The Puget Sound

From the Pacific Ocean via Admiralty Inlet, over 4.3x10⁵ million gallons of saltwater enters the Puget Sound daily. Within the Puget Sound watersheds there are 115 cities with a combined population of over 5.3 million residents. The entire Puget Sound region, including the Strait of Juan de Fuca experiences a semi-diurnal tide cycle, with two high tides and two low tides commonly occurring during an approximate 25 hour period. Puget Sound is affected by one of the largest tidal fluctuations in the world. On average the tides range from -4.5ft to +14.5ft, a difference of 10ft but in extreme areas such as the port of Seattle can see differences of up to 18ft. (Navy 1996).

Data was gathered at each area in a number of specific coordinates which are referred to as 'stations'. The parameters of studies included physical conditions, chemical analysis, biological and geological measurements. All data was taken back to the lab for analysis. The sample data that was collected at each station included: temperature, salinity, density, oxygen, fluorescence/chlorophyll, transmissivity, nutrients, phytoplankton, zooplankton, sediments, and microplastics. The description of the methods used at each sampling station can be found on the [Methods] page.

The Puget Sound is a large estuary and there are many factors that influence its waters, including its watershed and freshwater inflow, oceanic saltwater influx, natural and human influenced runoff and wastewater treatment effluent. How the water is circulated and flushed is a complex equation of tidal processes, bathymetry, geographic configuration, and the impacts of a growing population.