14 Stor m and Surface Water Dr ainage Management In this chapter you will learn about: •
The wide variety of options for a designer to manage storm water
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How storm water management can serve multiple uses
Introduction Approximately 70 percent of the earth’s surface is covered by water, and over 96 percent of this water is saline, found in the oceans. The remaining 4 percent of this water, found on the land, is in the form of lakes, rivers, glaciers and ice fields, and wetlands. Water also exists in the earth’s atmosphere in the form of water vapor. The water vapor is one part of a cyclic system called the water cycle, whereby water vapor condenses in the form of rain or snow to fall to the ground, then disperses across the Earth’s surface to either infiltrate into the ground or travel across the ground as water runoff. Water that infiltrates into the Figure€14.1╇ Neighborhood street scene reflection in one ground saturates the soil, is taken of the urban canals in Delft, the Netherlands
