same path, showed that the distance covered in the two hours before the tide changed was about 70 per cent, greater than the distance covered in the first two hours after the time of low tide. The maximum distance a float w^as carried by an ebb tide in the different parts of the harbor was always greater than the maximum distance carried by a flood tide. The maximum velocity of a float in any locality always occurred on an ebb tide. It should be remembered that a greater velocity in one direction does not of necessity mean that a greater volume of water was passing in that direction. The distance traveled by a float set adrift at any point on a given stage of tide was not by any means always the same, but varied widely. (b) Maximum and Minimmn Distances Covered. — The longest distance covered during one tide in the Upper and 54 Lower bay alone was about 12 miles. This occurred on two days: February 23 and April 12, both during ebb tides. The shortest distance covered in a single tide was about 2 miles; this was during a flood tide, and the observations were made near the Brooklyn shore. The longest distance covered by a float in the Hudson river w-as 12K miles; this happened on July 19. The longest distance starting in the East river was I4j< miles ; this occurred on March 29. The longest time occupied by a float going in any general direction was 7 hours; this was during an ebb tide on Febru- ary 23. The shortest period of ebb current was 5 hours; this was on April 12. The longest period of flood current was 6}i hours; this was on March 5. The shortest was 5 hours; this occurred: on April 6 and 8. It is evident from these figures that the tidal period is not regular, but may vary considerably in duration. There- fore, the distance traveled by a float depends not only upon the velocity of the current, but also upon the period of time during which the velocity is maintained. Whether the main currents ahvays flow in regular and un- varying courses W'as not positively shown by the floats, but it seems fairly certain that they do not do so. Floats w-ere sometimes carried to different points when started from tlie same spot and on the same stage of tide. Starting from a point near Robbins Reef light, an ebb current carried a float dowai Ambrose channel to the southeast on two occasions, and at three other times southwest into the Lower bay. (c) Currents Near Shore and in Midstream. — That the currents move much more slowly near the shore than in mid- stream is shown by tw^o observations made in the upper Hud- son. A float was started on two occasions on an ebb current from the same point off Yonkers. One, started on July 19, in the centre of the river, covered 12% miles before the tide turned. The time consumed was 6j^ hours. Another started near the east shore three days later covered only about 6j4 miles in six hours. 55 Section III, Investigation Made by the Department of Water Supply, Gas and Electricity of the City of New York in 1904 and 1905 Studies of the sanitary condition of the water along the shores of Manhattan and Brooklyn were made by the City of New York in 1904 and 1905 in connection with the installation of an auxiliary fire service. The object was to determine whether the water was suitable for extinguishing fires and to determine the points where it would be best to locate the in- takes. The investigations were made in two periods : the first between March 2 and 13, 1904, and the second between Feb- ruary 3 and March 29, 1905. There were, in all, 383 samples of water collected. The samples were analyzed for numbers of bacteria, B. coli, free ammonia, albuminoid ammonia, nitrites, nitrates and chlorine. Most of the samples were taken 2 feet below the surface of the water. At seven places samples were taken at depths of from 4 to 25 feet. Some of the samples were collected close to the bulkheads, and the others between the shore and the outer ends of the piers, or from 200 to 700 feet outward. In interpreting the data the times of high and low water have been obtained from automatic tide gauge records kindly supplied by the Department of Docks and Ferries. From these records estimates have been made of the probable currents. The samples along the Brooklyn shore were taken between Gold street and the basin near Beard street. The samples near the Manhattan shore were collected from the East river between James slip and East Seventeenth street, and from the Hudson river between Chambers street and West Twenty- second street. These localities have since been visited and a careful study has been made of each situation for the pur- poses of this report. 56 Notwithstanding the care taken to interpret the results, the data add Httle to the information from other sources. In fact, a considerable part of the data contradicts information otherwise collected, and the figures sometimes contradict themselves. Some samples appear to have been free from sewage, which, from other information, would seem to have been polluted, and vice versa. For the first and only time in the records of analyses of the harbor waters, the currents flowing toward the sea contained more ocean water than the currents flowing from the sea. A. Bacterial Results I. NUMBERS OF BACTERIA The numbers of bacteria were notably large in the East river from the Brooklyn bridge eastward and greatest during the ebb current. This result seems reasonable since large Cjuantities of sewage are discharged into the East river and more to the east of Brooklyn bridge than west of that point. (a) Variations in Numbers. — The hourly variations in numbers of bacteria found in the more open parts of the harbor by the Metropolitan Sewerage Commission in 1907 do not seem to have existed in the waters along the piers and bulkheads. A noticeable feature of the analyses for bacteria is the variation in numbers found at the same place on different occasions. An example of this occurred in the records of analyses of water from the foot of Houston street. Here the maximum number of bacteria was 48,000 and the minimum 600. The probable explanation of this difference lies in the fact that a large sewer discharges into the river at Clarkson street a few hundred feet away. It is likely that changes of current due to differences in tide led to the difference noted. Another instance of a marked difference occurred at Gold street, Brooklyn. Here the maximum number of bacteria was 98,000 at a depth of 10 feet below the surface of the water, while the minimum was 1,310 at the same depth. There is 57 also a sewer discharging at the foot of this street and the differences in the numbers of bacteria were probably due to differences in the pollution produced by the sewage as it was carried to and fro by the currents. In this case and the pre- ceding one the condition of the water noted must have been temporary; in fact, the quality of the water along all the docks and wharves where the sewers discharge is probably changing constanth^ The extent of these changes is w^ell indicated by the fact that a range of 600 to 28,000 bacteria occurred on one day at one place. Another interesting feature of the data is the fact that the number of bacteria was sometimes smaller in the immediate vicinity of sewers than at a distance from any polluting source. The conditions at Oliver street, Brooklyn, may be cited as a case where the water was much freer from sewage than a knowledge of the surroundings would lead one to ex- pect. For example, the largest number of bacteria found on an ebb or flood tide off pier 33 at the foot of Oliver street, Brooklyn, was 10,000, although a sewer discharges within a few^ hundred feet under pier 34. It is possible that this small number could be accounted for by the fact that the sev/er outlet is situated farther from shore than the point where the samples were taken, so that the sewage was rapidly carried away. Small numbers of bacteria were also found at pier 20, foot of Chambers street, Hudson river, although the presence of a sewer under the next pier to the north and the finding of visible traces of sewage along one side of pier 20 would lead one to expect large numbers of bacteria. A similar condition, difficult to explain, seems to have existed when the samples w^ere taken at Hamilton avenue, Brooklyn. (b) Complexity of Conditions. — Studies made of the path taken by sewage as it flows from the sewer outlets into the rivers of New York harbor have shown that there is no regu- larity about the course followed. The stream of sewage seems always to lie at or near the surface of the water into which it is discharged. It may flow in one direction for a few mo- 58 ments and then follow an entirely different course, preserving its identity for a long period. (c) Conditions at Bulkheads and Pierheads Compared. — Four series of samples were collected to show the conditions which occurred simultaneously at bulkheads and pierheads. These series were made at three different places. At the foot of Joralemon street, Brooklyn, the bacteria were, on two occasions, fewer in number proceeding from the bulkhead out to a point beyond the pierhead. This result is explained by the fact that a sewer discharges at the bulkhead at this point. Different results were obtained at the foot of Cham- bers street, Hudson river, and Oliver street. East river. Here the bacteria were more numerous at the pierheads than at the bulkheads. At these points there are no sewers at the bulkheads, but sewers discharge at two points in the imme- diate vicinity — Duane and Oliver streets, where outfalls are located near the pierheads. (d) Relation of Depth. — The relation of depth to the numbers of bacteria 'is indicated by the results of samples taken at 7 places at depths of 2 feet and more below the surface. At two places the numbers were, on the whole, greater near the surface than below. At five places the num- bers were greater at greater depths. It will be noted that this result is contrary to the result found generally in 1907 by the Metropolitan Sewerage Commission. B. Comparison With Other Analyses When the analyses made by the Department of Water Supply, Gas and Electricty in 1904 and 1905 are compared with the analyses made by the Metropolitan Sewerage Com- mission in 1907, some interesting facts become evident. De- terminations of numbers of bacteria in the water were made at four points by both the authorities mentioned, namely, at Oliver street, Gansevoort street, Conover street and Coney Island creek. At the first three of these places the bacteria 59 were greater in number in 1907 than formerly, but more bac- teria were found in Coney Island creek in 1904 than in 1907. It is not certain, however, that the conditions under which these samples were taken were such as to make the results, strictly comparable. To give some idea of the numbers of bacteria found at Oliver street, Manhattan, Gansevoort street, Conover street and Coney Island creek, a few more details of the analyses may be of service. At the foot of Oliver street at the inner end of the slip, the number of bacteria i foot below the sur- face was 17,000 during a flood current in 1907. In 1905, two samples taken at the bulkhead of pier 2,3, at the foot of Oliver street, at about the same tidal stage, gave counts of 2,360 and 1,960. At the foot of Gansevoort street in 1907 the number of bacteria during a flood current was 9,500; in 1905 the num- bers ranged from 330 to 1,500 with a flood current. During an ebb current in 1907 the bacteria numbered 8,500, while in 1905, under similar conditions, the numbers ranged from 780 to 2,610. At the foot of Conover street, Brooklyn, the count in 1907 was 8,100 during an ebb current; in 1904 the numbers ranged from 1,010 to 1,420, with probably a flood current. For Coney Island creek in 1907 the count was 10,500, soon after low water; in 1904 the average of the series of samples taken at about the same stage of tide was about 12,500, w^ith a maximum during the flood current of 30,000. Another series gave a range of 710 to 15,000. 2. COLI IN THE WATER The results of the coli determinations follow, in a general way, the results obtained in estimating the numbers of bac- teria in the water, except that there were many times, when no coli were found, when the numbers of bacteria and the free and albuminoid ammonias in the water would lead one to the opinion that heavy pollution existed. In one series of 185 determinations made from samples collected along the 6o Hudson and East river docks, there was no evidence of the colon bacilkis in 56 per cent, of the cases. At the foot of Houston street no indications of the bacilhis were found five times out of seven, although the numbers of bacteria and the amounts of free and albuminoid ammonias were large. C. Chemical Results I. FREE AMMONIA^ ALBUMINOID AMMONIA^ NITRITES AND NITRATES The analyses for free and albuminoid ammonia, nitrites and nitrates, add little to the knowledge available concerning the condition of the water. Taken together with determina- tions of the numbers of bacteria they are sometimes in con- flict with themselves as to the proof of pollution — one class of data indicating pollution, while another does not. In a series of observations made every day for one week at the foot of Joralemon street, Brooklyn, the results were particu- larly conflicting and confusing. In view of all the circum- stances it seems unwise to attempt to draw inferences from these data. 2. CHLORINE The determinations of chlorine have given results which are also difhcult to explain. The amount of chlorine often appears to have been greater when the current was flowing toward the sea than when it was flowing from the ocean, a result so at variance with what has uniformly been observed in all the other data that no explanation of it can be given. 6i Section IV, Investigations Made by Charles F. Breitzke in 1906 of the Sanitary Condition of Qowanus Canal* A study of the sanitary condition of Gowanus canal was made in 1906 by Charles F. Breitzke. The results of this study were submitted by Mr. Breitzke in the form of a thesis which was offered in partial fulfillment of the requirements for the degree of Bachelor of Science. An abstract of this thesis appeared in the " Technology Quarterly/' Boston, Vol. XXL, No. 3, September, 1908. It is mainly from this account that the following notes are taken. The statements of data and opinion are those of the author of the thesis. The work done was divided into three parts : A, Sanitary Survey ; B, Analyses ; and C, Discussion of the Data. The total number of analyses recorded in the paper is about 40 ; 30 more are referred to but are not reported in detail. The analytical work was done at the Mount Prospect Laboratory, Brooklyn. A. Sanitary Survey Gowanus canal, with its various branches or basins, is about two miles in length, about 100 feet wide, and averages 10 feet in depth. It is closed at its upper end, and its lower end opens upon that part of Upper New York harbor known as Gowanus bay. The immediate shores of the canal are occupied by fac- tories, including chemical works, gas works, oil refineries, salt works, ice plants, asphalt and paving material plants, building material yards, coal and wood yards, power houses, machine shops and foundries, storage warehouses, junk yards and city refuse dumps. The assessed value of the land fronting the canal Is $3,315,000. An average of 87 vessels pass in or out of the * An investigation of the sanitary condition of the Gowanus Canal, Brooklyn. New York. By Charles F. Breitzke. Printed in the Technology Quarterly, Vol. XXI., No. 3, pp. 243-279. September, 1908. Boston, Mass. 62 canal each day. Immediately adjoining the commercial sec- tion which borders the canal is a thickly populated tenement district, with better class residences at a distance of a quarter of a mile or so. The waters of the canal are polluted by the drainage of the industrial plants on its shores, by six so-called storm water sewers, ranging from y2 inches to 90 inches in diam- eter, carrying more or less house sewage, and by six sewers for household drainage, ranging from 12 inches to 48 inches in diameter. At the very head of the canal is a relief sewer, 15 feet in diameter, which, although intended to accommo- date only storm water, discharges house sewage and slaugh- ter-house drainage. The canal is constantly filling up, as may be judged from the fact that in the 27 years between 1875 and 1902, $42,- 092.20 were spent for dredging. At the time of this study the canal had filled so much at its upper end that barges went aground, and the water was said to be of inadequate depth for fire boats. The only water which enters the canal and is available for flushing it out flows in from the harbor, except after heavy rains, when the water discharged by the storm sewers pro- duces a little current. The surface of the w^ater in the canal is covered with oil, coal dust, and a scum consisting in part of human feces. Below^ the surface the water is black, warm and foul. Gases constantly bubble up through the water. The stench is heavy, especially in summer, and is noticeable at all times at a dis- tance of several hundred feet from the canal. Under certain conditions of weather large sections of the city to the north- east and east are affected by the odor. Fish have not been caught in the canal for many years. In short, the canal is an open sewer, or, rather, an open septic tank. The canal water is devoid of oxygen, and, in consequence, solid matter which is deposited from the sewers putrefies and gives off offensive odors. The trouble arises chiefly from the presence of house sewage, although the in- dustrial drainage is partly to blame. 63 B. Analytical Results The results o£ the analyses ^represent the examination of two series of samples. It was intended that they should be collected throughout the length of the canal in such a way as to give a good indication of this water in its entirety, as well as in its various parts. The first series of samples was taken February 3, 1906, when there had been no rain, and was believed to represent the average conditions which occur under such circumstances The second series was taken April 16, 1906, after a rain- storm, which had carried a considerable amount of street and other surface water through the sewers into the canal. This second series, therefore, was believed to indicate the condi- tion of the canal when stirred up. The samples were collected from a rowboat, the water being taken at different depths and at different points across several cross-sections of the canal. The water was always collected into a large bottle provided with a double perforated stopper. The contents of the bottle ^vere then emptied into a pail and mixed, and a litre bottle was filled from the mix- ture. By this method a sample representing the average qual- ity in different cross-sections of the canal was obtained. As soon as the samples were collected for the whole series they were taken to the Mount Prospect Laboratory, which was within 20 minutes' ride of the canal. With the exception of the test for turbidity, the methods of analyses were those recommended by the committee on standard methods of water analyses of the American Public Health Association. In the first series, consisting of 1 1 repre- sentative samples, the following determinations were made: turbidity, total organic nitrogen, free ammonia, chlorine, oxygen consumed, number of bacteria developed in a beef gelatine medium after 48 hours at 20^ C, and B. coli. The second series, consisting of 15 representative samples, were analyzed in the same way as the first, except that there was a distinction made between the organic nitrogen, solid matter and organic matter carried in solution and suspension. 64 The oxygen consumed was determined by the five-minute- boil method, the total nitrogen by the Kjeldahl and the free ammonia by direct nesslerization. The turbidity was deter- mined by means of the Jackson turbidimeter. C. Discussion of Data The data collected have been plotted, and it is interesting to compare the results of the two series of curves. The re- sults are such as might have been expected. The canal was shown to be badly polluted, and house sewage was found to be more objectionable than industrial drainage. The second series showed less pollution at the head of the canal than did the first series, but there was more evidence of pollution elsewhere. This was understood by the investigator to mean that the storm water had pushed the household sewage down from the head of the canal tow^ard the mouth. In examining the data closely the effects of pollution by some of the drains and sewers can be seen at the different parts of the canal where these outlets occur. Interesting correspondences are observable in the rise and fall of the figures at different places in the curves for organic nitrogen, oxygen consumed, turbidity, total solids and bacteria. The bactericidal action of some factory wastes seem to be detect- able, as is the precipitating action of other wastes. From the analytical data it appears that the water at the head of the canal is about two-thirds as strong as Brooklyn sewage. The proportion of sewage is reduced to about one- tenth near the mouth of the canal. The sample of sewage upon W'hich the foregoing calcula- tions are based and upon W'hich other computations to be noted presently depend, was taken from a manhole at the corner of Xevins and Butler streets, Brooklyn, on Saturday morning, April 14, 1908, the depth of flow in the sewer at the time being 6 inches. The sewage w^as analyzed like the samples of water; its putrescibility was tested by the methy- lene blue test. By this test one cubic centimeter of a i/io per cent, solution of methylene blue is added to a number of 65 mixtures of about 250 cubic centimeters of sewage and dif- ferent quantities of tap water. When putrefaction occurs the blue color disappeared. These tests indicated that a dilution of one part sewage to 15 parts water were necessary in order to supply the oxygen required to oxidize the sewage, or, in oth^r words, insure a non-putrescible mixture. About 30 samples of canal water were analyzed for dis- solved oxygen, finding with few exceptions none present. The temperature of the water of the canal w^as always warm, for the reason that much hot water was discharged into it by industrial plants. The temperature in February was 65° Fahr. at the head of the canal and gradually in- creased for about 1,500 feet down stream to 70°. In the next 500 feet toward the mouth, the temperature rose to 90°, further on it dropped to 70°, and then fell slowly until, at the entrance to the bay, it was 44°. In April the tempera- tures were a little higher, but varied in the same way at dif- ferent points. Gases bubbled up through the water for practically the whole length of the canal, and masses of black solid matter rose to the surface, burst, liberating these gases, and then disappeared from view. Some samples of solid matter from the bottom of the canal and various points in Gowanus bay were collected and anal3^zed with results w^hich were confirmatory of the prin- cipal data already referred to. Not the least interesting part of this study of the condi- tion of Gowanus canal is an attempt to calculate from the analytical data obtained the proportion of sewage, land water and harbor water in the canal at various points. Calculations also were made as to the amount of w^ater which it would be necessary to mix with the sewage of the canal in order 10 render it odorless, provided (a) that no more sewage was to be added, and (b) that sewage w^as to be allowed to continue to flow in. From these calculations it appears that one volume of sewage would have to be mixed wdth 15 volumes of harbor water containing about 75 per cent, of the amount of oxygen 66 which the harbor water would contain if saturated to prevent putrefaction. Assuming that 793,000 cubic feet of sewage were discharged into the canal every day, 11,895,000 cubic feet of harbor water would be required to render the mixture inofYensive. Allowing a factor of 2 for safety, the author reached the conclusion that 25,000,000 cubic feet of water would have to be pumped daily into the canal to dilute the polluted water to such a point as to render it non-putrescible. If sewage was kept out of the canal as far as practicable, 1,500,000 cubic feet per day would be required. At the time of these studies it was estimated that the canal water was about 50 times as polluted as the water of the harbor adjacent to the mouth of the canal. These calculations need not be divScussed here, for it is the main result which may or may not be useful, and not the method of calculation. The calculations can themselves be seen on examining the original paper in the '' Technology Quarterly." Using the results referred to, showing the composition of Brooklyn sewage, it appears that at the head of the canal the water contained at the time of this investigation 65 per cent, of sewage, 34 per cent, of land water, and i per cent, harbor water. The average for the whole canal w^as 25 per cent, sewage. 67 Section V, Investigation of the Waters of the Lower Hudson River by the Burr=Hering= Freeman Commission in 1903* The object of this investigation was to obtain data which would be of service to a board of engineers appointed by the City of Xew York in 1902 to report upon the most available means of increasing the drinking water supply of the me- tropolis. Like the report of the board itself, the studies le- ferred to here were of an exhaustive character. They related chiefly to inland streams, but considerable attention was given to the Hudson as a possible source of drinking water. A. Hydrographic Features I. THE HUDSON RIVER The Hudson river rises in the Adirondack mountains and flows in a southerly direction for about 300 miles, emptying into Xew York harbor. Its influence, however, does not end in the harbor, but is detectable in the waters of the Atlantic ocean some miles off the coast. The river has a total drainage area of about 13,200 square miles. At Troy, a few miles below the confluence of the Mo- hawk, is the State dam, and at Glens Falls, about 40 miles above the Mohawk, the river flows over a high ledge. These two points, Glens Falls and Troy, divide the river into three * Appendix \'I., by George C. Whipple, to Report of the Burr-Hering-Freeman Commission on Additional Water Supply for the City of New York, made to Robert Grier ^lonroe. Commissioner of Water Supply, Gas and Electricity, November 30, 1903. Printed by Martin B. Brown Company, City Printers, New York, 1904, pp. 501-530. 68 sections, namely, the upper Hudson, the middle Hudson and the lower Hudson. The term " upper Hudson " stands for mountains and forests, " middle Hudson " for manufactories and agriculture and " lower Hudson " for commerce. In a general way it may be said that the upper Hudson contributes coloring matter to the water, the middle Hudson hardness and pollution and the lower Hudson pollution. (a) The Hudson as a Source of Drinking Water. — The most important feature of the lower Hudson is its tidal char- acter. This portion of the river is really an elongated arm of the sea, where the tide ebbs and flows even to the foot of the Troy dam, 150 miles from New York. This does not mean, as is commonly supposed, that sea water reaches the Troy dam, but only that at that point the surface of the water rises and falls under tidal influence. The necessity for determining the icffect which the sea water might have upon the saltness of the Hudson at the point where, for engineering reasons, it might be desirable to obtain drinking water for the! City of New York, led the author to inquire into the salinity of the Hudson from the open ocean to Troy. It was well known that the Hudson water occasionally became brackish at Poughkeepsie and it was almost unani- mously the opinion of rivermen that the water was always fresh and drinkable at Kingston. No data were in existence from which to learn the conditions which allowed sea water to run up to Poughkeepsie and beyond. Therefore steps were taken to obtain these data as completely as possible within the time and means at the disposal of the investigators. In examining this report the fact must clearly be kept in mind that the author's point of view was that of one who was regarding the condition of the Hudson as a possible source of drinking w^ater. The report does not purport to include a thorough study of the movement of water in the Hudson river or the problem of sewage disposal, but some of the data are nevertheless of service in connection with the investigation of these subjects. 69 (b) Depth and Width of the Hudson. — The present mouth of the Hudson river is at the Battery, which is at the lower end of Manhattan Island, but the ancient bed of the river can be followed for a great distance beyond the harbor along the bottom of the sea. At the Battery the river has a width of about 5,000 feet and is about 60 feet deep at the deepest point at mean low tide. This depth is maintained with but slight variation to Hastings, about 20 miles. Opposite Fort Washington, 10 miles above the Battery, there is the first of a series of deep pockets which are thence- forward found at intervals for many miles along the course of the river. The deepest place in the Fort Washington pocket is about 150 feet below^ the surface of the water. Above Fort Washington there are three well-marked pockets; at Haverstraw a pocket 100 feet deep; at Peekskill a pocket 170 feet deep, and at West Point a pocket 210 feet deep. Further up the river, between 66 and 90 miles from the Battery, several other pockets occur, but these are of less depth than those just mentioned. A short distance above Hastings the river widens to about three miles and forms what is known as Tappan Zee and Haverstraw bay. At the upper end of Haverstraw bay the maximum depth is about 30 feet. Between this point and Cornwall, 56 miles above the Battery, the river passes, wath several curves, through a mountainous section of country called the Highlands. Here the stream becomes deep and narrow. Above Kingston, 91 miles from the Battery, the river becomes somewhat wider, but is of less and less depth, until at Albany the water is about 15 feet deep. (c) Cubic Capacity of the Hudson. — The cubic capacity of the bed of the Hudson river below the level of mean low water was calculated from charts issued by the United States Coast and Geodetic Survey. These capacities were calculated for every lineal mile of the river from the Battery upward and indicate that the volume of the Hudson below mean low water level ranges from 375.000,000 cubic feet to 1,427.000,000 cu- bic feet per mile for that part of the Hudson river which lies 70 between the Battery and a point 107 miles beyond. For a dis- tance of 30 miles above the Battery the volume of the Hudson per lineal mile ranges from about 600,000,000 cubic feet to about 1,000,000,000 cubic feet. (d) Discliar gc of the Hudson. — Computations were made to show the volumes of land water discharged by the Hudson river at the Troy dam and at the Battery. The season was an unusually wet one, with a short dry interval. At one time in March the flow of water over the Troy dam was estimated at 101,000 second feet and the discharge at the Battery 150,000 second feet. In May, which happened to be a dry month, the minimum yield at the Troy dam was esti- mated at 3,000 second feet, and at the Battery 4,200 second feet. In connection with this subject it may be well to note that, owing to frequent rains through the summer, the river never shrank to its usual dry weather volume. In conse- quence of this fact the salt water from the sea did not run as far up the Hudson river as usual. 2. TIDAL PHENOMENA (a) Tidal Ranges in the Hudson. — The water of New- York harbor rises and falls through an average of 4.8 feet with the tide. At Albany the average range is about 2.5 feet. Be- tween Albany and the Battery the range varies considerably according to locality. The mean tide level at Albany, excluding flood conditions, is about 2.5 feet above the mean sea level of New York harbor. From Albany down to a point near Rhinecliff, about 90 miles above the Battery, the river, under ordinary conditions, has a gradually decreasing slope, which averages about .03 foot per mile. Below Poughkeepsie the mean tide level increases slightly to Oscawana, about 40 miles above the Batter}'. At this point the average rise and fall decrease to New York har- bor. The author inferred from these facts that the influence of the salt water would not be felt in the third section of the river, where the slope or mean tide level was seaward. The lower boundary of this section was in the neighborhood of Rhinecliff. 71 (b) Duration of Tidal Periods. — It took about 9 hours 50 minutes for the crest of the tidal wave to run from the Narrows to Albany, but the troughs of the waves move more slowly, requiring 11 hours 12 minutes to reach Albany. This difference was due to the flow of the stream. In New York harbor the ebb and flood of the tide were of about equal duration. Proceeding up the river the duration of the ebb tide increased until at Albany the tide fell for 7 hours 18 minutes and rose for 4 hours 42 minutes each half day. When the crest of the tidal wave reached the Troy dam it receded, and at a certain point down the river it met the advancing crest of the next wave. In a similar way the troughs met. (c) Effect of Wind on Tide Level. — It was found that the wind exerted an important influence upon the level of tide in New York harbor and the Hudson river. The wind blow- ing for several days from the east at a velocity of 20 miles per hour would tend to raise the tide level more than a foot above what it otherwise would have been. For a con- siderable distance up the river the east and west winds exerted a greater effect upon the tide than the north and south wands. During April, 1903, when a strong east wind blew for four days, the mean tidal level was raised 2.5 feet in the harbor and 1.5 feet at Poughkeepsie. At times the effect of the wind more than outweighed the effect of the astronomical conditions which ordinarily governed the height of the tide. B. Studies of Salinity I. THE SALT OF THE SEA (a) Chlorine. — Ordinary sea water collected off the coast opposite New York at such distance as not to be affected by fresh water from land was found to contain about 18,500 parts per million of chlorine. In the harbor the chlorine was less than this; seldom exceeding 16,000. It was less than 10,- 000, even at the Narrows. That is, the harbor water was con- sidered by the author to be only about one-half sea water and was seldom more than 85 per cent, as salt as the sea. 72; A table was prepared to show the results of analyses of samples of sea water collected from a steamship which passed tlirough the Mediterranean Sea, near the coast of Portugal, among the Azore Islands, through the Gulf Stream and near the American coast. The chlorine in these samples ranged from 17,800 in a sample collected 25 miles off the Atlantic coast to 21,350 parts per million in the Mediterranean Sea, 25 miles oft* the coast of Italy. A second set of samples was collected from a steamship plying between New York and Portland, Me., and passing through Long Island Sound. These letter samples ranged from 12,075 to 18,475 parts of chlorine per million. The least amount was found in a sample collected just outside of Plell Gate, New York harbor, and the largest in a sample col- lected about 40 miles east of Cape Ann. The author quoted Mr. H. W. Clark, Chemist to the Committee on the Charles River Dam, Boston, Mass., to show that a sample of water collected 6 miles east of Boston Light off the Massachusetts coast contained 18,130 parts of chlorine per million. (b) Mineral Ingredients of Sea Water. — The author gave the results of a mineral analysis of sea water as deter- mined by Prof. Vivian B. Lewis, which showed that a large part of the salt in sea water was sodium chloride or common table salt and that magnesium chloride furnished about 10 per cent, of the total saliue content. The results of this analysis follow, the constituents being stated in parts, by weight, of ingredient per million parts, by weight, of water : Sodium chloride 26,430 parts Magnesium chloride 3 J 50 Magnesium sulphate i>7^3 Calcium sulphate i»330 Silica . 120 " Calcium carbonate 56 Magnesium carbonate trace Oxide of iron trace 32,869 7Z While this analysis is far from complete it serves to give an idea of the most important constituents of sea water. 2. SALTNESS OF THE HUDSON (a) Changes in the Salinity. — During the month of March, 1903, the Hudson river was in flood. Samples col- lected at this time showed that the chlorine ranged from about 1 1.3 to 21.3 parts per million at Hastings, 22 miles from the Battery. So far as salinity was concerned, this water could almost have been used for drinking purposes. About the middle of April the discharge of the river began to fall off rapidly, and during May, because of the drought, it continued to diminish. This permitted the sea water to run up the river. From March 23 until the middle of September a series of samples was collected almost every week from New York City to Poughkeepsie, at intervals of about one mile. Generally one sample was taken at high tide and one at low tide. The sea water ran furthest up the river during the last of May and the early part of June before the heavy rains of summer came on. On May 28 the water about 9 miles below Poughkeepsie was submuriatic, that is, it contained from 5 to 20 parts per million of chlorine — an amount which is detect- able by the sense of taste. When the discharge of the river increased in June the brackish water was forced down the river to Fort Washing- ton, New York City, and submuriatic water was not found above the Tappan Zee. Later in the year the brackish water again forced its way up the river. The water was submuriatic as far as West Point, 52 miles from the Battery. But at no time was there so much sea water at Poughkeepsie as to make the river unsuitable as a source of water supply. The foregoing figures all refer to surface samples and, for the most part, to samples collected near the centre of the stream. (b) The Under run. — It is well known that more sea water runs up a tidal river at the bottom than at the surface 74 and that for this reason there is more chlorine in the water at the bottom than at the top. This phenomenon, known as the iniderrun, is especially notable in the Hudson. Observations were made by the author to determine the extent of the under- run in the Hudson river, but these results are not given in detail in his report. Some early studies of the phenomenon of the underrun of sea water in the Hudson river were made by Prof. Mitchell and H. L. Marinden and published in the reports of the United States Coast and Geodetic Survey for 1873 and 1887. In- vestigations on the subject of underrun in the Charles river, Boston, Mass., were also made by Mr. John R. Freeman in connection with investigations for the Charles river dam. The observations of the Hudson, made during the summer of 1903, showed that the phenomena were confined to those por- tions of the river where the chlorine was comparatively large in amount. On January 27, 1903, samples of water were taken at dif- ferent depths at Fort Washington, New York City, the tide being three-quarters ebb. At the surface there were 5,900 parts of chlorine per million; at 30 feet 8,900 parts, and at 55 feet, the bottom of the river, 12,300 parts. (c) Sanitary Importance of the Underrun. — The phe- nomenon of the underrun was of interest from a sanitary standpoint for the reason that it was thought the salt water of the sea, running up stream at the bottom of the Hudson 1:hrough the polluted harbor of New York, might carry sewage matters with it. In the early government studies of the underrun of the Hudson much stress was laid upon the possibility that the pockets or potholes in the river bottom might accumulate sewage, and that this sewage might be left unchanged when the underrun retreated toward the sea. The author investigated this matter. On January 17, 1903, the water in the Peekskill pocket had one to two parts of chlorine at all depths down to 125 feet. The same was true of the West Point pocket, which was 180 feet deep, and the Newburgh pocket, which was 80 feet deep. On January 22 the Poughkeepsie pocket, 60 feet deep, 75 contained 2 parts of chlorine at all depths. On February 11 samples were taken every 10 feet from the surface to a depth of 90 feet in the Newburgh pocket, and the chlorine was 1.6 parts per million in all cases. On the same day the chlorine in the West Point pocket varied from 1.2 in the centre to 1.4 at the bottom. In June, after the sea water had run for a con- siderable distance up the river and then retreated, all the pockets were investigated and found to contain no large amount of chlorine. (d) Salinity at Different Points Across the Stream. — ■ Samples taken at various points across the stream and at different times showed that there was more chlorine near the shore than at the centre. These differences were not great, however, except during ebb tide, when the strongest outflow was passing down the main channel. At times during flood tide the water in midstream contained more chlorine than was found elsewhere. (e) Changing Nature of the Problem. — The author had desired to establish the relation between the tidal and hydro- graphic conditions of the Hudson river but found it a diffi- cult matter as the phenomena were subject to many complica- tions. He found the controlling influence upon the underrun of sea water to be the stream flow. The tide exercised but a secondary influence, although daily fluctuations in the saltness of the water might be caused thereby. The quantity of water flowing over the Troy dam and from the watershed of the lower Hudson determined the salinity of the river at all points. Ordinarily the late summer, when the stream flow was least and the general tidal elevations of the harbor highest, was the most favorable time for a high run of sea water. C. Pollution of the Hudson (a) The Authors Point of Viezu. — That the Hudson river was polluted was in no need of scientific demonstration. Yet the ocular evidence of this fact was abundantly confirmed bv chemical and bacterial analvses of the water and bv statis- 76 tical data of population and the prevalence of typhoid fever on the watershed. In considering the use of the term " pollu- tion " by the author, his point of view must carefully be kept in mind. He was considering the possibility that the water would be used for drinking purposes. (b) Method of Study. — Data wxre collected at all the im- portant centres of population on the watershed above Pough- keepsie- covering the nature of the water supplies, the sewerage systems, the character and extent of the industrial establishments and the nature of the resulting waste products. From the sanitary standpoint the most important sources of pollution were the sewers of the large cities, for these di- rectly contaminated the water with fecal matter. Most of the large cities were provided with sewers and practically all the manufacturing establishments situated near the stream had water closets which discharged directly or indirectly into the water. The urban population per square mile of watershed was considered to furnish, therefore, a fair index of the degree of pollution of the stream. (c) Population on the Drainage Area. — The figures indi- cated that the total rural population on the drainage area of the Hudson river in 1903 was about 900,000 above Yonkers, which lies just above New York City. The total urban popu- lation to this point was about 650,000. The rural population down to Poughkeepsie was 750,000; the urban population 500,000. To Troy the estimate was 550,000 for the rural population and 350,000 for the urban population. The urban population per square mile of drainage area varied from about 40 to 55, and the rural population about 60 to 80 per square mile. Both the urban and rural concentra- tions of population were considered to be greatest near the mouth of the river and near Troy, and least about midway between these two points. (d) Typhoid Rates. — The prevalence of typhoid fever on the watershed, and especially in the several towns, was thought to have a marked effect upon the character of the water as 77 regards pollution. Of two sewered cities equal in size that one would be the more dangerous which had the higher typhoid death rate. For the upper Hudson river drainage area the rate varied from about 9 to about 233 per 100,000 popula- tion. ]\Iost of the figures were averages for the 9 years 1894 to 1902, inclusive. (e) Danger of Pollution. — The author considered that the pollution should not be regarded as cumulative. That is, the danger from the water did not increase in the same propor- tion as the distance from Albany toward New York increased. He was of opinion that the degree of pollution of the river be- tween H3^de Park and Kingston was no greater than it was above the city of Albany, where the water was taken and filtered for a public drinking water supply. That it did not become more and more polluted was due to the fact that the addition of relatively pure water to the river from the water- shed more than made up for the sewage which w^as added. In the foregoing statement no account was taken of the possibility that polluting matter might be carried up stream from New York harbor and cities and towns along the lower river. The author considered that an intake for a drink- ing water supply w^hich was so located as to be above the north- erly limit of sea water inflow would practically escape the danger of sewage pollution from New York harbor and would, in fact, be but slightly affected by any pollution which would occur between the intake and the sea. Nevertheless, if Hudson river water w^as to be used for drinking purposes by New York City, it would be wise to provide all the cities of the lower Hudson with systems of sewage disposal in order to reduce the danger of infection to a minimum. ys Section VI. Investigation of the Condition of the Passaic River by Messrs. Hazen and Whipple in 1906 The report here referred to was made to a joint committee of citizens and of the board of aldermen of Paterson, N. J. The report gives Mr. Hazen's opinion of the best means of disposing of Paterson's sewage without polluting the Passaic river. Paterson w^ished to know whether it would be better to purify its sewage or join with other municipalities in the Passaic valley in the construction of a trunk sewer to dis- charge into New York harbor. In the course of his investigations Mr. Hazen called his partner, George C. Whipple, to his assistance. Mr. Whipple made analyses of the Passaic river water and entered into an elaborate discussion of the quantity and quality of sewage from Paterson then being discharged into the Passaic river. The following remarks are drawn from Mr. Hazen's report and Mr. Whipple's appendix to it, which were published by the joint committee. The population of Paterson at the time of these studies was about 133,000. It was estimated that it would be about 300,000 by the year 1938. The condition of the Passaic river and the disposal of the sewage of Paterson have a bearing upon the condition of New York harbor for the reason that the Passaic flows into Newark bay, an arm of New York harbor. A. General Discussion of the Problem by Mr. Hazen^ I. THE manufacturing WASTES The manufacturing wastes were greater in volume than the domestic sewage of Paterson. They added materially to * Report of Allen Hazen to the Joint Committee on S swags Dispc-al. Paterson. N. J., June 30, 1906. See The Joint Committee on Sewage Disposal of the City of Paterson, printed by the Chronicle Print, Paterson, 1906, pp. 63-107. 79 the pollution of the river. Some of these wastes were carried through the city sewers, but the greater part were discharged directly into the river. (a) Dye House Wastes. — In the dye houses of Paterson there were handled every year about 7,500,000 pounds of raw silk, which was two-thirds of the whole amount manufactured in the United States. In handling this material the dyers esti- mated that 1,000 gallons of water was used for every pound of silk. This was 20,000,000 gallons per day, or 200 gallons per capita for the entire population of Paterson. For every pound of raw silk one pound or more of soap was used. In the larger works the greater part of this soap was recovered, but a large proportion passed off with the wastes. In cleaning the silk there was removed a substantial amount of putrescible ex- tractive matter which contributed in a considerable degree to the pollution of the river. Various chemicals and dyes were used in the process of dyeing the silk. There was necessarily a large amount of loss, which the manufacturers endeavored to reduce as far as pos- sible. Of the polluting substances by far the greatest quantity was carried by a comparatively small volume of concentrated liquor, not exceeding 5 or 10 per cent, of the total volume of water used by the dye houses. Certain further quantities of discharge contained some pol- luting matters, but the great bulk consisted of wash water containing only mineral matters or organic substances in such small quantities that they did not offensively pollute the river. Owing to the fact that the water used in the dye houses was of exceptional purity and the wastes, chiefly mineral and not putrescible, the author was of opinion that the wastes from the dye houses did no material harm to the river. (b) Wastes from Various Industries. — There were 3 slaughter houses and packing establishments, employing 75 men; 6 breweries, making 230,000 barrels of beer and ale annually; 2 printing and dyeing establishments not dealing with silks, and gas works. The last contributed more to the 8o offensive condition of the river than any other single estabHsh- ment. Taking into account all the data, it was estimated that the manufacturing wastes of the city added 25 per cent, to the volume of sewage to be treated and that the material added in this way was, on the whole, considerably more difficult to deal with than the house sewage. In fact, Mr. Hazen estimated that the difficulty and expense of treating the sewage of the city of Paterson would be increased about 50 per cent, because of the manufacturing wastes of various kinds which the sewers must contain. 2. CONDITION OF THE SEWERS (a) Capacity and Repair. — At the time the report was made there were over 70 miles of sewers in Paterson. Most of these were sufficient to carry away the storm water; a few were much larger than was necessary and some were too small. The sewers were not regularly cleaned or inspected. In fact, some could not be inspected for the reason that the manhole covers had been built over in improving or paving the streets, and this made the sewers practically inaccessible. (b) Outlets and Deposits. — The slopes of the sewers were irregular and of such nature that deposits of sand and gravel from street washings were likely to occur therein. Many of the sewer outlets were submerged by high water in the Passaic river and some by the water of the river at ordinary levels. Investigation showed that many of the sewers were filled to a considerable depth with deposits and that their carrying ca- pacity was thereby considerably reduced. 3. EFFECT OF DIVERTING WATER FROM THE PASSAIC (a) Extent of the Draught. — At the time of the report a part of the water which would naturally flow in the Passaic river was being diverted further up stream for drinking water supplies. The minimum flow of the river w^as reduced about 45 per cent, by this draught. The ordinary flow was reduced by a much smaller percentage. 8i It was thought by some that these diversions of water were chiefly responsible for the objectionable condition of the river, but the author considered that the increase in polluting matter discharged into the Passaic was the main cause. 4. CONCLUSIONS (a) Health Considerations.— Tht author described the Passaic river as dirty and said that the comfort and conveni- ence of residents along the banks required that it should be clean. Cleaning it was a matter of general comfort rather than of public health. The odors which arose from decom- posing sewage did not cause typhoid fever, or smallpox, or scarlet fever or any other contagious disease. They might, and often did, reduce the comfort and happiness and, consequently, in a sense, the health of the people subjected to them, but it could not be maintained that they caused serious sickness. (b) Injury to Property. — The condition of the river v/as such that it was not pleasant to bathe in it or to use it for boating purposes or to live near its banks, and the feeling that it was unhealthful, even though not supported by scientific evidence, had weight with those who had to do with it. The polluted condition of the stream reduced the availability and value of the shore for many purposes, and for these reasons it was w^orth while to clean the river, without reference to public health. (c) Reconiuiendation. — The author recommended that Paterson join with other municipalities in the construction of a trunk sewer to take the sewage of Paterson and of the entire district requiring sewerage in the lower Passaic river valley to a point of sea water dilution. He considered that adequate dilution could be obtained either in New York bay or in New- ark bav near the Kill van Kull. 82 B. Discussion of the Chemical Composition of Pater- son Sewage by Mr. Whipple'-' In his investigation of the composition of Paterson sewage the author approached his problem in two ways. First, he made calculations from such general data as were obtainable from technical text books, modifying this information by what he could learn of the nature of the substances being discharged from the various manufacturing establishments, and, second, he made analyses of the sewage of the city, samples being col- lected at the mouths of the sewers and at various points in the Passaic river above and below the city. I. the house sewage and factory wastes produced by PATERSON (a) Quantity of House Sezuage. — The quantity of water used by the city of Paterson was taken to be approximately 75 gallons per capita. About 89 per cent, of the population was provided with sewer connections. The consumption of water varied according to season, being considerably greater in winter than in summer. The average consumption for the entire year at the time of this report was about 9,000,000 gal- lons per day. The sewers were of the combined type. (b) Polluting Matters from Manufactories. — In summing up the results of his calculations the author estimated that the silk industries of Paterson contributed about 37,000 pounds of solid matter to the river each day. The suspended solids amounted to 16,500 pounds. There were 22,000 pounds of organic matter and 8,000 pounds of fat. The suspended mat- ter was of such character as readily to settle if all the dye wastes were mixed together. The precipitation was aided by the reaction of the iron and tannin. This was proved in a practical manner by the heavy black deposits which covered the bed of the Passaic river below the city. The foul ap- * Appendix I., by George C. Whipple, to report of Allen Hazen to the Joint Com- mittee on Sewage Disposal, Paterson, N. T. See the Joint Committee on Sewage Dis- posal of the City of Paterson. Printed by the Chronicle Print, Paterson, 1906, PP- 3,-3 5- 83 pearance of the river below the city of Paterson was due more to the black deposits on the bottom than to the color of the water itself. It was a continual surprise to those who collected the river samples to note how comparatively free of color the water was in bottles, for in the river it was dark and offensive. (c) Experiments uitli Dye House Wastes. — Some experi- ments were made to determine the effect which the coloring matter from the dye houses would have upon the sewage, sup- posing the sewage to be collected at some central point for purification and no dye wastes allowed to flow into the river. The experiments indicated that the efiluent from the purification plant would have but little color, although there would be at all times a noticeable brown hue and occasionally a faint purple. There was no reason to believe that the trade wastes w'ould interfere with the bio-chemical reactions which would have to take place in the different processes of puri- fying the sewage. (d) Brezvery Wastes. — The methods of brewing employed at Paterson were studied in order to obtain a knowledge of the wastes connected with this industry. The total amount of water used for washing, refrigerating and similar purposes w'as estimated at about 20 gallons for each gallon of beer or ale produced, and 767 barrels w^ere produced per day. For each gallon of beer there were required 2 gallons of water for washing barrels, cleaning tubs and other receptacles, 5 gallons for refrigeration and 13 gallons for various operations connected with the malting process, including the water used for W'ashing floors, tanks and apparatus. It was estimated that the total amount of water used by the brewers of Paterson would be, in round numbers, 450,000 gallons per day. The amount of organic matter put into the Paterson sewers from the breweries was about 150 pounds per day, of which 25 pounds was nitrogen. Inasmuch as no samples could be ob- tained from w^hich to gain knowledge of the malting process, it was quite likely that this figure was too low; in fact, the author thought perhaps it should be doubled. 84 The wastes contained considerable quantities of yeast and reached the sewers in a fermented condition. Considered as a whole, the amount of organic matter from the breweries was very small when compared with that from the silk dye works. 2. RESULTS OF ANALYSES (a) Analyses of Sewage. — On April 18-20, 1906, samples of sewage were collected from the mouths of the principal sewers in Paterson and at the same time gaugings were made of the flow of sewage. From the analyses of these samples and data as to the volume of sewage it was possible to calculate the number of pounds per day of sewage matters discharged by the city sewers. Sixteen sewers were examined, representing about 85 per cent, of the total volume of sewage produced by the city. The results of the analyses were calculated as so many grams of ingredient per capita per day. The data of principal interest follow : Total solids 360 grams Organic matter 189 Mineral matter 171 Suspended solids 69 Chlorine 29 " Nitrogen 13 " Albuminoid ammonia 2.5 Free ammonia 5-^ Fat 63 " The foregoing figures do not include the wastes discharged from all the factories ; many factory drains discharged directly into the river. The effect of the silk dye house wastes was evi- dent in the large amount of fat. In 5 out of the 16 sewers these dye wastes conspicuously colored the sewage. (b) Analyses of River Water. — In order to ascertain the amount of sewage and trade wastes discharged by the city into the Passaic river three series of samples were collected from the river on January 19 and 20, February 17, 18 and 19 and 85 on June 12, 1906. The quantity of water flowing in the Pas- saic was determined at the same time. The first series was taken near Passaic falls, above which the city contributes Httle or no sewage to the river ; the second at a point below all important sources of pollution from the mills, and the third at a point below all city sewers. The samples at all places were collected hourly for 24 hours. Each sample was a composite of three portions, one taken at each side of the river and one at the centre. Each hourly sample was analyzed separately for turbidity, color, odor, chlorine and alkalinity. The samples were then combined to make a representative sample for the day. These composite samples were subjected to full sanitary chemical analyses. (c) First Series of Analyses. — The first series of analyses showed great differences between the day flow and night flow of the river. Thus, the turbidity at the point below the inflow of most of the manufacturing wastes varied from 7 during the night to 48 during the day. The average was 14 for the night and 35 for the day. Similar differences were noted in regard to chlorine and alkalinity. During the night the color of the water was substantially the same above and below the city, but during the day nearly all the samples collected below the city had a bluish or reddish color, due to the discharge of dye wastes into the river. All samples taken from the river below the gas works possessed a tarry odor, due to the discharge of waste material from the gas works. The intensity of this odor varied at dif- ferent times during the day and night, showing that the dis- charge was intermittent. In the samples collected on Sunday there was a smaller difference between the day and night results. At the points where the turbidity had varied as just described, the turbidity of the water during the day was 10 and during the night 8, while the colors were 21 and 16, respectively. The wastes discharged from the gas works were apparently less in amount, for only a few Sunday samples possessed tarry odors. Samples collected below the city on Sunday and Monday showed the 86 effect of the trade wastes discharged on Saturday. All these samples were more or less colored with dye wastes and pos- sessed tarry odors. The samples collected in the third series on June 12 showed that somewhat less polluting matter was being discharged into the river than at the time the first series was collected. This was due, to a considerable extent, to smaller amounts of waste material from the gas works. From the foregoing studies calculations were made to show the total amount of polluting matter discharged into the stream. Considered as a whole, the data obtained on the dif- ferent days were somewhat conflicting, but in the main they substantially, corroborated the figures already given for the amount of nitrogen, fat and other ingredients. Referring to the results of analyses of hourly samples from the Passaic river above and below Paterson in the first series on January 19 and 20, 1906, it is noticeable that w^hen the discharge of the stream varied from about 1,300 cubic feet per second to about 1,650 cubic feet per second, the average turbidity for the entire period of 24 hours w^as 6.5 above Paterson, 25 at Paterson and 7.5 below Paterson. The color was 32, 36 and 33 at the three points, respectively. At the three points named the odor was described as 0.25 disagree- able, 2.5 tarry and 2 tarry. Chlorine was 2.75, 6.3 and 6, re- spectively. The alkalinity w'as 22, 26 and 25, respectively. Turning now to the results of complete analyses of the six hourly samples from the Passaic river above, at and below Paterson, collected in the first series, the following results were obtained. The total solid matter was 74.5, 114 and 106.5; the suspended matter was 3.5, 22.5 and 3.0; the free ammonia was 0.024. 0.080 and 0.160; the albuminoid ammonia was 0.133, 0.480 and 0.260. (d) Second Series of Analyses. — In the second series of samples the Passaic river was discharging 421 cubic feet per second. Averages of hourly samples collected at the points already named gave the following average results : Turbidity. 5, 9, II ; color, 16, 18.5, 3.C) grey brown: odor, o, 5 tarry +0.6 disagreeable, 1.25 tarry; chlorine 3.5, 5.25, 7.25. 87 The average results of the complete chemical analyses of mixed hourly samples from the Passaic river, collected in the second series, included the following figures for the three points referred to: Total residue above Paterson, 97; at Paterson, 96; below^ Paterson, 121; suspended solids, 4, 15.5 and 15, respectively; nitrogen as free ammonia, 0.022, 0.175 and 0.150; nitrogen as albuminoid ammonia, 0.197, 0.485 and 0.505. (e) Third Series of Analyses. — Referring now to the third series of analyses the turbidity in the hourly samples ranged from about 12 to 15 at Passaic falls and from 16 to 35 at Nineteenth street bridge. The color above Paterson was about 34; at Paterson it was slightly yellow and slightly purple, reddish yellow and reddish purple. The odor above Paterson was described as i vegetable and at Paterson from i disagreeable to 3 disagreeable. The chlorine above Paterson was 4 and at Paterson from 7 to 12. Referring to the complete analyses of the 6 samples from the Passaic river collected in the third series, it is noticeable that the total residue was 79 above Paterson and 134 at Pater- son; the suspended solids at these two points were 5.0 and 21.0, respectively. The free ammonia was 0.050 above Paterson and 0.890 at Paterson; the albuminoid ammonia was 0.220 above Paterson and 0.640 at Paterson. It remains to summarize the results of analyses of the sewage made at the 16 sewer outfalls. The total solids of the sewage of Paterson varied from 363 to 2,755 parts per million. This was equivalent to 87,200 pounds per day for the entire city of Paterson. The suspended matter in the sewage varied from 45 parts to 641 parts per million. This was equivalent to 16,650 pounds for the entire city per day. The free am- monia varied from 4.10 to 45.0 parts per million. This was 1,400 pounds per day for the city. The albuminoid ammonia varied from 2.10 to 9.90 parts. This was 600 pounds per day for the entire city. LB N 10