Introduction:

Commencement Bay is a major deep-water seaport located in the main basin of the Puget Sound, WA, between Point Defiance and Brown's Point. The bay is about 7.5 km wide at its mouth between Point Defiance and Brown's Point. The bay is about 4.3 km and 4.7 km long along its southern and northern shores, respectively. Depths in the main channel of the bay range from 42 to 185 meters (Cannon and Grigsby 1982).

Prior to development, Commencement Bay was dominated by mudflat and estuarine habitat. See the below picture for a comparison between pre-development and post-development of Commencement Bay. Through dredging and filling, eight waterways have been created in the southern terminus of the bay, and much of the original mudflat and estuarine habitat has been lost (People for Puget Sound 1997). With this development, contamination of sediments has greatly impaired the health of this bay. High concentrations of organic contaminants such as PAHs, DDT, DDE, PCB, HCB, and PAEs, and heavy metals such as copper, lead, arsenic, cadmium, and mercury led to the listing of Commencement Bay as an EPA superfund site in 1983 (EPA 2003, and Konasewich et al. 1982).

Several of Commencement Bay's waterways provide a source of freshwater to the bay. The most significant of these waterways is that of the Puyallup River, which drains 2,538.2 km² from Mount Rainer to the Puget Lowlands. The Puyallup River discharges about 94 cubic meters per second of sediment rich water into Commencement Bay (USGS 2003 (a)). While smaller in both drainage area (43.51 km²) and average annual discharge (0.82 cubic meters per second)(USGS 2003 (b)), Hylebos Creek drains into the Hylebos Waterway, providing yet another source of freshwater. Commencement Bay also receives the effluent of a large municipal wastewater treatment plant. This treatment facility discharges an average of 91 million liters of secondarily treated wastewater per day. The discharge pipe of this plant is located 366 m into Commencement Bay at a depth of about 36.5 m (City of Tacoma 2002).

Given the superfund status and highly degraded nature of Commencement Bay, a large number of parties are involved in restoration, mitigation, damage assessment, and monitoring activities (e.g., EPA, NOAA, NMFS, City of Tacoma, local community groups, and local industries). While the degraded nature of Commencement Bay is unfortunate, it also provides an exceptional opportunity for research. Likewise, Commencement Bay has been the subject of many studies covering a broad range of disciplines, from toxicology to sediment transport.

As part of an effort to monitor Commencement Bay, and to provide students with an exceptional educational experience, the University of Washington Tacoma has conducted surveys within and around Commencement Bay since 2000. Over the past 3 years, areas such as the Tacoma Narrows, Colvos Passage, Dalco Passage, Quarter Master Harbor, and the East Passage have been sampled. However, a majority of the surveys conducted during the past 3 years have focused on eight stations located with Commencement Bay. See the sample stations page for information on the sites that have been sampled by UWT students.

The goal of this website is to present the data collected during current and past surveys of Commencement Bay by UWT, which is presented here in a centralized data repository. Also, a general presentation and analysis of the data collected during these surveys are presented here in the results and discussion sections, respectively. Data collection methods are also presented in this website. Given that this monitoring and educational project is an evolving and ongoing process, links to websites produced by previous students are also provided, in addition to some other useful and informative sites, are provided in the links section.

Literature Cited:

Cannon, G.A., and M.W. Grigsby. 1982. Observations of currents and water properties in Commencement Bay. NOAA Technical Memorandum OMPA-22. 37 pp.

City of Tacoma. 2002. Features of our Central Wastewater Treatment Plant. Available: http://www.ci.tacoma.wa.us/waterservices/wastewater/Treatment_3.htm. Accessed: May 3, 2003.

EPA. 2003. NPL Site Narrative for Commencement Bay, Near Shore/Tide Flats. Available: http://www.epa.gov/superfund/sites/npl/nar993.htm. Accessed: May 11, 2003.

Konasewich, D.E., P.M. Chapman, E. Gerencher, G. Vigers, and N. Treloar. 1982. Effects, pathways, processes, and transformation of Puget Sound contaminants of concern. NOAA technical memorandum OMPA-20. 357 pp.

People for Puget Sound. 1997. The loss of habitat in Puget Sound. Available: http://www.pugetsound.org/habitat/reportfolder/r14puyallup.html. Accessed: May 11, 2003.

USGS (a). 2003. USGS Water Resources: Station Number 12101500. Available: http://waterdata.usgs.gov/nwis/inventory/?site_no=12101500. Accessed: May 11, 2003.

USGS (b). 2003. USGS Water Resources: Station Number 12103020. Available: http://waterdata.usgs.gov/nwis/inventory/?site_no=12103020. Accessed: May 11, 2003.

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