Chapter 5 of The Water Works of the City of Philadelphia: The Story of their Development and Engineering Specifications
Compiled in 1931 by Walter A. Graf (Staff Engineer, The Budd Company, Philadelphia), with the assistance of Sidney H. Vought and Clarence E. Robson. This online version was created from an original volume at the Historical Society of Pennsylvania, Catalog No. WZ 23591 (4th Fl. Folio).
Walter Graf History Home Page
(With Notes on the Text, Preface, and Acknowledgements)
Reading the Preface will give a quick overview of the beginnings and expansion of the Philadelphia water system.
THE EIGHT BREAST WHEELS and one water turbine wheel in the Fairmount Water Works operated very successfully. However, except for about 10 days in each year a large amount of surplus water flowed over the dam thus wasting water and waterpower while the city was constantly growing, and additional water supply became increasingly necessary as the years passed. During 1859 the water pumped by all the city’s stations then in operation, namely Fairmount, Schuylkill, Delaware, and Twenty-fourth Ward, averaged 19,638,442 gallons a day. The consumption in the city during the summer months ran as high as 25,633,395 gallons a day.
After considerable study it was decided that the power of the Fairmount Works should be increased to take advantage of the mean capacity of the Schuylkill River. The first plan that suggested itself was to remove the old breast wheels and substitute wheels of a more modern type and larger capacity and better adapted to the peculiarities of the location. This suggestion was impossible of attainment because the entire capacity of all the wheels in the old works was required to maintain the supply and not one of them could be shut down for the considerable period required for its replacement. Indeed, the old works, with its eight breast wheels and one turbine, was worked to its full capacity most of the time and with but little time taken for repairs or alterations of any kind. Fortunately, no serious consequences of continuous wear and tear had been encountered.
In addition to this there was the danger and difficulty that would attend the blasting of the rock upon which the old portion of the mill houses were built in order to procure a sufficient depth to utilize the entire volume of river water at low tide. The head arches through which the water from behind the dam entered the forebays would not allow free passage of a sufficient amount of water to furnish the proposed increase of power. These arches could not be enlarged without stopping the entire Fairmount Works. Therefore, it was decided to erect an additional mill house on a portion of the site of the mound dam in which three additional water turbine wheels of the Jonval type could be installed. The first Jonval Turbine erected in 1851 had given continuous and excellent service. This additional capacity was expected to more than double the capacity of the old works and to save at least $20,000 a year in the operation of the Water Supply System by permitting some or all of the steam plants then used to remain idle during the season when the consumption of water was at its lowest, for during that same season the Schuylkill water available for power was most plentiful. This arrangement did not include stopping the Twenty-fourth Ward Works, which was the only source of supply existing for the district west of the river.
Work on the additional unit was started in the summer of 1859. The unit was completed and set in operation in 1862. The unit is shown in plan in FIGURE 17, top left.
The new mill house was of substantial construction. Little wood was used. An elliptical wrought iron flume having a sectional area of 70 square feet conducted the water from the inlet at the head arches to each wheel. The wheels were much larger than the wheel of Fairmount’s first Jonval wheel and embodied improvements which had been developed since the installation of the first one. They were rated at 125 horsepower each. Each wheel drove two pumps 18 inches in diameter with a 72 inch stroke. Power was transmitted from the turbine wheels to the pumps through bevel gears between the vertical shaft of the turbine and a horizontal countershaft, and through a pair of spur wheels between the countershaft and the crank shaft of the pumps. The pinions of both pairs of gears were of iron with the teeth accurately dressed while the mortice wheels were provided with hickory teeth. The crank pins of each pair of pumps were set at 90 degrees to each other. The mean rated capacity of all six pumps was 16 million gallons a day, with a maximum of 18 million gallons. The maximum was exceeded on August 21, 1866 when 21,380,300 gallons were pumped by the three new wheels and their six pumps.
The water from these new pumps was conveyed to a new standpipe 60 inches in diameter and 64 feet in height. It was built of wrought iron and enclosed in stonework. The old standpipe was connected with the new one by a 36-inch diameter pipe extended from the new standpipe seven feet below its top, and this connecting pipe was enclosed with stonework in the form of an arch.
The large capacity and successful operation of the four water turbines installed at this station (the initial one in the old Fairmount steam works engine house and the three new ones) encouraged the water works management to recommend the substitution of water turbine wheels for all the breast wheels. This substitution called for rebuilding and enlarging the old wheelhouse. This plan was carried to completion beginning in 1868 and concluding in 1871.
The first of these replacement turbines started operating on February 17, 1869. [Source: Annual Report of the Chief Engineer of the Water Department of the City of Philadelphia, presented to Councils February 10, 1870. Philadelphia: E. C. Marley & Son, 1870, p. 5]. It replaced two of the old breast wheels. This turbine was the largest in the works as well as the largest in the country, being 10 feet three inches in diameter and 17 inches deep in the bucket. It drove two double acting force pumps of 22-inch diameter and 72-inch stroke.
During the summer of 1869 a drought of such unusual duration and severity occurred that the station capacity was temporarily supplemented by two steam pumps obtained from a wrecking steamer. These pumps were erected north of the forebay (see FIGURE 17 for the location) and used until the freshet of October 4, 1869, when water eleven feet nine inches deep flowed over the dam.
The installations of the second and third turbines in the old wheelhouse were completed and they were respectively started in operation on June 20, 1870, and December 14, 1871, thereby completing the replacement of six of the old breast wheels. This left but two of the old wheels, one in each end of the house. One of these two was still useable but the other was not. Its replacement by a turbine was recommended. but the recommendation was not followed. Both of the two remaining breast wheels were eventually discarded, but new equipment was not put in their place.
Thus in the Fairmount Works for many years 13 pumps were operated by seven water turbines. Six turbines (Nos. 3, 4, 5, 7, 8 and 9) each ran two pumps; one turbine (No. 1 in basement of the old Fairmount steam engine house) ran one pump. Their nominal capacity was 33.29 million gallons a day figured on pump piston displacement.
FIGURE 17 is a plan and FIGURE 18 is a photograph of the completed plant. FIGURE 19 contains a plan and a section of the old and new dams.
The turbine started December 14, 1871 was the last installation of improved equipment in this station. During the several years immediately following 1879 the runners of all the turbines were replaced by a new type, a runner known as the duplex wheel, which was credited with increasing their efficiency approximately 40 percent. These improvements were made under a contract with Emile Geyelin, the engineer who designed the first and installed all the later turbine wheels at Fairmount. In time, however, the city outgrew even this capacity increase.
In 1885, the Water Bureau admitted that the Fairmount Water Works could not be depended upon during the times of greatest need. This water powered station gradually lost prestige and steam powered stations attained ascendancy in Philadelphia. One by one as the city added other pumping stations and added to their capacity, steam power was adopted for them.
The publishing of the pumpage diagrams of 1875 in comparison with similar diagrams for 1895, disclosed some interesting facts. In 1875 the main dependence of the city was upon the turbine wheels at Fairmount, and the steam driven pumps at the Spring Garden and other stations (east of the Schuylkill) were used but as auxiliaries during the summer months, when the reduction of the river flow and the increase consumption rendered it difficult for the turbines to keep pace with the demand. In 1895 conditions were entirely reversed. The Spring Garden Steam Powered Station in 1895 pumped more water than all the other stations combined. Further the records showed that the city’s total nominal steam-powered pumpage capacity in 1895 amounted to 347 million gallons daily, while the nominal water-powered pumpage capacity was 33 million gallons or only 9.5 percent of the steam-powered capacity. The availability of the great pool of water back of the Fairmount dam, which was drawn upon by the steam powered stations to supply the city, came to be of more importance than the availability of waterpower for driving the Fairmount pumps. The importance of this pool was stressed by the statement that it was of such immediate and vital consequence that failure of the Fairmount dam would involve the draining of the Fairmount pool, and leave eighty-four percent of the city pumpage system at this date (1895) without water and would put the pumping stations at Fairmount, Spring Garden, Belmont and the new Queen Lane station all out of commission.
During 1897, while extensive repairs and rebuilding were in progress on the Fairmount reservoirs, wheels No. 1 and No. 3 were out of commission. They pumped into the Fairmount reservoirs only whereas the other five wheels pumped into either the Fairmount reservoir or the Corinthian reservoir.
By 1902, only 6½ percent of the total pumpage of the stations was by waterpower, and that large part of the total Schuylkill River supply which was used to accomplish this small service was beginning to assume considerable importance. It was computed that 30 gallons of water were used to run the turbines for every gallon pumped into the reservoirs. During 1904, 1905, and 1906, $25,000 was spent on repairs to the dam.
In these declining years of the Fairmount pumping station, there were some notable instances of renewed activity. For example, in 1905 this station supplied over seven billion gallons, or an increase of more than 66 million gallons over the previous year. From this time on, however, the activities of this station rapidly diminished, and by 1909 the works were about shut down. It was officially announced on February 18, 1909, that the water supply formerly obtained from this source would now be obtained from the new Lardner’s Point pumping station on the Delaware River. Nevertheless, the older station was used for the balance of the year to keep the Fairmount Reservoirs filled and to supply one large manufacturing establishment in the city. During 1910 the No. 4 wheel and its pumps were run for a short period every month and pumped a total for the year of 180 million gallons. The final pumping at this station was in 1911, when No. 4 wheel ran for 56 hours in January and February and then joined its mates in idleness and discard.
The Fairmount station was turned over to the Department of the Mayor by an ordinance of Councils approved March 16, 1911. The machinery was removed, the buildings were renovated, and Philadelphia’s Aquarium established in them. The Aquarium occupies these same buildings today. The exterior appearances of the old and new wheelhouses and the old Fairmount steam engine house are about the same today (1931) as when first constructed, and all the buildings are in good condition. The complete mechanism comprising the first Jonval Turbine installed in 1851, remained in its original location in the buildings until early 1930, when a large portion of the turbine was removed to allow for the passage of a new sewer. The gearing and pump remain intact and can be seen there at the present time. In the same year [WRONG – not 1930] the Fairmount reservoir site was transferred to the Fairmount Park Commissioners to be used as the site for the Art Museum.
In 1916, the replacement of the dam with a more permanent and substantial structure was recommended. Attention was called to the fact that because it was of rock filled timber crib type of construction it would be an almost constant source of expense for repairs, not to mention the menace of its possible failure. These recommendations were unheeded and in 1918 the apron of the dam was destroyed in the spring breakup of the ice. Repairing the old structure cost the city over $45,000 and efforts for the building of a new dam of masonry or some other more substantial and permanent type were renewed. In 1918, the Belmont and Queen Lane stations were the only stations relying upon the pool created by this dam, and they continue the only ones. Preliminary steps toward the building of a permanent dam were taken in 1921 when test borings were made to obtain the necessary information for the erection of such a structure. Construction of the present permanent dam commenced in 1924 and was completed in 1926.
The storage facilities of the Fairmount waterpower works consisted of four reservoirs which were constructed at different periods as the population grew and as the consumption of water increased. The first was finished in 1815 at a cost of $ 32,508.52. It was 317 feet long, by 167 feet wide, with a depth of 12¼ feet, and had a capacity of 4,779,544 gallons. The second, finished in 1821, cost $9,579.57. This was 316 feet long by 140 feet wide, with a depth of 12¼ feet, and it held 4,021,649 gallons. The third, costing $24,521.75, was completed in 1827. It was 317 feet long by 160 feet wide, with a depth of 12¼ feet and a capacity of 3,302,900 gallons. The fourth reservoir was in three sections; a first section, built in 1835, 350 feet long by 136 feet wide and 12¼ feet deep holding 4,462,780 gallons; and second and third sections completed respectively in 1835 and 1836, which combined were 392 feet long and 358 feet wide with and a depth of 12¼ feet, the second section having a capacity of 5,345,212 gallons, and the third section having a capacity of 4,966,925 gallons. The total cost of the first, second and third sections of reservoir number four, was $67,214.68. The total cost of all the Fairmount reservoirs together was $133,824.42. Their combined capacity was 26,879,010 gallons. The water level in the reservoirs was 94.14 feet above the city datum, 51 feet above the highest, and 91 feet above the lowest regulated curb height in the old city proper.
The Corinthian Avenue reservoir was also supplied from the Fairmount works. This reservoir, (situated between 22nd Street and Corinthian Avenue and Poplar and Parrish Streets), was built during the years 1851 and 1852. It was formed of earth embankments lined with brick and contained when full 20,321,392 gallons, thus affording the Fairmount works an aggregate storage of 47,200,402 gallons. Its water was 110 feet above the city datum, 107 feet above the lowest, and 67 feet above the highest curb regulation of the city proper. This reservoir, being elevated higher than those of Fairmount, was supplied by means of a standpipe 50 feet high and four feet in diameter erected on the river side of Fairmount reservoirs. The mains from the Fairmount station pumps were so arranged that water could be pumped through one or all of them, into either the reservoirs at Fairmount or the standpipe for redistribution to the Corinthian reservoir. From the reservoirs at Fairmount there were three distributing mains, one of 30 inches diameter, one of 22 inches diameter, and one 20 inches diameter and from the standpipe a 30 inch diameter main ran to the Corinthian Avenue reservoir.