Nearshore habitat

In the course of building homes, businesses, roads, and infrastructure, the lands and waters of Puget Sound have been drastically modified. Levees, dams, and toxic deposits are obvious and have site-specific impacts. But less obvious are the cumulative changes from human land use activities, such as bulkheads, docks, permanent removal of native vegetation, and loss of native habitat in marine and upland areas. These activities have damaged the underlying processes that form beaches, keep rivers, estuaries, and forests healthy, and support species. Historically, the actions that led to ecosystem degradation were intended to improve the quality of life for Puget Sound residents, but with closed shellfish beds, flooding, species decline, and other impacts it is clear that ecosystem rebuilding efforts are needed.

More then 700 miles of Puget Sound shoreline is considered to be "armored," and as much as four miles of new armoring is added each year.

Fecal bacteria are found in the feces of humans and other homeothermic animals. They are monitored in recreational waters because they are good indicators of harmful pathogens that are more difficult to measure. 

Puget Sound has over 4,000 km (2,500 miles) of shorelines, ranging from rocky sea cliffs to coastal bluffs and river deltas. The exchange of water, sediment, and nutrients between the land and sea is fundamental to the formation and maintenance of an array of critical habitat types.

"Habitat" describes the physical and biological conditions that support a species or species assemblage and refers to conditions that exist at many scales. An oyster shell provides habitat for some algae and invertebrates, whereas cubic miles of sunlit water in Puget Sound comprise the habitat for many planktonic species.

Non-native species are those that do not naturally occur in an ecosystem. A non-native species is considered invasive when it is capable of aggressively establishing itself and causing environmental damage to an ecosystem. Plants, animals, and pathogens all can be invasive.