The hydraulic behaviour of the city of Winnipeg : standard, storm water, sump inlets
Brandson, Norman B.
Contrary to common belief, the rapid removal of storm water runoff from urban areas by the use of man-made storm drains, is not at all a recent innovation. All early Roman cities were equipped with elaborate storm drainage systems, some consisting simply of open channels along roadways, but many of subsurface conduits with attendant inlets. Some of these early urban storm water drainage facilities, dating from before the birth of Christ, are still in existence today. It is due to the fact that urban storm drainage was constructed centuries before any thought was given to the disposal of sewage from a city's concentrated populace, that we owe the existence of the combined sewer, a pestiferous device handling both raw sewage and storm runoff. When sewage disposal was finally undertaken in the nineteenth century, the objectionable material was simple dumped into the existing storm drains. There have been two basic reasons which have moved people to construct storm runoff facilities in urban areas. The first is one of concern for the safety of life and property, that is the prevention of major flooding in the cities. (This is less of a concern on the Canadian prairies, however, as the most serious flooding is caused by spring snowmelt.) The second is more a consideration of convenience, where storm drainage is installed so that the movement of people and vehicles will not be hampered by the presence of large amounts of water on the city's thoroughfares. In North American cities, well into the third decade of the present century, the design of urban drainage facilities was rather a haphazard procedure, depending almost entirely on the personal experience of a particular municipal engineer, rather than on any rigorous scientific approach. The three major tools of today's urban hydrologist, statistics, fluid mechanics and economics, were seldom applied. Early in the nineteen-thirtys, chiefly in the large cities of the American Eastern seaboard, a much more scientific and rational approach to the design of urban storm drainage systems began to emerge. The "rule of thumb methods" were being brought into serious question...