THE CHICAGO WATERWORKS SYSTEM
The greatest problem in its waterworks system that Chicago has to solve is its present water waste through leakage, imperfect plumbing and reckless household usage. To overcome this waste a survey division of the water department was organized two years ago and the result of its work has been to locate a great number of defective service pipes, faucets and concerns using excessive water. During the past year the water survey division has been conducting a systematic investigation and has surveyed approximately to square miles of the older and central portion of the city. This work consisted in laying out the city in districts ranging from 75 to 300 acres, analyzing the water consumption in each, and eliminating the waste and leakage as far as possible, making a total of 25 districts surveyed in this manner. The results of these surveys show that the rate of supply during the night is little less than for the day period, which is indicative of a large waste and leakage. The actual night usage in the districts where house to house inspections were made show that from 46 to 60 gallons per capita is sufficient supply to meet the demands for domestic consumption and in some sections this requirement is as low as 30 gallons per capita. The surveys also showed that there was a high plumbing leakage, due to neglect of owners and tenants in making repairs, which wastes from 35 to 45 per cent, of the supply. In one square mile on the West Side, where the plumbing was inspected and repaired, a total saving of 5,700,000 gallons was made. After the plumbing in the districts was repaired a resurvey was made to determine the amount of night consumption and underground leakage, which showed a waste of 25 to 35 per cent, in the total supply from excessive underground loss of water due to leaks in the street mains and old service pipes. In three districts of an area of 1.17 square miles the underground leakage was found to be 47 1/2 per cent, of the total supply. The work done by the survev division during 1908 was a continuation on a somewhat larger scale of the waste water investigation work in progress for the past two years. These investigations were made in 23 districts, ranging from 75 to 375 acres each, covering a total area of 4,839 acres. The house to house inspections show that of a total of 12,329 places were inspected which showed 8,428 leaking fixtures and 5,905 underground leaks within the premises inspected. The total unmetered measured leakage as shown by the inspectors house to house reports, give a total leakage of 5,106,300 gallons per day. The total metered leakage in this territory amounted to 416,000 gallons per day. The remaining eleven districts show a metered supply before inspection of 7,176,700 gallons per day and the total unmetered supply 24,531,790 gallons per day. In these districts the total saving in supply was 10,000,000 gallons per day. This saving was effected by repairing plumbing and old mains, besides taking out house service pipes not in use.
CRIBS AND TUNNELS.
The extension of intake cribs became necessary an occount of the new pumping stations. The southwest land and lake tunnel system comprises a new intake crib near the present Sixty-eighth street crib, as shown in the illustration. This new crib was sunk in place in 31 feet of water on August 30, 1908, and the setting of granite was completed in December of that year. The tunnel connecting it is 10 miles long ranging from 9 to 14 feet in diameter and it was constructed in three seclions. at a cost of $3,000,000. The construction of this crib with 16 miles of water tunnels was to supply the three new pumping stations, one at 104th street and Stewart avenue, the second at 75th street and Western avenue and the third near 126th street and Yates avenue, each station to have a maximum pumping capacity of 100,000,000 gallons. The tunnel under the lake is 14 ft. in dia. leading from the crib to 73d street and Yates avenue, from there westw-ard, 12 ft. in dia., to 73d and State streets, continuing southward on State street, 9 ft. in dia., to the Roseland pumping station at 104th street and Stewart avenue. A 9-ft. branch is run westward on 73d street, 3.5 miles long to the station at 75th street and Western avenue. A similar branch runs from 73d street and Yates avenue to the station at 126th street and Yates avenue. The tunnels of the southwest land and lake tunnel system are: Section one, with a total length of 22,366 ft. 9-in. in dia; this section is lined throughout with concrete and was completed last spring. Section two consists of 2,123.3 ft. of 9-ft. tunnel, 15,897.3 ft. of 12-ft. tunnel and 857 ft. of 14-ft. tunnel—all of which were completed in November, 1908. The third section includes about 11,013 ft. of 14-ft. tunnel and 1,167 ft. of 14-ft. land tunnel, also a temporary and a permanent crib. There are five old cribs in the system— namely, the Two-mile crib, Lake View crib, Carter H. Harrison crib, Four-mile crib and Sixty-eighth Street crib. These, with the new crib referred to before, will, it is calculated, be sufficient to meet the wants of the city for many years to come.
The city has eight large pumping stations and three auxiliary plants for raising the pressure in outlying districts. The total daily pumpage from 1890 to 1907 increased front 152,372,000 gal. per day to 454.615,000 gal. per day, and the per-capita consumption for this period increased from 126 to 204 gal. per capita. The total average pumpage for the eight large stations during 1908 was 467,000,000 gal. per day. Of this supply 70,000,000 gal. per day, or 15 per cent., was metered water, and nearly 100,000,000 gal. per day, or 85 per cent., was unmetered water supply.
Following is a list of the pumping stations and their equipment:
Fourteenth St.. 3 Allis Ver. Tri.
Fourteenth St., 1 Lake Erie Ver.
Tri. Exp………………….. 30,000,000
Sixty-eighth St.. 4 Gaskill Hor.
Sixty-eighth St., 1 Holly Hor. Comp. 14,000,000 Sixty-eighth St.. 1 Worthington.
Hor. Comp…………….. 12,000,000
Sixty-eighth St.. 1 Snow Hor.
Twenty-second St., 4 Quintard
Ream …………………….. 15,000,000
Chicago Ave., 3 Allis Ver. Trip.
Chicago Ave., 1 Gaskill Dup. Hor.
Springfield Ave.. 3 Worthington
Du. Act. Tri. Exp…………… 20.000,000
Springfield Ave.. 1 Worthington Du.
Act. Tri. Exp………………… 40,000,000
Central Park Ave., 3 Worthington
Du. Act. Tri. Exp…………… 20,000,000
Central Park Ave., 1 Worthington
Du. Act. Trip. Exp………….. 40,000,000
Harrison St.. 2 Allis ver. Tri. Exp., 15,000,000
Lake View. 1 Holly Hor. Comp…. 14,000,000
Lake View, 1 Gaskill Hor. Comp… 13,000,000
Lake View, 1 Gaskill Hor. Comp.. 12,000,000
Lake View, 1 Worthington Hor.
Washington Hgts., 1 Laidlow Dup. 1,500,000
Washington Hgts., 1 Allis-Chalm-
ers Du. Act. ……………… 3,000.000
Norwood Park, 1 Deane Dup…… 170,000
Norwood Park, 1 Deane Dup…… 190,000
Norwood Park. 1 Cook Well…… 350,000
Rogers Park, 1 Deane Hor. Comp. 1,500,000
Rogers Park, 1 Deane Hor. Comp., 1,500,000
Fullerton Ave., 1 H. & E. Brandy
Ver. Cond…………………. 23,000,000
The total pumpage for the year 1908 amounted to 171,204,568,423 gal., exclusive of the water pumped at Rogers Park, Washington Heights and Norwood Park pumping stations. As compared with the pumpage in the year 1907. which was 165,934,823,150 gal., the 1908 pumpage shows an increase of 5,209,745,273 gal. The average head pumped against was 112.51 ft. as against 113.74 ft. in 1907. or a decrease of 1.23 ft. This slight decrease in the average head may be ascribed to the extremely warm and dry summer weather causing a continuous and unusual demand on the water supply for months at a time, and which unexpected demand could not be entirely met owing to the preparing of the new large pumping engines at Central Park Avenue and Springfield Avenue pumping stations for final tests and acceptance. The cost of pumping 1,000,000 gal. 1 ft. high was, in 1908, for fuel 1.68/100 cents as against 1.56/100 cents in 1907. The total cost of operation per unit was 3.84/100 cents in .1908 and 3.76/100 cents in 1907. The slight increase in cost in 1908 over that in 1907 was due wholly to the increased cost of coal per ton.
WORTHINGTON ENGINE TRIAL.
The report of the test made on the 40,000,000-gal. Worthington pumping engine in the Springfield Avenue pumping station states that it is a vertical, duplex, 6 cylinder, triple expansion engine of the high-duty type, having steam cylinders 27 in., 42 in. and 76 in. in din.; two double-acting, outside packed plungers 45 in. in dia., direct connected to the steam piston rods. All pistons and plungers have a common nominal stroke of 60 in. The trial was begun October, 1908, and continued for 24 hours. It showed the total head on pumps of 123.32 ft.; temperature of steam at throttle (F.°) 543.0; total revolutions of engine, 24 hours, 25,605; average revolutions of engine per minute 17.77; average length of stroke 61.487 in.; average piston speed per minute, 181,964 ft; average plunger displacement, per revolution, 1,678.50 gal.; average plunger displacement per 24 hours, 62,978,103 gal.; net horsepower, 930.43; steam used per net delivered horsepower, per hour, 11.30 lb., and duty per 1,000 lb. steam used, 175,165,516 ft. lb. In addition to the above enumerated engines there are four 25,000,000-gal. pumping engines in the Lake View pumping station and four vertical triple expansion, condensing, seifeontained, crank and fly-wheel engines of 25,000,000 gal. daily capacity each in the Roseland station. In the distribution system there were at the close of the year 1908, 2,189 miles of mains, 18,782 valves and 22,696 fire hydrants. The amount of pipe laid during 1908 has not been as large as in some previous years, and yet there was a substantial growth and development in the system. There was laid during the year a total of 49.1 miles of pipe. Deducting from this 13.1 miles of pipe abandoned or taken up, the net increase is 36 miles. In addition, 638 valves of various sizes and 911 fire hydrants were set. Out of the total of 49.1 miles of pipe laid, 48.5 miles, or 98.7 per cent, was 6, 8 and 12 in. in diameter. There was a total of 372,835 services at the end of the year, 10,212 of which were added during the twelve months.
WATER INSPECTION AND METERAGE has saved the city a large sum by stopping leaks and waste. The total saving from the part survey completed will be 13 to 13 million gallons per day and about $100,000 per year. The engineer’s report says: “While good progress is being made in the stoppage of waste water due to faulty plumbing fixtures and other sources, a complete remedy is not obtained when these repairs are made. This work should be followed up by liberal installation of meters, particularly for all large consumers now paying for water by frontage. In the districts where house-to-house inspections were made, the water saved by repairing faulty plumbing fixtures amounted to an average saving of 35 per cent, of the total water supply of the district. After these repairs were made, the water pressures were considerably increased, and in district No. 13 the water pressure was increased about ten pounds by repairing house fixtures. In other districts similar increases in pressure were felt after the house-tohouse inspections and plumbing repairs were completed. The, table herewith shows the results of this inspection both in metered and unmetered districts inspected.
The total metered revenue from these districts was $183,669 and that from frontage rate $139,278. The revenue for metered water was 7 cents per 1,000 gal. and the rate for unmetered water in these districts, before inspection, was $0.0025. From the figures given in the table it is estimated that a complete survey would show that of tiie 204 gal. of water used per capita per day fully 70 or 80 per cent, of the total supply was wasted. Tlie metered rate of water for the city is 7 cents per 1,000 gal. The estimated cost per 1,000 gal. of water pumped, including allowance for sinking fund, depreciation and interest on the net invested capital, assumed at the rate of 3 per cent., is 2.0 cents per 1,000 gal. The city receives less than 2 cents per 1,000 gal. for its unmetered water, which includes the frontage supply, waste and leakage. As the report says, “the installation of a large number of meters would help materially to restrict the useless and willful waste of water common throughout the city. The increase in revenue from this expenditure would insure a large return on the investment.” At the end of the year 1008, 14,724 water meters were in service. It is estimated that free water service is rendered by the city to an amount equal to $1,399,566.03. Of this amount $204,251.09 is made up of water consumed by municipal and charitable institutions. The balance, $1,105,314.34 is based on an estimate of the city engineer for water consumed by public parks, flushing sewers, street cleaning and sprinkling, and track elevation and street improvement work. The total receipts collected during the year 1008 and credited to the water fund amounted to $6,385,667. In this amount is included $1,400,000 received from the sale of water bonds. 171,031 inspections were made, or a total increase of 38,812 inspections over those made in 1907. The report further states that considerable trouble has been caused by the action of electric currents on the water mains and service pipes. The presence of these currents in the ground is due to leakage in the return conductors of the street railway, elevated railroads and other companies having electric conduits and wires. John Ericson, whose portrait is given herewith, is city engineer in charge of waterworks construction and W. J. McCourt, superintendent.