Water Supply System of the City of Montreal

THOMAS W. LESAGE

Engineer and Superintendent

Water Works, Montreal, Can.

Water Supply System of the City of Montreal

Two in Use, One Municipal and One Privately Owned — Municipal Supply Described — Six Pumping Mains— Distribution System, 497.6 Miles of Piping—85,000 Services

THE following article, written especially for FIRE AND WATER ENGINEERING by Engineer and Superintendent Lesage, will be of special interest at this time to the members of the American Water Works Association, both to those who attended the convention at Montreal and to those who missed this great privilege, giving, as it does, such a clear and concise description of the water system of that city:

The City of Montreal in the Province of Quebec is situated on the south end of the island of the same name, formed by the course of the St. Lawrence River to the south, and the Ottawa River to the north, and has become by its rapid progress one of the most important cities of North America. It is at the head of ocean navigation, its harbor making it the commercial metropolis of Canada.

Founded in 1642, the city underwent many vicissitudes under French domination, and its civic progress really only dates from the beginning of the Nineteenth Century, and chiefly within the last thirty-five years, when the opening of new streets, the improvements to the highways, the erection of imposing public and private edifices, have brought forth a large increase in population and marked prosperity to the city. Montreal, within its administrative limits proper, comprises an area of about 28,400 acres, and contains a population of 694.000. There are in Montreal two water supply systems: The city municipal system supplying the main portion of the city to the extent of about two-thirds of the above population, and a private water company, the Montreal Water & Power Company, supplying about one-third of the population besides two towns on.the outside limits of the city.

First attempt at Water Supply

Montreal’s first attempt at water supply to its citizens was made in 1801, when a company was formed to distribute water to the citizens through wooden pipes from springs in the mountain. About 1815 another company acquired the rights to supply water and established pumping engines at the river front and put up a tank reservoir of 240,000 gallons near the citadel at a height of 97 feet above the river. In 1830 another company acquired the rights, replaced some of the smaller pipes by pipes of 10 inches in diameter, and renewed the steam pumping engines in 1843 to a pumping capacity of 93,000 gallons per hour.

The city became possessor of the water works through purchasing in 1845, for the sum of £50,000. The city enlarged the works, constructing a reservoir of three million gallons capacity on the Coteau Baron (now St. Louis Square), at a height of 130 feet above the river, and extended the piping system so that by the year 1850 there were 19 miles of cast iron pipes and about six miles of lead pipes, and the expenditure had been £30,000 since the acquisition of the works.

Serious Fire Showed Necessity of Improvement

In 1852, after a serious fire had destroyed part of the city showing the inadequacy of the water supply, a report was prepared and submitted by Engineer T. C. Keefer to install the water supply from the head of the Lachine Rapids with an open canal 4 1/2 miles in length, sufficient to supply the water and hydraulic power to pump five million imperial gallons per day to the proposed McTavish Reservoir at an elevation of 204 feet above the river. These works were carried out and put into operation in 1856. The supply had to be supplemented by steam pumps in l868, as the city’s water consumption had outgrown the five millions capacity of the hydraulic pumping supply.

Meantime the project of enlarging the old aqueduct to utilize the power for pumping sufficient water in keeping with the city’s wants came up at various times. Finally, in 1905, estimates were prepared for widening the aqueduct to develop water sufficient to pump fifty million gallons, and to build an intake out from shore and a concrete supply conduit to bring water to the steam pumps whilst the aqueduct was being widened. The works were begun and the concrete conduit put in operation in the fall of 1909, when the aqueduct was emptied and contracts let for its widening.

In 1910 a further change of plans was decided on. This contemplated increasing the dimensions of the aqueduct to afford sufficient water power to supply and pump 100 million gallons per day. This project was put under contract in 1913, but was discontinued in 1916 as unprofitable, owing to war and other conditions, the great increase in water power developments near Montreal having considerably reduced the cost of purchased electric power since the aqueduct widening was first mooted. The supply through the concrete conduit 8 1/2 feet diameter and five miles long brings water by gravity to the main low level pumping station. The steam pumps are eight in number of a total capacity of 108 million imperial gallons per day.

The Present Water Supply System

The force or pumping mains are six in number, viz.; one 36-inch, two 30-inch and three 24inch. These mains lead into the city distribution system and to the low level or main reservoir. This reservoir, situated at the head of the McTavish Street on the slope of the mountain, has a capacity of 37 million imperial gallons, and is at an elevation of 204 feet above the water level of the harbor. The high level system, into which the water is repumped from the low level, has its reservoir at the head of Peel Street at an elevation of 422 feet, and with a capacity of one and three-quarter million imperial gallons. The upper level system still higher serves a restricted area at Cedar Avenue, and is supplied by repumping from the high level. A covered reservoir on the mountain side at an elevation of 550 feet, and with a capacity of 200,000 imperial gallons serves this upper level system.

The city’s distribution system comprises 497.6 miles of pipes of diameters from 4 to 36 inches. Sixty-seven per cent. of the distribution piping is of 8, 10 and 12-inch size. There are 2,930 hydrants, and the pressures vary on these from 70 to 85 pounds in the lower or business portions of the city to 30 pounds in the upper portions of the low level district. In the high level district pressures vary from 110 to 60 pounds according to location.

Meters Only in Special Cases

There are about 85,000 services. There are no meters in general use as the water is paid for out of the water rates, a municipal tax on all householders paid annually, and amounting to six per cent, on assessed rental.

Meters are installed in certain large commercial and manufacturing establishments, such as railways, breweries, printing establishments and textile mills, also hotels, laundries, schools, asylums and houses of industry, as well as on hydraulic apparatus, elevators, pumps, etc., where the wastage of water has to be controlled. There are 1,668 meters in use covering these cases. The meter rate charge for water is $1.15 per 1,000 cubic feet.

The average daily water consumption for the year 1919 eyas 65,046,000 imperial gallons, and the estimated population served by the city’s system was 449,000, thus representing a per capita consumption of 145 imperial gallons.

Water Supply Drawn from River

The water supply is drawn from the river above the Lachine Rapids, some five miles from the pumping station. The intake is 1,200 feet from shore, and the water drawn in is generally from St. Lawrence River origin. However, as the Ottawa River joins the St. Lawrence River at the head of Montreal Island, some eighteen miles above the intake, part of its waters follow the south shore line of the island, inside the intake, and at certain seasons of flood and force of wind varying quantities of Ottawa River water find their way to the intake. The largest percentage of Ottawa water occurs in May, its distinguishing characteristic is its brown color. The percentage of Ottawa water present in the city supply is indicated by the simple test of determining the alkalinity of the mixture in parts calcium carbonate per million.

The general characteristics of the city water supply are as follows:

The average bacterial raw water count during 1916 was 4,600 per c.c. after 96 hours incubation at 20° C. The chlorinated water contained on the average 19 bacteria per c.c. under the same conditions.

Description of Filtration Plant

Montreal Filtration Plant lies south of the pumping station near the lower end of the five-mile water supply conduit. It is of the double filtration type, that is, the water first passes through the prefilters, or roughing filter sand beds, at a normal rate of 115 million imperial gallons per acre per day. Thence it flows by gravity to the final filter beds, where it passes through at a normal rate of about 8 1/2 million imperial gallons per acre per day. Its capacity is 50 million imperial gallons per day, which is only about three-fourths of the present daily water consumption. Measures are being taken to have it enlarged at an early date. Other additions under way to keep pace with the ever-increasing growth of the city water works service are two 30-million gallon electric motor driven pumps already contracted for. There are also being considered, additions to the reservoir capacity, and to the force mains, as also extension of the distributing mains to the outlying portions of the city.

Washington Passes Safety Limit in Water

With the advent of hot weather, the daily consumption of water in Washington, D. C., has increased so greatly that the margin of safety has been reached. Not infrequently, the consumption is from 66,000,000 gallons up, while the safe daily capacity of the single conduit that brings the city’s supply from Great Falls is estimated at not more than 68,000,000. That figure has been exceeded already on several days. Householders have been warned that strictest conservation must be practised or an actual shortage may follow. The situation emphasizes the urgent need for action by congress to construct another conduit. The use of water for washing sidewalks, except by the street department, is prohibited during July, August and September and lawns may be watered only between the hours of 5 and 8 a. m. and the same hours in the afternoon. Government officials will refrain from using water in fountains in the public parks.

Canton Satisfied with Progress on Water Works

The members of the city commission of Canton, Ohio, recently inspected the work under way on the new water works system and expressed themselves as being well satisfied with the progress made. The commission, calls attention to the fact that notwithstanding increased costs of material, labor and machinery, contracts have been let for the entire construction at an advance of only about $15,000 more than the estimated cost of $1,500,000. Work on the 1,000,000 gallon reservoir at the booster station is practically finished and it is believed that this station will be of the greatest advantage in case of a large fire or other emergency. The commission, while inspecting it, was impressed with the conviction that the surrounding land should be made into a playground, which will probably be done. The same plan will be put into execution at the equalization basin, on which work is being pushed. This station will act a safety valve to the system. The new well section is also progressing satisfactorily, notwithstanding serious delays in delivery of material, caused by the railroad troubles, and it is hoped that the work may, after all, be completed this summer. When the plans of the commission are complete, the city will have provided amply, it is thought, for all water needs of the residential districts for years to come.

Water Commission to Study Philadelphia’s Problem

It is announced that Mayor Moore will appoint a commission to deal with the water supply problem of Philadelphia as soon as he returns from the Chicago convention. The commission will be composed of at least three of the leading water supply experts in the country. This step is the result of the recent statement by Carleton E. Davis, chief of the water bureau, that the water supply is likely to be short this summer. The mayor intimated that the investigation will consider three main projects for the extension of the city’s supply, the first being the one favored by Chief Davis, who considers the Delaware River the logical source of supply. The mayor and Chief Davis are agreed on the ultimate provision of a future water supply sufficient for a population of 5,000,000 people. It will multiply the present capacity of the filtration plants, which is fixed at about 300,000,000 gallons a day, and which are now run in excess of that amount. The greatest present consumption sometimes runs as high as 340,000,000 gallons daily, thus depleting the stored supplies in the reservoirs in many parts of the city. The other two plans are a mountain supply drawn from some distant point, such as the Pocono Mountains, and carried here in immense aqueducts in the same manner that New York city gets its water from the Catskill Mountains. The third plan to be placed under investigation is the provision of a semi-mountain supply capable of development in connection with the local rivers. The works, which were commenced about twenty years ago, have had to be supplemented in recent years, and the latest addition is now being made at Queen Lane, so as to increase the capacity of that plant by 50,000,000 gallons daily. Contracts for this have been awarded since Mayor Moore assumed office, and though the work will proceed rapidly, the new facilities will not be available for use until some time next year, probably not until the autumn of 1921.

Property owners in a certain section of Wharton, N. J., were warned by council, not long ago, that they must make all needed water connections before the borough begins the street paving planned for the immediate future.

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