Water is defined in terms of its chemical composition and dominant physical properties, such as expansion on freezing and high surface tension. Water on the earth is about 97 percent in the seas, 2 percent in glacier ice, principally Greenland and Antarctica. Man is left with less than 1 percent as liquid fresh water to sustain his needs. This is possible under good management because water moves cyclically. Conjunctive use of surface and ground water is advocated, as is reuse of wastewater. Water needs for domestic and light industrial use can be reasonably forecast for planning purposes. Heavy-industry needs must be determined on a site-by-site basis.
The units commonly used by hydrologists with respect to quantities and quality of water are denned; their significance in water management is outlined, and metric-english equivalents are given for many. A glossary of terms concludes the report which is intended as a reference work for use by planners and managers.