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Crossing Boundaries

Many rivers and lakes were selected as boundaries between countries or other political units such as states. Examples of boundary rivers include the lower Rio Grande River (shared by the …

Increase supply

Since ancient times people and their governments have taken on large and creative projects to increase their local water supply. Ancient farmers in the Middle East conceived a way to …

Earth’s water

Earth is a water planet. Seventy percent of its surface is covered by water. Water seems to be everywhere, in the oceans, lakes, streams, glaciers, and even in people. Our …