Saturday, March 22, 2008
Named after an early resident, this low point of land on western Samish Island is now Camp Kirby.
Cuspate forelands generally occur on shorelines where there is significant wave action from two, nearly opposite directions. This leads to converging longshore sediment transport, which in turn forms a triangle (cusp) of low land in front of the coastline (foreland). They are often assymetrical, due to differences in wave regime, sediment supply, or coastline orientation. They usually have wetlands or lagoons in the middle, sometimes with a tidal inlet along one side (what I call a limb). The assymetry also applies to the long-term evolution of the feature. Many are eroding on one limb and accreting or stable on the other, leading to gradual shifting in the shape or position of the landform.
The northwest beach is steep. The storm berm is narrow and is rolling back across the lower ground behind it. The vegetation line is distinct and relatively straight. There are few drift logs. The berm crest appears to be slightly higher than the berm on the southeast side. It looks like this beach has more gravel and less sand than the beach on the other side. I suspect this beach sees fewer, but perhaps bigger, storm waves. It is drift-aligned (oblique to waves and extending in the direction of drift).
The southeast beach is flatter. There are multiple berms and they are less distinct than the one on the north side. The backshore and the berms are covered with drift logs (typical of south-facing beaches on the Sound). In map view, this beach is concave seaward and is swash-aligned - oriented perpendicular to the greatest fetch. As a result, the southeastern limb acts like a big pocket beach. There is no place for the gravel and coarse sand to go. It may get more frequent wave action than the other side, but it may also be broadening.
Thursday afternoon the winds were blowing from the south, breaking parallel to the south beach and refracting around the point to break northward along the northern beach. At the very tip of the spit, the waves were actually breaking against each other from opposite directions.
The pill box at the end was reportedly built to serve as a shooting blind, but now is a rectangular tide pool in which eagles have apparently drowned. A historic relic that might be better off gone?
Shoreline restoration. Bulkheads get lots of attention these days, but restoration of bulkheaded shorelines is often more about removing fill. We once called burying the beach "reclamation." Unburying it should be called the same thing. To reclaim the high-tide beach, we may need to give up some lawn, which will upset the Canadian Geese, but the kids will be just as happy playing among the logs in the sand.
Bulkheading of naturally eroding shorelines is a very real problem, but we shouldn't confuse our devils. In this case, the bulkhead is simply a decoration (albeit a slightly toxic, creosoted one) on the seaward edge of a big pile of dirt - which happens to lie on top of a perfectly good beach.
Wednesday, March 12, 2008
A private beach where dynamite was once manufactured and loaded on ships. The pier is about all that remains of the old Atlas plant. Now this site is part of the huge new subdivisions crawling out of Lacey. At least here, the houses will be kept way back from the bluff and the beach will remain a wild one.
This is a pretty sandy beach, though in many places covered with a veneer of gravel. There were barnacles growing on the top side of 2" pebbles, suggesting that it has been few years since there has been a north storm big enough to roll them around (this is a north-facing shoreline, so the more common southerlies have little impact). There was a wide, sloping terrace. I am always impressed by the height and width of south sound beaches - a result of the much higher tidal range down here than farther north.
There is an abandoned boat just southeast off of Beachcrest. There was an wrecked car at the bottom of the bluff - I suspect someone pushed (drove?) it over the edge many years ago. And even a recently abandoned bicycle. And then there's the old pier. So it's not completely wild - but it was close.
I arrived near this same spot last June, from the other direction. The shoreline that extends northwest from the mouth of the Nisqually crosses a series of small drainages. They originally formed when sea level was lower and have subsequently been flooded, resulting in a series of drowned valley estuaries. Spits have formed across most of their mouths, creating what I call barrier estuaries, but which belong to a more general class of features on Puget Sound most of us call "pocket estuaries." The name fits.
There are lots of these in southern Puget Sound. The sea level history is more conducive to them here than farther north. It rains more down here, so the drainage networks are more developed. And there has been less wave erosion to smooth out the coast and remove little divots like these. There are intertidal deltas at the mouths of each of these that are part stream delta, part ebb-tide delta. I suspect much of the wood scattered across the beach was flushed out during the December storm.
Every spring, we bring a new class down here (March 2006). This year the wind was howling from the south, but the rain stayed away. Sand was blowing across the beach out at the point itself, rippling the surface and swirling around the logs. No wonder this is one of those rare Puget Sound backshores where small dunes are common.
Sometime a century or more ago, a large ship wound up on the beach just north of the point, where much of it still remains, subtly shaping the mid-beach sand and gravel. If Kala Point had been developed a decade earlier, there probably would be a long row of big houses on the beach - but instead, they kept the houses up on the hill and left the beach as common space.
The trail down the bluff follows the old road down to the pier. The pier is gone, but there are a few picnic tables on a little lawn that sticks 60 feet across the beach. Riprap and old concrete keeps it from washing away too fast. Most of the fill could be removed and there would still be room for a picnic tables and a much friendlier path to the beach than scrambling over the rocks.
There are beautiful undeveloped bluffs both north, towards the mill at Glen Cove, and south, towards Kala Point. The platform from here north broadens and the falling tide was exposing extensive sand and gravel bars. As you walk north, you pass some steep bluffs and recent landslides, and then the berm widens to form a narrow fringing barrier that extends 0.5 mile along the shoreline. Young cedars, some of which have sprouted in the old logs that stranded on the berm, are well established along this flat ribbon of backshore at the base of the old bluff. Some of these cedars were dying, perhaps as erosion reclaims this beach or as the salt water reaches farther landward. I suspect this wide beach may be a fairly modern phenomenon, dating from earlier in the century when logs were rafted offshore of this beach and the wave regime may have been quite different.
Sunday, March 02, 2008
The British call these shingle beaches. There were some good skipping stones - some the size of frisbees. And some car parts, the leftovers from the pile of junk dumped over the edge of the bluff before the dump became a landfill.
Dry Creek is a dry (most of the time, at least) gully that reaches the Strait between the mouth of the Elwha River and Ediz Hook, midway along a littoral cell of considerable notoriety. West of Dry Creek, there is over a mile of beautiful high bluffs and wild beach. East of Dry Creek, there is over a mile of riprap, protecting an old waterline that engineers cleverly and conveniently laid on the beach. Almost as clever and convenient as dumping 50,000 cubic yards of cobble on Ediz Hook every five years to keep the spit from self-destructing - all because the natural sources of gravel (from the river and the eroding bluffs) were eliminated.
This beach has been the site of a recent unfortunate accident (something one tries to avoid, but happens anyway). On the bright side, the 700' monument gives us a stunning preview of what the rest of Puget Sound may look like when sea level is two feet higher.