Resources of the North Cascades National Park Service Complex

North Cascades National Park (NP) (204,374 hectares), Ross Lake National Recreation Area (NRA) (47,350 hectares), and Lake Chelan NRA (25,091 hectares) comprise the North Cascades National Park Service (NPS) Complex (see map). The park complex was established on October 2, 1968. The Washington Park Wilderness Act of 1988 established 256,828 hectares of the Complex as the Steven Mather Wilderness. There are five designated and two proposed Research Natural Areas within the park.

The park complex is located in the North Cascade physiographic province in northwestern Washington. It is bounded on the west, south, and east by 1.9 million hectares of National Forest lands, of which 763,890 hectares are designated wilderness. Most of these wilderness areas are contiguous to the Stephen Mather Wilderness. The North Cascades NP northern boundary is the international boundary with the Canadian province of British Columbia. Provincial forest lands and a recreation area are adjacent to the boundary in British Columbia; a provincial park is just to the east.

The North Cascades NPS Complex spans the Cascade crest, placing within its boundary two major biogeographic zones: temperate marine and semi-arid continental. The climatic and biotic diversity are further increased by a transitional zone, roughly the lower elevations of the Ross Lake drainage. The third zone is created by an orographic divide west of the crest. Vegetal and climatic characteristics within this zone are intermediate between the mild, wet conditions typical of the west side and the semi-arid conditions typical of the east side.

The park complex is characterized by deep, forested valleys between high, glaciated mountain peaks (see map). The local topographic relief is 8,800 feet with the lowest point being 400 feet along the Skagit River and the highest elevations occurring on several mountain peaks over 9,000 feet. The bedrock geology of the North Cascades differs greatly on either side of the Straight Creek Fault. West of the fault the Shuksan metamorphic suite is composed of green schist and phyllite. East of the fault are granite and gneiss, which compose a crystalline core of the North Cascades. The park complex has been shaped by a combination of uplifting of predominantly granitic formations and substantial glaciation. Watersheds typically begin in high-elevation glaciers and snowfields, dropping in numerous cascading streams down precipitous valley walls to classic, U-shaped valley floors carved by glaciers during the Pleistocene. Mainstem streams are generally sinuous and braided across relatively broad, flat valley bottoms.

Precipitation varies across elevation gradients and the crest of the North Cascade Range, with an average of about 400 cm/yr on the western peaks to an average of 50 cm/yr in the Lake Chelan corridor. The intermediate zone within the lower elevations of the Ross Lake basin averages between 100 and 150 cm/yr precipitation; the slopes to the west and east of the valley typically receive 150 to 200 cm/yr.

A 1971 inventory identified 318 glaciers in the North Cascades NPS Complex: more than all of the other national parks within the conterminous states combined. From the glaciers, permanent snowfields, and 245 lakes flow approximately 6,500 km of rivers and streams (excluding intermittent streams, which may increase the total to over 10,000 km). North Cascades NP contains the headwaters for three major river systems: the Columbia, Fraser, and Skagit.

There are three reservoirs within Ross Lake NRA, all behind dams built to provide hydroelectric power. A small hydroelectric project on Newhalem Creek provides further power via a stream diversion. Lake Chelan, which developed within a deep, glacial trough, is the third deepest natural lake in the United States. It was dammed in the 1920's to regulate its elevation for hydroelectric power. All four reservoirs provide recreational opportunities and transportation routes as well as power. Dams also influence stream processes downstream and the migration of fish throughout the watershed. Reservoirs affect microclimate, cause erosion of terrestrial habitat, and limit the ranges of terrestrial species.

The abundance of water and the wide variation in landforms, soil types, elevation, slope, and aspect create many types of habitat that support a diversity of flora and fauna. There are 75 mammal species, 200 bird species, 28 fish species, 17 species of reptiles and amphibians, and some 1,577 species of vascular plants within the park complex. Of these, 2 mammals, 6 birds, 3 amphibians, and 57 plant species are listed federally or by the state of Washington as threatened or endangered; an additional 4 mammals, 10 birds, and 1 fish species are candidates for federal and/or state listing. About 260 non-native plant species are also found, including diffuse knapweed, spotted knapweed, rush skeletonweed, St. Johnswort, Scotch broom, Japanese knotweed, foxglove, and common mullein. Non-native stocks of rainbow trout, cutthroat trout, brook trout, golden trout, and kokanee salmon are also found within North Cascades NPS Complex.

Visitors from around the world enjoy the many resources of the North Cascades NPS Complex. This includes the use of frontcountry roads, campgrounds, and trails, as well as backcountry hiking, skiing, and climbing. Ross Lake and Lake Chelan NRA's are particularly popular destinations for water-related activities during the summer months. The majority of recreational visitation occurs during the summer, because winter access is restricted due to extended snowpack and the approximately five-month closure of the North Cascades Highway.

North Cascades NPS Complex also contains a rich cultural and historical heritage. Native Americans have used the area now contained within the park for thousands of years. Their activities throughout the North Cascades can be inferred through artifacts associated with settlements, trade routes, and historical accounts through contact with Euro-American settlers. There are hundreds of designated archeological sites in the park complex with many others remaining to be discovered. In addition, the park has ongoing communication with contemporary Native Americans in the region with respect to subsistence use of resources and other activities within the park. North Cascades NPS Complex also has a significant record of the travels and activities of settlers and post-settlement activities that have affected current transportation and modern-day settlements in and near the complex.