Water Supply of Amsterdam
The waterworks of Amsterdam, Netherlands, are owned and operated by the city. The supply of water is abundant and the quality is considered excellent for both drinking and general purposes. The water comes from 117 artesian wells situated in the sand-dune district about 12 miles west of Amsterdam and about a mile from the sea. Some of these wells are 120 feet deep, and they are distributed over a territory about 7 miles long and 3 miles wide. The water from the wells flows into a series of canals, whence it is pumped into a great reservoir. To place the water supply beyond all reasonable possibility of shortage, the city now oposes to drill 60 additional wells and to increase the pumping stations and other works, at a cost of over $200,000. Plants and fish exist in the great reservoir, and the water taken therefrom is far from pure. From the reservoir the water is conducted through a 48 inch pipe and is pumped to the first filtering system, where, exposed to the air, most of the iron in the water is chemically extracted from it. Then the water sinks through a layer of gravel of varying fineness, to which most of the remaining iron adheres. The water is so treated in 9 different filters, each with a superficial area of over 100 square yards. It then goes to the finer filter, which contains a layer of dune sand a yard thick, under which is a layer of pebbles resting on an asphalt bottom. This filter has a superficial area of about 24,000 square yards. From here the water is pumped through pipes into the pure water reservoir about 3 miles nearer Amsterdam, and thence into the city as required. The 20 to 24-inch pipes used for the past 50 years to conduct the water to Amsterdam are now being replaced by 30-inch pipes. To prevent the pipes between the first reservoir and the pumping station near the filters from being clogged in any way, they are scrubbed out once a week by an apparatus introduced at the reservoir and pushed along by the water pressure to the pumping station, carrying before it all dirt, plants, etc. The average daily consumption of water in Amsterdam is 14,700,000 gallons; about 9,100,000 gallons from the dunes, 800,000 gallons of ordinary well water, and 4,800,000 gallons from the river Vecht. The river water is used for manufacturing and other industrial purposes; or beer brewing, as the dune water does not make good beer; and for household washings, etc. Some residences are piped for both the dune and the river water, but generally new houses are equipped with only dune-water pipes, and in such cases this water is used for all purposes. The total number of subscribers for water is about 45,000, whereof 2,700 are industries of various kinds, the rest being households. There is an average of 13 persons to each subscriber. The average daily per capita consumption of water is about 25 gallons. This consumption, of course, includes water used by industries, for all household purposes, street and garden sprinkling, etc. The total cost of the city waterworks was about $8,442,000. The total annual expenses are about $700,000. The total receipts in 1910 for water and rent of water meters were $823,978, a small increase over 1909. These figures indicate that the waterworks system makes an annual profit of about $120,000. Factories are charged 4 cents, United States currency, per cubic meter (about 250 gallons) of water used. Dwellings and other users pay according to the number of rooms, taps, lavatories. etc.—Consul Frank W. Mahin, Amsterdam, Netherlands.