Previous studies on Elger Bay, Camano Island, WA hypothesized that the bay has been emptying of stored driftwood since the 1970u27s. To test this hypothesis, we conducted a research project using a combination of field data and historical imagery analysis with Google Earth and ArcGIS to mathematically compare the density of driftwood. Changes in driftwood area may indicate changes in sea level rise, bay subsidence, and/or anthropogenic activity. We found that the maximum driftwood extent was actually closer to the 1950u27s than the 1970u27s. In addition to overall extent we investigated the overall channel flow along Elger Bay by analyzing driftwood movement over time. Using data from different months and years, we were able to compare development of driftwood to analyze the channel flow. Our results indicate that the driftwood is mobile both in the front and back of the bay with annual changes in driftwood area and extent. There is also continuous movement of driftwood along major channels, resulting in changes in the geometry of the driftwood field. We expected to see movement along major channels and in the front of the bay; and driftwood in the back to be stationary. The numerical data disproved the hypothesis that the driftwood area reached a maximum in the 1970s and has been emptying since. Our other observations were consistent with our hypotheses, except for the mobility of driftwood in the back of the bay.
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