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This beach on the northwest side of Whidbey Island, just outside of Deception Pass, isn't quite on the open ocean, but it still made a good Pacific Coast terminus to my trek across North America. The adventure didn't include too many beaches, but there were some, and I've tried to capture those in the previous posts.
West Beach, because it faces the exposed Strait of Juan de Fuca, displays more of the characteristics of higher energy beaches - including the development of offshore bars - than most beaches on the Salish Sea. It's also a fairly robust barrier, with beach ridges and dunes and a back barrier lagoon (Cranberry Lake: March 2007).
The smaller beaches below the bridge that face on Deception Pass itself are very different and a little hard to figure out (Deception Pass: May 2016). They look much more like pocket beaches, although the orientation is tough to characterize and I doubt they're closed to sediment transport - either in or out.
Presumably, my bike will be less of a feature in my subsequent posts. It was sort of hard to avoid in this recent batch since it was a critical part of my visits. Anyone who's interested in more of the backstory to the bike trip can check: Biketrip2019: Backroads and Bikepaths.
This was pretty much the best possible place (and conditions) to end a field trip on my last day in the field as a professional! The concrete artwork was colorful in the sunshine. The beach provided a great contrast to the three other beaches we'd already visited earlier in the day (Custom Plywood, Bowman Bay, and Cornet Bay). And after a fairly minimalist geologic overview, the participants went back to throwing stones and climbing on the logs until we all had to run off to catch our ferries.
West Beach: February 2013
While the fulcrum of my work-life balance is about to shift dramatically, I plan to continue Gravel Beach. This year has been a slow one on the blog and that may not pick up right away - it has been a distracting few months and my summer and fall will likely be in the mountains and the Interior (not so many beaches). And finally, I have big issues with the platform: Blogger is not very mobile-friendly. The blog takes a lot of time (at least when I'm posting much). And Google has put virtually nothing into supporting it for years. I'll keep playing around with other sharing options - some of which are linked over on the right (desktop version) - and will certainly let folks know if I decide to make big changes.
If you're going to build a town on the water, it makes sense to find a piece of ground that's low enough to allow easy access to the town pier, yet high enough so the town doesn't flood every December. You want to pick a shoreline sheltered from the prevailing winds on a relatively protected bay.
Building over the water made sense in a 19th-century maritime community and the high bank lead to buildings that sort of spill over the bluff -- people and wagons approached on the upper floors, boats pulled up below. Stairs and hoists and gangways connected the two. Early Seattle - along the central waterfront - developed similarly. As did many towns in many other parts of the world.
In many places - Langley, Seattle - development eventually led to foundations being built to replace the piles or to the beach being filled behind a community seawall of some sort. Some of this happened here in Coupeville, too, but in some spots the beach remains, between and beneath the buildings.
The low shoreline of Mutiny Bay once consisted of a complex series of wetlands, tidal inlets, and northerly-directed sand spits. But these low areas also lend themselves to development. Wetlands were diked and plumbed and tide-gated. Inlets were filled in. And small fishing resorts, and later residential beach communities, were built on the spits. But the whole place is still little more than a big bunch of shifting sand bars. And there is a lot of sand in this system, particularly compared to many other beaches on Puget Sound.
There is a boat ramp at the end of Robinson Road (Mutiny Bay: February 2010), but like some other ill-fated boat ramps on South Whidbey (Maxwelton: July 2016), the ramp is regularly, and increasingly, buried by the accreting beach. Clearing it has turned from minor maintenance to a major earthmoving operation. And that practice may have other affects on the beach - and even if it doesn't, nearby changes are quickly attributed to the most obvious culprit, which is the county guy in the backhoe. It's harder for people to see the bigger picture, which is a complex system undergoing big changes over relatively long periods of time.
There are other complications, too. There's an outfall (which substitutes for the historic tidal inlet) right next to the ramp that at times is completely buried, but at others flows vigorously, rearranging the beach in the same location as the boat ramp. And then half a mile downdrift (north), there's an old pier that may have continuing effects on the beach both up and down drift.
This would make a great example of the problems with building on sand spits, except for the fact that there are other even better examples nearby. Sunlight Beach comes to mind, but so do Maxwelton, Columbia Beach, and Bell's Beach!
A series of photos illustrating the role of overwash in shaping barrier beaches is a standard element in many of my beach talks and one of my favorite examples is Perego's Lagoon on the west side of Whidbey Island. This Saturday I was up on Whidbey (at Sound Waters) and just before my presentation, someone mentioned that waves had recently breached that spit.
So I skipped out on the third session of the day and drove up to Ebey's Landing to check it out. Sure enough, there was a small breach in the berm crest near the south end and a fresh deposit of sand, gravel, and logs in the lagoon. This looks pretty small compared to some of the older, preserved ones nearby, but still very neat to visit before it patches itself back together (which it will probably do pretty quickly).
AERIAL VIEW
Although I don't know for sure, this likely occurred on December 20th, when a strong wind storm coincided with a high tide and a strong surge. There have been reports, and numerous videos, showing the fierceness of that storm, particularly in northern Puget Sound (Birch Bay got hit really bad).
Here are some previous posts from Perego's, some of which show the earlier overwash fans quite a bit better:
Gravel Beach: Perego's Lagoon
Hidden Beach is hard to find. It's tucked in at the base of a high bluff along Saratoga Passage, at the bottom of a steep road that most folks on the main road don't even know exists. Even when you get to it, the beach is still sort of hard to find. It's buried beneath rocks and fill and old concrete and the occasional auto part. A row of piles out on the beach testifies to the original intentions, but this stretch at the north end was never developed, or if it was, little is left of it now.
AERIAL VIEW
Years (decades) ago, I came down here and walked north to check out the wonderful high fluted till bluffs and some large glacial boulders just offshore. I don't think I've been back since, although I often look across at this shoreline from Cama Beach (on Camano Island), just across the water.
The Hidden Beach community to the south is a great example of a type of development that is pretty common on Whidbey Island (elsewhere, too). Or was - most of the initial earthwork occurred in the 1950s and 1960s - you could never fill on top of the shoreline like this today.
Here's what it looks like on Ecology's Coastal Atlas: Aerial Photos
I've heard different versions of how these places were built, but basically the developer built a seawall out on the beach and then filled behind the bulkhead, burying the beach and creating building lots where logs once floated and fish once swam. They added just enough fill to raise the building sites above (most of) the highest tides. The fill material typically came from the bluff itself. Sometimes they used equipment, sometimes they used hoses, and sometimes they used dynamite.
The result was small, isolated beach communities that were wonderful escapes in the summer but that were squeezed beneath landslides from above and storm waves from the Sound in the winter. And an access road that would become impassable just when folks most needed to get out.
A year and half ago, a 400' creosote timber bulkhead was removed from this beach (Waterman: May 2016). Restoration projects are always difficult and complex, but this one was conceptually pretty simple. Remove the old bulkhead and let nature take over. Which it (she?) is. Erosion, slides, falling trees. Fresh sand on the beach. You can still tell that something was done, but in a couple of years this shoreline will look like much as it did 500 years ago (some of my friends among the forest elves may disagree). The active slope will always make the trail a little muddy and challenging (it's currently closed), but with a little ongoing upkeep, it seems like folks should be able to get down and enjoy the beach (Waterman Preserve)
.
AERIAL VIEW
I'm sure I've noted before how difficult it is to describe the typical Puget Sound beach - what makes them all so special is that they are all so different. But a sand and gravel beach at the base of an eroding bluff, drift logs caught up among the fallen trees, eelgrass draped from the overhanging branches, truly gigantic pieces of wood, and occasional glimpses of human history - that's pretty much it. Of course, there's also early morning sunshine, views across the water of snow-capped volcanoes, and recognition that while humans are amazing builders, they also have the amazing capacity to see the value in unbuilding things now and then.
I've been slipping. Maybe I was thinking I was going to write something longer, but just didn't seem to get to it. It's summer, after all. But I've had a bunch of pictures from Double Bluff in the queue for more than a month and if I don't do something with them, they'll sit for another month. So I'll post the photos with minimal commentary, hoping it will allow me to move on.
Double Bluff is the distinct light colored cliff you see when you look north up the Sound from the Edmonds ferry. It is a long, straight stretch of high bluffs, oriented perpendicular to the maximum fetch. One of several notable "swash-aligned" bluffs on the Sound.
It's a cross-section of older interglacial fluvial sediments (Whidbey formation) overlain by Vashon advance outwash and till (though that stuff is high above the beach). There's a lot of variability in the sediments - not a terribly simple layer cake. And there are some fascinating deformation features that always capture attention and cause arguments among geologists.
AERIAL VIEW
You often see big chunks of peat on the beach - coming out of the Whidbey, so they date back a glacial cycle or two. There's a big boulder at the east end. Chuckanut, apparently, with a big fossil palm frond on top (something like that, I'm no botanist). Started near the equator, traveled to Bellingham, then got delivered to south Whidbey 18,000 years ago. Give or take a few thousand years. It's not going anywhere right now.
Most of the sand that erodes from the spectacular bluffs south of Maxwelton (March 2010) works its way north past Mackie Park (previous post), then years or decades later, it arrives at the head of Useless Bay, where it spends time on the large spit at Sunlight Beach, before ending up in bars at the mouth of Deer Lagoon.
AERIAL VIEW
Sunlight Beach is a long, complicated story. And perhaps one that regularly repeats itself. Sediment for Sunlight Beach comes from the south, but the supply of this material (mainly sand) appears to be metered by a smaller spit just to the south (often referred to locally as Henny's Spit). This southern spit gradually grows, forming a small lagoon and gradually pressing its outlet into Sunlight Beach, which causes erosion and consternation -- in part because the spit berm is the location of the dike that was built a hundred years ago to keep salt water from flooding into the old marsh behind the spit and in part because since then, a large number of people have built their waterfront homes on that same berm/dike.
When the small spit is building, it may starve Sunlight Beach of sand and the beach narrows - thus a diverse assortment of bulkheads, rock revetments, and timber groins. These were visible in the early 1970s and again in the mid-1990s. And are reappearing again.
But if the small spit breaks up, for example, if a new channel opens up farther south, the remaining portion of the spit welds itself onto Sunlight Beach, creating a decade of wide beaches for the residents. Folks who moved in five years ago may not even know that they have riprap and groins down below that wonderful beach,
But then this plug of sediment moves on through, its leading edge moving towards Deer Lagoon and its trailing edge leaving rapid erosion and re-exposed structures farther east. That's what's been happening the last few years.
This is probably a difficult story to follow - it would benefit from a more systematic narrative and a lot of historic maps and pictures. Meanwhile, check out the historic images if you have Google Earth.
I was involved in a number of shoreline issues on Sunlight Beach in the 1990s. For me, early in my beach career, this place was a great case study in the complex dynamics of beaches and spits. It was also clear that while some problems might fade for a few years, most would eventually come back!
The spit at Maxwelton continues to grow northward, but local rumors (and recent Google photos) suggest the south end is beginning to erode.
AERIAL VIEW
The Maxwelton community is built on an earlier spit and the marshy lagoon that lay between it and the bluff. But in the early 2000s, a new spit began to emerge offshore near the south end and then gradually extended itself along the shore. The tip passed the Mackie Park boat ramp around 2007 and has kept going. It's preceded by a zone of erosion, presumably because the growth of the spit starves the downdrift beach (erosion is also related to the migration of the mouth of the inlet, which tends to be pressed close to shore, as well as to changes in wave patterns around the end of the spit).
Here are some earlier posts from Maxwelton. Although I've visited this site many times, apparently I haven't posted anything since 2010!
March 2007
April 2009
March 2010
In the last couple of years, the spit has slowly stretched northward and this past winter it raised concerns for some property owners near it's advancing tip.
Of course, the interesting question is what happens next. Will the spit continue to extend, shifting problems still farther north? The T-Sheet from the 1870s shows an extremely long, narrow spit extending another mile north, well past the old mouth of the Maxwelton estuary (now in a tide gate). Or, will the updrift (southern) end erode until waves breach the lagoon, creating a new inlet and perhaps leading to closure of the current north inlet. Which might in turn lead to major changes in the spit itself.
This winter, some very high tides filled the lagoon in front of the park with logs. They're probably not going anywhere as long as the spit itself remains.
