NATURAL ENVIRONMENT

The Central Whidbey Island community places great value on the protection of the natural environment. The community has been active in supporting the development of land use restrictions on historic prairies, farmland, salt marshes, freshwater wetlands, unique native plant communities, and wildlife habitat. The political activity has been matched by the communitys philanthropic support for conservation easements and outright public/private purchases of significant properties. The political and philanthropic activity is anchored by an extensive volunteer base committed to environmental protection. In the current comprehensive planning process the Port re-affirmed its commitment to continue to prioritize environmental protection in evaluating opportunities and guiding development of their properties.

Climate: Central Whidbey Island has a generally mild and uniform marine climate for a number of reasons: a narrow range in elevation, the tempering effect of the Pacific Ocean, the rain barrier created by the Olympic Mountains and the Cascade Mountains role in deflecting continental winds. The average rainfall in Central Whidbey is approximately 18-21 per year, well below the average Whidbey Island rainfall of 30 per year. About 80% of the rainfall occurs October-May. Average temperatures range from 41-58 degrees Fahrenheit, with common occurrences of below freezing temperatures in the winter, and summer days in the 90s. Relative humidity normally runs from 40% to 90%. The growing season is estimated to be approximately 180-220 days per year. Freezes are usually light and do not continue past February. An average of 255 days with cloud cover and 43 days of clear skies are reported annually. Prevailing winds come from the south and southwest in the winter, and the north and northwest in the summer.

Geology/Topography: Whidbey Island is 45 miles long with 148 miles of shoreline, the longest island in the contiguous United States. The major surface features of Whidbey Island were shaped by glacial advances and recessions. Central Whidbey ranges from sea level to 580 feet above sea level. The elevations above 200 are typically rolling hills and plains. The lower elevations are home to fertile agricultural valleys, terraces and prairies. Much of the land below 200 is shoreline abutted by steep slopes and cliffs, and in some places sloping ravines. Lagoons, saltwater tidal flats, marshes, shallow brackish lakes, freshwater kettle ponds, and accretion beaches cover the coastline.

Soils: The soil layer in Island County is relatively thin, with glacial drift being the primary foundation material. The last glacial recession left deposits of boulder-clay layers on most upland areas and outwash sands at the lowest levels. The sands were covered with till and later marine drift gravels, which resulted in a cemented gravel material. This provides satisfactory surface drainage on sloped areas but impermeable subsurface drainage. Glacial upland soils comprise about 75% of the total area. This has resulted in surface soils ranging from fine textured to coarse materials, which provide moderately good to somewhat excessive drainage. The Port Tract at the Greenbank Farm is predominately these poor soils types. Glacial recession washed sediment from upper slopes into glacial lake bottoms which mixed with organic matter to form the fertile soils of the prairies. At least 45% of the best farmlands (USDA Class II) in Island County are found in the Coupeville area of the Port District. The wetland mineral soils and organic wetland soils which exist in the Port District are poorly drained soils with shallow water tables.

Vegetation: Central Whidbey Island is located in the Western Hemlock Forest Zone of Western Washington. The mature climax forest is Western Hemlock and Western Red Cedar, and the sub-climax forests are Douglas Fir. Essentially all of the virgin timber in Island County was logged or burned by 1900. Second and third growth Douglas Fir, mixed alder and thick underbrush salal, Oregon Grape and ferns now dominate the forest areas. Garry Oak, maple and madrone trees, rhododendron, salal, and a wide variety of smaller plant species are also found. There is a wide variety of salt marsh and beach vegetation that is effected by the wind and tides, and human use. Central Whidbey Island is home to one of the only two remaining glacial outwash prairies in the northern Puget region with endangered native lowland grasses. For example, Golden Paintbrush is known to exist in only thirteen places on earth. Five of these are on Whidbey Island. There is also a wide range of flora species, due to the diverse habitat zones in Central Whidbey Island.

Hydrology: The Port District contains a multiplicity of both marine and freshwater surface water resources. It is bounded by Penn Cove, Saratoga Passage, Admiralty Inlet and numerous saltwater lagoons, small bays and inland salt marshes. Freshwater and subsurface water resources are more limited. Aquifer recharge is solely through precipitation. Due to the low rainfall levels in Central Whidbey Island, the risk is increasing for groundwater pumping to exceed the aquifers capacity to recharge. There is an increasing problem in some areas of saltwater intrusion. There are approximately two dozen identified watersheds in the Port District

Fish and Wildlife: The fish and shellfish habitat is abundant around Whidbey Islands saltwater shoreline. Visitors and residents share the recreational pursuit of clams, crabs, shrimp and mussels, as well as salmon and other Puget Sound fish species from the shore and private boats. Penn Cove is home to the only commercial aquaculture operation in the Port District, cultivating blue-mussels. However, there are many commercial entities harvesting shellfish from Whidbey Island waters. The diversity of Whidbey Island habitat provides homes, feeding grounds, migratory resting places and wintering grounds for a wide range of birds.

** Data was drawn from the Port of Coupeville Comprehensive Scheme of Harbor Improvements (1985), Ebeys Landing National Historical Reserve Draft General Management Plan and Environmental Impact Statement (Volume I, September 2005) and the Island County Economic Development Council.

Port of Coupeville Comprehensive Plan 2007-2026