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The United States Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) is conducting a pilot study in the western United States. This study will advance the science of ecological monitoring and demonstrate techniques for regional-scale assessment of the condition of aquatic resources in the 14 western states in EPA Regions 8, 9, and 10 (shown below). This browser is a demonstration of a versatile communication device for our landscape ecological assessment products, reports, assessments, data studies, and analysis tools.

image of western study areas

Human stresses on the natural resources of the United States are intense. These pressures have resulted in many unintended changes in our ecosystems -- loss of biodiversity, increases in the number of endangered species (e.g. salmon), habitat degradation, and increases in contamination and pollution. Major public and private efforts have gone into controlling pollution, and protecting and restoring natural resources and the ecosystems they depend on. Corrective actions have, and will continue to have, an impact upon how we all lead our lives. We react to the problems that are most visible and thus receive the greatest amount of publicity. To make the most of our environmental efforts, we need to understand and assess the status and trends in the condition of our ecological resources and the stressors affecting these systems. It is not at all clear that we are currently targeting financial resources and/or lifestyle changes on problems or at locations where they will have the most effect.

The landscape component of the Western Pilot Study provides information that has multiple management implications. Regional Landscape products will be provided to assess the spatial distribution of landscape stressors on aquatic ecosystems across each region. This will assist regional managers in understanding how landscape conditions contribute to varying aquatic resource conditions. As such, the products also will contribute to formulation of specific management actions for different geographic locations within each region. The first step in providing regional products will be to test and demonstrate landscape assessment methodologies on sub-regional areas of high importance to each Region. This browser concentrates on the Region 9 Northern California pilot area.

Northern California Pilot Study Area

The Western EMAP Northern California Pilot Study Area (NCPSA) is a contiguous tract of land located in the mountainous and coastal areas of the northwestern portion of the State of California and southernmost Oregon along all but the easternmost extent of the California-Oregon border. The NCPSA occupies approximately 67,104 km2 (25,909 mi2 ) in land area and is somewhat triangular in shape. The study area boundary includes the Pacific Ocean coastline from Tomales Bay in California extending to the mouth of the Rogue River in Oregon on the west, trends along the Oregon-California state line to near Goose Lake on the north, and follows the western edge of California's Central Valley to a location near the community of Petaluma on the east and south.

US Route 101 runs the entire length of the western side of the NCPSA, while Interstate 5 cuts through the north-central expanse of the study area. Many other, smaller federal, state, and county routes, including California Route 1 (Pacific Coast Highway) weave throughout the study area, some of which connect to one or both these two major travel routes. The Pacific Crest National Scenic Trail also winds throughout the higher elevations of the northern portion of the study area. Two distinct mountain ranges dominate the NCPSA, the Coast Ranges (coastal mountains) and the Cascade Range. The Klamath Mountains province, which lies near the Pacific Ocean in northwestern corner of California and extends north into Oregon, is composed of metamorphic and granitic rock. South of the Klamath Mountains, the Coast Ranges, which are situated close to the edge of the continent and extend from Humboldt County to the southernmost extreme of the study area, form a series of low mountains that parallel the coast. The other major mountain formation is the volcanically active Cascade Range located in the north-central portion of the study area. Most of the mountain peaks in the NCPSA rise to less than 2750 m (9,000 ft) above sea level, with the exception of Mt. Shasta which, at 4317 m (14,162 ft) in elevation, is situated at the southernmost extreme of the Cascade Range and is the highest point in the study area. In addition, the far-northeastern corner of the NCPSA is classified as the Modoc Plateau, an area of volcanic tablelands east of the Cascades and is part of the larger Columbia Plateau. The average annual precipitation varies greatly within the study area, ranging from an approximate low of 380 mm (15 in.) in the Modoc Plateau region to well in excess of 2500 mm (100 in.) in the temperate rainforests of coastal mountains on either side of the California-Oregon border. Although no major rivers are found within the NCPSA boundaries, many medium-sized, locally significant rivers such as the Trinity, Eel, Russian, Klamath, and Rogue, and their tributaries, wend their way through the study-area mountains and empty into the Pacific Ocean either directly or via the Central Valley rivers flowing into San Francisco Bay.

Approximately one-half of the land area within the NCPSA boundary is administered by the USDA Forest Service, a portion of which is designated as wilderness. The Bureau of Land Management and the State of California also administer significant tracts of land within the study area. In addition, several national recreation areas, national parks, national monuments, and other federal lands and Indian reservations are found inside the NCPSA. The Cascade Range and Coast Ranges are also peppered with privately owned/commercial forest lands, with a significant amount of private holdings concentrated along the coastal regions. The forests, which are located in the higher elevations of the study area, are both hardwood- and conifer-dominated and include redwood and various species of oak, fir, cedar, and pine communities. Shrublands, rangeland, and agricultural lands-most notably for viticulture--are found in the lower elevations of the study area and the arid Modoc Plateau supports primarily Great Basin (i.e., cold desert) vegetation dominated by sagebrush, bunchgrass and cheatgrass interspersed with sparse to dense piņon-juniper woodlands. The forests sustain such large mammals as black bear, deer, various species of elk, pronghorn antelope, and mountain lion. Urban areas within the NCPSA are predominantly found along one of the major transportation corridors identified above.



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