White River

Oregon

Designated Reach: October 28, 1988. From Mount Hood National Forest to the confluence with the Deschutes River.

Classification/Mileage: Scenic — 24.3 miles; Recreational — 22.5 miles; Total — 46.8 miles.

The White River lies east of the Cascade Range and south of the Columbia River Gorge. Originating on Mt. Hood, the river flows for approximately 53 miles to its confluence with the Deschutes River just above Sherar's Bridge. All but 0.6 miles of the river at White River Falls is designated as a wild and scenic river. The U.S. Forest Service manages the upper three segments, A-C, and the Bureau of Land Management managers the lower three, D-F. The river's outstandingly remarkable values include geology, hydrology, botany, fish habitat and populations, wildlife habitat and populations, cultural resources, recreation and scenery.

The river's unique hydrology includes its color in late summer and early fall and its isolation from other rivers. As the leading edge of White River glacier melts in late summer, it releases large amounts of silt and sand which settle out and cover much of the channel bottom. This sand and silt give the river a milky appearance, and provide the source for its name.

The river flows through a wide variety of life zones with many sensitive and unique plant species found only in this area, including a genetically unique race of redband rainbow trout. It offers outstanding opportunities for a wide variety of recreational activities, including Nordic skiing, photography, camping, rugged hiking, and nature and wildlife observation.

Segment A begins with an active fumarole field, known as "Devil's Kitchen," and at White River glacier. Immediately below the glacier lies a mixture of andesite, dacite flows with pyroclastic and mudflow deposits, known as the Old Maid flows. These flows occurred about 260 years ago and buried a forest on the slopes of Mt. Hood. Recent down cutting by the White River and its tributaries has exposed portions of this "Ghost Forest" along with several of the Old Maid flows in a sequence of terraces along the valley edge upriver from the Highway 35 crossing. Below the Old Maid deposits lies a broad outwash plain strewn with boulders.

Average annual precipitation on Mt. Hood exceeds 130 inches at the glacier. Most precipitation falls as snow, peaking in winter. Along its upper four miles, the river drops 830 feet per mile, producing a relatively high gradient. The glacial outburst floods cause the river to change course and create a large, sandy floodplain. The river shifts channels across this plain, tending to flow either towards Mineral Creek or towards Iron Creek. At present, the river flows into Iron Creek.

Most of Segment B consists of a U-shaped valley, containing remnant glacial moraines, glacial erratics, a kettled lake and another ghost forest. Immediately adjacent to the river is a series of sand flats, some of which contain a pebble armor surface. The armored sand flats are particularly fragile and susceptible to disturbance from wheeled vehicles. This segment includes a portion of the Barlow Road, an important alternative route along the Oregon Trail.

Segments A and B contain the highest biological diversity and complexity of the river corridor. The uppermost portion of the river is rocks and ice, ranging bogs and associated species in the poorly drained portion of the floodplain to mixed-conifer zone in Segment B. At the lower end of Segment B, the river enters a narrow V-shaped valley.

Segments C and D flow through a steep V-shaped canyon. The canyon walls, a series of steps formed by benches and rock walls, consist of alternating layers of fluvial sediments, ash flows and lava flows. The climate in these two segments continues to become dryer. Precipitation ranges from 50 inches at the beginning of Segment C to 30 inches at the lower end of Segment D. Segment C contains Keeps Mill and flume, an early development for water and timber. Segment D contains an historic waterwheel and other historic structures.

Segments E and F contain the oldest rocks in the White River. The 14.5 million year old French Springs Member of the Wanapum Basalt lie over the 15 million year old Grande Ronde Basalts. The climate is hot and dry with as little as 10 inches of annual precipitation at the river mouth. Vegetation consists mostly of shrubs, forbs and grasses. Viewpoints from highways 197 and 216 offer a scenic contrast between the riparian vegetation and the desert steppe.