Encyclopedia of Environmental Science and Engineering, Volume I and II

342 ENVIRONMENTAL HEALTH

Ground-water supply to lakes, streams, oceans

Percolation

Ground-water storage

Rock

Soil

Ground-water discharge

Supply to vegetation

Dug

well

Driven well

Clay

Surface runoff

Spring

River, lake,

ocean

Evaporation from

water surfaces

(Warm air)

Transpiration from

vegetation

Evaporation from soil and surfaces

Evaporation from vegetation

Evaporation while falling

Precipitation (cool air)

Rain-sleet-hail-snow-dew

Clouds

Rain clouds

Atmospheric vapors Moisture

in transportation

and in storage

Infiltration

Drilled Well

FIGURE 3 The hydrologic or water cycle. From Joseph A. Salvato, Jr., Environmental Engineering and Sanitation, John Wiley

& Sons, Inc., New York, NY, 1972.

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