Sunday, February 08, 2009

North of Rocky Point

Clamber over the bedrock ledges at Rocky Point and you round the corner to find a broad expanse of brand new beach. This wasn't here in the early 1990s, just sand bars and a rapidly eroding bluff. But in the last decade, the bars have emerged as a series of prograding spits and a complex network of lagoons. I don't know of another place on Puget Sound where so much land has been created so recently.

The spits are mainly sand, although there's gravel, too. They are low and it looks like particularly high tides have washed fairly uniformly over the berm.
The pattern of breaking waves suggested there are more bars to the north probably destined to become new spits as this whole complex builds north. This northwestward shore of Whidbey is subject to significant swell down the Strait. This, combined with the abundant sand, leads to the frequent presence of offshore bars - something we don't tend to see much of on Puget Sound. In addition, this whole shoreline (all the way to Deception Pass) appears to be subject to some fairly long cycles of erosion and accretion. Interesting that this area has been accreting during the past decade, while the beach north of the naval air station (2-3 miles) has been experiencing some signficant erosion (Cranberry Lake).

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