Water-supply Paper, Issues 397-399U.S. Government Printing Office, 1916 - Floods |
Other editions - View all
Common terms and phrases
12 inches 24 Bored 68 Hand 68 Wind acres of alfalfa alfalfa alkali amount Artesian average base and meridian basin belt-connected boiler Bros calcium carbonate catalogue capacity cent chloride complete plant County-Continued deposits diameter Depth distillate engine drainage drilled Electric estimated or statement feet deep flow Fresno County gallons per minute ground waters horizontal centrifugal pump Horse horsepower irrigation Kern County Kings River magnesium Merced Method of lift miles Miner's inches mineral content Mount Diablo base Naugatuck River operation owner taken pera pipe pleted pulley pumping plants radicle reservoir results were obtained revolutions per minute rock San Joaquin County San Joaquin River San Joaquin Valley sand shallow Slope sodium Southern Pacific Co statement of owner Stockton streams suction sulphate surface waters Test.-The following results Total static head Tulare Lake ture of water Type and diameter Water pumped water supply west-side
Popular passages
Page 98 - Removal of bacteria, especially those causing disease, and removal of turbidity, odor, taste, and iron are the principal requirements in purification of a municipal supply, elimination of bacteria and suspended matter being the most important. The common methods of effecting such purification arc slow filtration through sand and rapid filtration after coagulation, both methods usually being combined with sedimentation. The first process is known as slow sand filtration and the second as mechanical...
Page 101 - ... and about half an inch of sand is removed, after which filtration is resumed. The sand thus taken off is washed to free it from the collected impurities and is replaced on the beds after they have been reduced about a foot in thickness by successive scrapings.
Page 79 - FOAMING. Foaming is the formation of masses of bubbles on the surface of the water in the boiler and in the steam space above the water, and it is intimately connected with priming, which is the passage from the boiler of water mixed with steam.
Page 91 - Many open dug wells and many pits constructed as reservoirs around the tops of casings are exposed to fecal contamination from above or through cracks in poorly built side walls. Care should be taken that the casings of deep wells do not become leaky near the surface of the ground so as to allow pollution to enter. As a matter of ordinary precaution the ground should be kept clean and water should not be allowed to become foul or stagnant near any well, no matter how deep. If shallow dug wells are...
Page 90 - ... to guard supplies against all chances of infection. The disease germs most commonly carried by water are those of typhoid fever. The bacilli enter the supply from some spot infected by the discharges of a person sick with this disease and though...
Page 81 - Gary's second class of boiler compounds comprises those that act mechanically on the precipitated crystals of scale-making matter soon after they are formed, surrounding them and robbing them of their cement-like action. Glutinous, starchy, and oily substances belong to this class, but they are not now used to any considerable extent, because they thicken and foul the water more than they prevent the formation of hard scale. The third class comprises...
Page 102 - Softening. The principal objects of water softening are to remove the substances that cause incrustations in boilers, particularly calcium and magnesium, and to neutralize those that cause corrosion. Chemicals of known strength properly dissolved in water are added to the raw supply in such proportion as to precipitate all the dissolved constituents that can be economically removed by such treatment. The water is then allowed to stand long enough to permit the precipitate to settle, after which the...
Page 102 - The water softeners on the market differ from one another chiefly in the precipitant, in the filtering medium if one is used, and in the mechanism regulating the incorporation of the chemicals with the water. Installations may be of any size to suit consumption, and the process can be combined with rapid sand filtration for purifying municipal supplies.
Page 102 - While the raw water is entering the sedimentation basin, which is smaller than that used with slow sand filters, it is treated with a definite proportion of some coagulant, which forms by its decomposition a gelatinous precipitate that unites and incloses the suspended material, including the bacteria, and absorbs the organic coloring matter. This combined action destroys color and makes suspended particles larger and therefore more readily removable. When aluminum sulphate, the coagulant most commonly...
Page 101 - York, 1909, p. 83. of concrete, perforated tiles or pipes laid in the form of a grid are covered with a foot of gravel graded in size from bottom to top, and a layer of fine sand 3 to 4 feet in depth is put over the gravel, which serves only to support the sand. When water is applied on the surface it. passes through the sand and the gravel, and flows away through the underdrain. The suspended materials...