Watershed Protection Indicates external links with no implied endorsement. The highest ground, such as a mountain, hill or ridge, forms the boundary between two watersheds. At these boundaries, rain falling on one side flows toward the low point of one watershed, while rain falling on the other side of the boundary flows toward the low point of a different watershed.
Individual watersheds combine to form larger watersheds, which are sometimes called basins.
The quality of water in a watershed is affected by every source of pollution in that watershed. The watershed protection approach is an integrated, holistic strategy for more effectively restoring and protecting aquatic resources. This approach focuses on hydrologically defined drainage basins, or watersheds, rather than on areas arbitrarily defined by political boundaries. Thus for a given watershed, the approach encompasses not only the water resource, such as a stream, river, lake, estuary or aquifer, but all the land from which water drains to the resource. To protect water resources, it is increasingly important to address the condition of land areas within the watershed because as water drains off the land or leaches to the ground water it carries with it the effects of human activities throughout the watershed.