Wady
See Arroyo.

Wash
A shallow streambed with steep sides cut into unconsolidated sediments. This kind of streambed usually carries water only after brief, local precipitation.

Waterglyph
Rock art images of a specific circle and line form that are carved into a horizontal surface near the edge of a cliff and appear to be pointing toward a source of water at some point in the distance.

Water Pocket
A bowl in rock that has been formed by the erosional action of falling or running water. Often times a collection point for rain and run off water, and thus a potential source of drinking water for wild animals and humans. See also Tank, Tinaja, and Pothole.

Watershed
A watershed is defined as that geographical or geological area that is drained by one river system. For example, if a drop of rain lands near a ridge line, it will eventually run off, or flow, to the stream at the canyon bottom. All surface and ground water which contributes to a stream would be part of that watershed. Regulations governing the use of these areas protect all the sources of water that contribute to the stream system or watershed.

Water Table
The upper limit of the portion of the ground wholly saturated with water.

Wetland
A general term for a group of we habitats. It includes areas that are permanently wet or intermittently covered by water.

Widowmaker
A burned tree, or one with a decayed trunk or roots or snagged limbs, that may fall without warning.

Wilderness
A tract or region uncultivated and uninhabited by human beings, essentially undisturbed by human activity, together with its naturally developed life community, generally an empty pathless area. The Wilderness Act of 1964 defines wilderness as an area "where the earth and its community of life are untrammeled by man."

Wildland Fire
A wildland fire is a non-structure fire, other than a prescribed fire, that occurs in the wildland. These fires can potentially damage or improve park resources. Wildland fires that threaten lives or property are immediately suppressed.

Wildland Fire Use Fires
Wildland fire use fires are wildland fires that are allowed to burn within an identified, undeveloped area. They are monitored and evaluated on a regular basis. Suppression actions are taken if the fire demonstrates behavior that contradicts resource goals.

Woody
Trees or shrubs.

WR
Wild River.

WSR
Wild and Scenic River.