Sunday, January 10, 2010

Point Heyer

It is called Point Heyer on the maps but is known locally as KVI Beach, after the radio transmitting tower on the point.

Point Heyer is a recurved spit, shaped primarily by winds and waves out of the north, and is the terminus of a littoral cell that collects sand and gravel from two miles of eroding bluffs and small streams. As usual, most of the wind comes out of the south, but Maury Island limits the fetch, so northern waves have much more influence. The southerly winds are still more than enough to pile the drift logs up into the northern corner of the marsh (within the lagoon itself, wind moves the logs, not the waves).

The spit is hooked around to the west, into Tramp Harbor, and the tidal inlet is pushed to the farthest end. The eastern limb is narrow, consistent with a barrier beach migrating westward in step with the retreating bluff to the north. The western limb is broad, since it is the ultimate resting place for much of this sediment moving down the shore. We often call these landforms accretion beaches or depositional landforms - because they have built over long periods of time seaward of the original coastline. But that doesn't mean they are actively accreting. In this case, the eastern limb is erosional - or at least maintaining a state of dynamic equilibrium (if your house was built on it you would call it erosion), but the western limb is truly accretional.

It's hard to find a tidal marsh in this part of the Sound. There used to be more, but these small estuaries and lagoons were easy targets for early settlers and small industry and most were filled by the early part of the last century.

No comments: