Land Cover 

Forests are essential for maintaining the integrity of our watersheds and ecosystems. They provide crucial habitat to salmon, eagles and a host of other species, some of them threatened with extinction. Healthy forests moderate the climate and improve air and water quality by removing contaminants from the air, and purifying and storing water. Sustainable forest management can generate jobs and economic benefits for the region. Forests, urban parks and open space provide people with recreational and therapeutic benefits. Diverse landscapes are necessary to sustain the variety of plant and animal species that comprise healthy ecosystems.

• Historically, King County was covered by lush forest from mountains to tide water. Most of the old growth is now gone, but forests still covered 64% of King County in 2007, much of it regenerated forest (data not shown).

• Urban sprawl creates impervious surfaces, causing a host of environmental problems. Impervious surfaces contribute to storm water runoff and increased risk of flooding, instead of recharging ground water and wetlands. The land and vegetation along stream banks are important natural biofilters, protecting aquatic environments from excessive sedimentation, polluted surface runoff and erosion. They supply shelter and food for aquatic animals and shade that is an important part of stream temperature regulation. (figure 1) Between 1991 and 2001, impervious surfaces along stream banks expanded in King County, consistent with loss of forested lands along these same streams, as seen in the chart above.

• Approximately 1,000 linear miles of roads were built in King County in the past 26 years, creating access to undeveloped lands for new home building and related development (data not shown).

• In addition to more roadways, the size or “footprint” of homes impacts surrounding landscapes and affects the use of resources such as energy and water. (figure 2) After significantly decreasing during the World War II era, new home sizes increased through the boom years of the 1990s. New home sizes have been decreasing over the last several years.

• King County had more than 25,000 acres of urban parks and open space in 2006, about 15 acres per resident. The National Recreation and Park Association recommends 10 acres of park space per thousand urban residents. (figure 3)Urban parks and open space have been steadily growing, although 2006 showed a slight decline, possibly due to continued population growth while no new lands have been added to the parks and open space lists.

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