NEWS NOTES ON SUSTAINABLE WATER RESOURCESPuget Sound Sound (/ˈpjuːdʒɪt/) is a sound of the Pac...


Puget Sound

Puget Sound (/ˈpjuːdʒɪt/) is a sound of the Pacific Northwest, an inlet of the Pacific Ocean, and part of the Salish Sea. It is located along the northwestern coast of the U.S. state of Washington. It is a complex estuarine system of interconnected marine waterways and basins, with one major and two minor connections to the open Pacific Ocean via the Strait of Juan de Fuca—Admiralty Inlet being the major connection and Deception Pass and Swinomish Channel being the minor.

Water flow through Deception Pass is approximately equal to 2% of the total tidal exchange between Puget Sound and the Strait of Juan de Fuca. Puget Sound extends approximately 100 miles (160 km) from Deception Pass in the north to Olympia in the south. Its average depth is 450 feet (140 m) and its maximum depth, off Jefferson Point between Indianola and Kingston, is 930 feet (280 m). The depth of the main basin, between the southern tip of Whidbey Island and Tacoma, is approximately 600 feet (180 m).
In 2009, the term Salish Sea was established by the United States Board on Geographic Names as the collective waters of Puget Sound, the Strait of Juan de Fuca, and the Strait of Georgia. Sometimes the terms "Puget Sound" and "Puget Sound and adjacent waters" are used for not only Puget Sound proper but also for waters to the north, such as Bellingham Bay and the San Juan Islands region.

Continental ice sheets have repeatedly advanced and retreated from the Puget Sound region. The most recent glacial period, called the Fraser Glaciation, had three phases, or stades. During the third, or Vashon Glaciation, a lobe of the Cordilleran Ice Sheet, called the Puget Lobe, spread south about 15,000 years ago, covering the Puget Sound region with an ice sheet about 3,000 feet (910 m) thick near Seattle, and nearly 6,000 feet (1,800 m) at the present Canada-U.S. border. Since each new advance and retreat of ice erodes away much of the evidence of previous ice ages, the most recent Vashon phase has left the clearest imprint on the land. At its maximum extent the Vashon ice sheet extended south of Olympia to near Tenino, and covered the lowlands between the Olympic and Cascade mountain ranges. About 14,000 years ago the ice began to retreat. By 11,000 years ago it survived only north of the Canada–US border.

Over the past 30 years, as the human population of the region has increased, there has been a correlating decrease in various plant and animal species which inhabit Puget Sound. The decline has been seen in numerous populations including forage fish, salmonids, bottom fish, marine birds, harbor porpoise, and orcas. The decline is attributed to the various environmental issues in Puget Sound. Because of this population decline, there have been changes to the fishery practices, and an increase in petitioning to add species to the Endangered Species Act. There has also been an increase in recovery and management plans for many different area species.