MEETING OF THE NEW YORK SECTION OF THE AMERICAN WATER WORKS ASSOCIATION
The first 1915-16 meeting of the New York section of the American Water Works Association was held at the Manhattan Hotel, New York City, on October 20th. Luncheon was served at 12.30, after which the program was taken up. Robert E. Milligan presided in place of J. Waldo Smith, Chief Engineer of the New York Board of Water Supply, who was on the program for a paper. The first feature was a paper by Carl P. Birkenbine of Philadelphia, entitled “Variations in Precipitations As Affecting Water Works Engineers.” Mr. Birkenbine dwelt on the importance of precipitation data both for water supply calculations and also for engineering calculations. He cited instances where it was necessary to allow a considerable portion of time in a contract period for rainy weather. From data compiled by Mr. Birkenbine, he estimated that the minimum rainfall during any season would be about 40 to 60 per cent, of the average rainfall for the season. In April in Philadelphia, the lowest month record for rainfall was made, while in August, the hottest month, the heaviest record was obtained. This was due mostly to thunder storms of one and two hours duration. The minimum year does not naturally include the minimum month of rainfall, for the months throughout the year may have a lower average. Mr Birkenbine’s paper was well illustrated with lantern-slides and proved to be an interesting as well as an educational topic.
Mr. Provost added a little to Mr. Birkenbine’s theme by presenting data which had been obtained since automatic rain gauges were adopted. He also called attention to the fact that the maximum rate of precipitation must necessarily be known in the design of spillways and other similar structures. Mr. Trautwine, of Philadelphia, pointed out the effect of reforestation on rainfall. W. W. Brush, Deputy Engineer of the New York Board of Water Supply, spoke on the effects of precipitation on water storage. In part, he said: “It may be of interest to the members of the association to have pointed out to them the effect of rainfall on water supply, both where it is drawn from a sub-surface and also from surface sources. Long Island has sub-surface supplies while the Croton System has a surface supply. Long Island is previous and little water reaches the ocean. In the case of the Croton supply, most of it runs off. During 1911 and 1912, a very heavy precipitation fell on the two watersheds mentioned above; ten inches in Brooklyn and seven inches in the Croton watershed. The best data to determine the underground supply is from infiltration galleries. Porous pipes are laid and the amount of water filtering in is determined. These galleries are so placed through portions of land that they intercept practically all of the underground flow. From July to October a marked reduction in the flow was noted. At the end of a long drought a change took place on the Croton watershed where we have the surface watershed. We had a run-off of 25,000,000 gallons per day in July and 6,000,000 gallons more in October, but in the period between, a greatly reduced amount. Where you have a watershed like Long Island and the water is flowing at the rate of 30 feet per day, you will have a lower flow because the water flows too quickly and the run-off does not take effect very rapidly. In the case of the the Croton watershed, the increase in quantity is immediately after the fall of rain. An increase in the underground supply is evidenced only after two or three months following the rainy season.”
Francis F. Longley: “Careful records have been kept in the Catskill regions of precipitation. In the keeping of these records the personal factor is very important. However, the performance of the gauges are very satisfactory. Snow is a very important factor in rainfall.”
Mr. Smith then read his paper on “Some Views of the Los Angeles Aqueduct.” The Owens River parallels the main range of the Sierra Nevadas and has its source in and derives its water from these mountains. The snow-fall is extremely heavy in the high eastern side of the Sierras, and nearly every canyon that leads steeply down to the plains of Nevada and the adjoining Inyo and Mono counties, in California, carries fine streams of water throughout the year, which streams are veritable rivers in the spring and summer months when the winter snows are melting. Thirty-five such streams empty into the Owens river from a drainage area of 2,800 square miles. The length of the river is about 150 miles. Its waters are made up altogether of the snow waters from the Sierras. The valley itself is from two or three to ten miles wide, and sufficient water flows in the river to irrigate all this valley, with an overflow into Owens Lake, area 75 square miles, ficient volume to supply a city of two millions of people with an ample quantity for domestic use. It was to this source that Los Angeles turned when it was foreseen that in the course of its rapid growth there might be a shortage in the indispensable water supply. The intake of the Los Angeles aqueduct, which is constructed of concrete in the most solid and substantial manner, is situated thirty-five miles above the mouth of the Owens river, this to insure against the possibility of alkali solutions. Its elevation above sea level is 3,812 feet. The dimensions of the aqueduct vary greatly on different parts of the work, depending upon the physical nature of the country through which the water is passing The first 22 miles is a canal, 62 feet wide at where it performs no useful service, of sufthe water surface, 38 feet wide at the bottom and 10 feet deep, incemented, and at a slightly higher elevation than the river. This canal was excavated by three electric dredges. At the Alabama foot-hills the aqueduct is connected along the mountainside, passing Owens Lake on its western side and about 200 feet above the surface. This part of the aqueduct is concrete lined, 30 feet wide, 12 feet deep and 38 miles long to the Haiwee reservoir, the first of the five great storing basins. This upper portion of the aqueduct, to Haiwee reservoir, is the only portion uncovered. All the remaining conduit is covered with reinforced concrete slabs six inches in thickness. The conduit is lined with concrete from eight to twelve inches in thickness. South of Haiwee reservoir the size and shape of the aqueduct vary considerably, and they were determined by the topography of the country and the character of the soil. The average size is 12 feet wide and 10 feet deep. The enormous amount of tunnel work the great length of the tunnels and the rapidity with which they were driven constitute one of the most notable features of the aqueduct. All told there are 150 tunnels on the line, varying in length from 100 feet to the great Elizabeth tunnel, 26,870 feet, or over five miles long. All worlds records for tunnel construction were broken in this tunnel. The estimate of the Board of Consulting Engineers was that one year’s time would be required for preparation, four years for actual construction and $1,913,000 to cover the cost. Work was commenced simultaneously at both ends of the tunnel, October 5, 1907, and 250 men were employed night and day in boring the mountain. An average rate of 11 ins. per hour was made throughout, and the tunnel was completed February 28, 1911, in a period of 3 years and 7.3 months and at a cost of $500,000 less than the estimate. It is the second longest water tunnel in the United States. The total length of tunnels on the aqueduct is 52,035 miles, of which 42,903 miles is on the main aqueduct, and 8,906 miles on the power system.
Herewith are illustrations; the first showing excavating canal section of the aqueduct. Both the bucket and suction types of dredges were used, but the latter being the more successful, two of these were employed during the construction of the entire canal section. Across a small gulch and where the thin steel siphon pipe would not be rigid enough to support the weight of water, concrete flumes were constructed. Concrete for canal, and, in fact, all similar work was made at a concrete plant purchased and operated by the city. The steel siphons were constructed of steel sheets from 5-16 to ⅜ inches in thickness. The cut and cover conduits were built as shown in the accompanying picture.
Los Angeles has a variation per capita consumption ranging from 150 in some months to 300 gallons per capita in other months.
Mr. Smith’s paper was highly appreciated both because of its completeness and the interesting pictures which he brought out. Mr. Kimball, superintendent of the New Rochelle Water Co., spoke on the State Board of Health rules relative to pollution of water and the hardships which they imposed upon the various water companies who tried to enforce non-pollution of watershed measures.
Those in attendance were, L. P. Anderson, Anderson & White, New York; V. E. Arnold, District Manager, Pittsburgh Meter Co.; M. N. Baker, Morristown, N. J.; E. S. Bates, Rcnselaer Valve Co., Troy, N. Y.; C. R. Bettes, Supt. Far Rockaway Water Co., Far Rockaway, N. Y.; C. P. Birkenbine, Philadelphia; Albert M. Brosius; J. T. B. Bowles; W. W. Brush, Board of Water Supply, New York; J. A. Caldwell, President, Ludlow Valve Mfg. Co., Troy, N. Y.; D. Case, Pitometer Co., New York; W. S. Cetti, Thomson Meter Co., Brooklyn, N. Y.; L. B. Cleveland, E. E. Cole Pitometer Co., R. W. Conrow; J. H. Cook; A. W. Cuddeback, Supt., Passaic Water Co., Paterson, N. J.; T. C. Culyer; J. M. Diven, Supt., Troy, N. Y.; J M. Diven, Jr., Water Dept., Troy, N. Y.; Thomas Duggan; S. N. Durian; Wm. R. Edwards; H. M. Fleming, H. Mueller Mfg, Co., New York; D. W. French, Supt., Hackensack Water Co.; G. W. Fuller, Consulting Engineer, New York; W. B. Fuller, Consulting Engineer, New York; C. B. Gilchrist; J. W. Griffin; F. E. Hale, Chief Chemist, New York Board of Water Supply; Edward Henry; Rudolph Hering, Consulting Engineer, New York City; W. C. Hopper; S. D. Higley, Sec. Thomson Meter Co., Brooklyn, N. Y.; Nicholas S. Hill, Jr., Consulting Engineer, New York City; Wm. R. Hill, Consulting Engineer, New York City; B. B. Hodgman, Engineer National Water Main Cleaning Co., New York City; C. L. House; C. Inglee, Mgr. National Water Main Cleaning Co., New York City; Geo. A. Johnson, Consulting Engineer, New York City; F. T, Kemble; J. A. Kienle, Electro Bleaching Gas Company, New York City; A. F. Kiersten; F. C. Kimball; W. I. Klein; John Knickerbacker, President, Eddy Valve Co., Trov, N. A.; Francis F. Longley, Hazen & Whipple, New York City; D. R. McCarthy, Mgr., Neptune Meter Co., New York City; J. R. McClintock; E. G. Manahan; E. E. Miller; R. E. Milligan, President, New York Continental Jew. Filt. Co., New York City; J. H. Morrison; H. F. Peake, Sales Mgr., Meter Dept., Henry R. Worthington, N. Y. C; E. L. Peene, Supt., Yonkers, N. Y.; A. J. Provost, Consulting Engineer, New York; Dr. H. D. Reuse; F. S. Rccke; F. L. Rector; Wm. Reichard; Wm. Ross, Ross Valve Mfg., Co., Troy, N. Y.; Fred Shepperd, FIRE AND WATER ENGINEERING; Wm. C. Sherwood, Hersey Manufacturing Co.; J. Waldo Smith, Chief Engr. Board of Water Supply, New York City; E. K. Sorensen, Asst. Mgr., N. Y., Jewell Filt. Co., N. Y. City; W. E. Spear, N. Y. Board of Water Supply; H P. Stearns; Mr. Stebbins; H. C. Stevens; Mr. Talbot; Mr. Titus, Reisert Co.; C. C. Todd; J. C. Trautwine, Jr., Consulting Engineer, Philadelphia; W. H. Van Winkle and W. H. Van Winkle, Jr., Water Works Equipment Co., New York; J. S. Warde, Jr., Rensselaer Valve Co., Troy, N. Y., and J. Wilcox.