Wednesday, January 28, 2015
Driving along U.S. 101, most folks have seen this view up Sequim Bay. This is where the Jamestown S'Klallam Tribe is based and in the last few years they have provided some great places to enjoy the scenery. This view, from the tribal center, looks out over Blyn Spit. For years, I have been able to judge the higher tides as I drove past simply by noting how much of the spit was submerged.
This spit, shaped by northerly winds and waves on the southeastern side of the bay, is typical of small spits in relatively low energy areas (see previous post from Maynard's Lagoon on Discovery Bay). The lack of strong winds and wave run-up prevents the berm from growing as high as in more exposed locations. The lack of coarse gravel and perhaps, the lack of large wood (which tends to blow north and often doesn't build up as much as on these north-facing spits), may also contribute to the lower berm.
In this picture, taken at roughly Mean Higher High Water (MHHW), the spit has almost, but not quite overtopped. Many high tides wash over this feature, which probably doesn't rise more than 1-2 feet above MHHW, explaining why salicornia (pickleweed) dominates the berm ridge, not beach grass and other higher elevation backshore plants.
Someday, I'll head out to Travis Spit, a few miles north at the mouth of the bay, and post some comparison shots to show what a higher energy spit looks like. For one thing, the berm is considerably higher and only very rarely would be completely submerged.