Tuesday, March 03, 2009

Port Gardiner




The shoreline runs almost east-west between Elliott Point (Mukilteo) and Everett and the result is beaches with exposure from the north, but that are largely protected from the more common southerly storm waves. Drift still tends to be west to east (towards Everett), but the shoreline is largely swash-aligned and net transport rates are probably pretty low. The shoreline intersects several north-trending stream gullies - Japanese Gulch, Powder Mill, Merrill and Ring, Pigeon Creek, and others. Each stream emerges through a culvert under the railroad grade and spills across a small delta.

The protruding deltas may act a bit like groins, segmenting the shoreline into somewhat independent compartments. And the stream deltas probably greatly complicate cross-shore sediment behavior - gravel gets transported by waves higher on the beach, but then gets transported offshore by the streams during lower tides. Whether or not the streams are major sources of terrestrial sediment (debated), the stream deltas are probably signficiant sinks for coastal sediment.

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