Tuesday, July 19, 2016

Kukutali


I'm just trying to catch up. And this post will do it, although it's already a month old. These photos are from a visit on Father's Day with M - the first time I'd been here in a long time and the first time since the new entrance had been improved.

AERIAL VIEW

The Kukutali Preserve (Kiket Island) is co-managed by the Swinomish Tribe and Washington State Parks. And it's a wonderful place for a short hike on a beautiful day. Two tombolos, each side of which is a pocket beach, along with a bunch of smaller beaches scattered along the rocky shore. The tide was low enough so we could walk out to the tip of Flagstaff Island (the upland portion is off limits - this kind of meadow is both fragile and scarce).

For a lot more photos of Kukutali - and a lot more attention to the flora and fauna - check out Dave's Fidalgo Island Crossings blog.


Edmonds


Early morning in Edmonds, waiting for a ferry (more than a month ago). This beach was once the spit that sheltered the north end of the Edmonds Marsh, but that was before sawmills, the railroad, the filling of the marsh, and construction of the marina. Now it's a series of pocket beaches, largely disconnected from one another by structures that extend offshore such as the breakwater and ferry terminal.

AERIAL VIEW

But Edmonds has managed to keep its beaches, and better yet, managed to make them the centerpieces of its public waterfront. Brackett's Landing North, north of the ferry, is a Wolf Bauer project from the 1980s, although the city did some additional work on the backshore, the bulkhead and the walkway following a big storm in the mid-1990s.

Edmonds: February 2014
Brackett's Landing North: April 2009
Edmonds: April 2009


Monday, July 18, 2016

Sunlight Beach




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!



Sunday, July 17, 2016

Maxwelton


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.

Monday, July 11, 2016

Glendale


Glendale Creek is typical of many small streams on Puget Sound that drop quickly through a steep-sided ravine before reaching the beach. The topography suggests that there may not have ever been much of an estuary, but it's likely that the stream mouth was originally deflected north by a spit (drift here is unambiguously from south to north). Building on the beach, and the placement of the stream into a pipe, greatly reduced the stream's freedom to wander and the whatever spit there was became history.


The small community of Glendale is built at the mouth of the valley and periodically gets flushed out by a gully washer (Glendale: 2009). It's pretty much like building on an alluvial fan at the mouth of a canyon - location has consequences.

The Whidbey Camano Land Trust has recently acquired property here at the beach, just south of the stream mouth. I don't know what the plans are for the site, but it seems like a wonderful opportunity to reconnect the beach with it's backshore. That won't restore the original stream mouth or the spit, but it provides access to a wonderful spot on the south Whidbey shoreline. 





Sunday, July 10, 2016

Skyline


I'm playing catch up, so this post dates back to late May.

I posted from here a few years ago and mentioned wanting to see how it weathered over time.
Skyline: November 2012

AERIAL VIEW

This project, which extends about 1000' along the shore, is a complex crib consisting of stacked and interlocking timbers, reinforced with steel cables. It's relatively steep - definitely a revetment, not a beach! While it's easy to see how dirt would get eroded from behind the structure, it's more difficult to see how normal beach building processes (the movement of sediment up the profile by waves) can maintain or rebuild the berm. Loss of sediment has been remedied recently with the addition of small rock (angular, not gravel or cobble) in the eroded areas behind the logs.

The most vulnerable segment of this project is where the shoreline bends, creating a convex seaward curve - a small headland of sorts. This likely results in a steeper profile, more wave action, and a natural tendency for sediment to be moved away from the spot over time.  This is in contrast to the concave seaward beach west of the project, where a small pocket beach is accumulating material (probably material eroded from the headland just mentioned).

This small pocket is at the location of the original tidal inlet, which was relocated to the east end of the spit when this area was (re)developed.


Thursday, May 12, 2016

Deception Pass



I see this beach every time I drive across the Deception Pass bridge (southbound, at least). I see this beach in dozens of pictures I've taken from the bridge (for example: Deception Pass: May 2013). I've seen it numerous times from the rocky promontory where West Beach turns the corner and becomes North Beach. But I don't know if I've actually visited this beach since I started working on beaches more than 25 years ago!

So late on a Friday afternoon two weeks ago, I decided I could delay the trip home for an hour or two. It was one of the best decisions I've made in a long time.

AERIAL VIEW



North Beach is the terminus of the West Beach drift cell. Although I suspect much of the sediment that drifts north along the west side of the Whidbey Island is lost offshore to deep water as it rounds the corner, some gets through. Or at least enough has gotten through in the past that the beach has been able to form and even build out, filling indentations in this originally steep and irregular rocky shoreline. This is a complex area, with strong currents and deep water just offshore, which undoubtedly confuses any simple picture of this beach's behavior. 

There's a neat animation of the West Beach drift cell at the new Shore Friendly website:
Shore Friendly: West Whidbey
(it's worth checking out the rest of the website, too)


I'm often asked about my favorite beach on the Salish Sea. I always struggle with this question (it's sort of like asking me my favorite color or my favorite restaurant), but as soon as I walked down the trail I realized I'd found an answer to that question. It may not be my only favorite beach, but it's the perfect answer the next time I'm asked. It's got everything - rocky headlands, beaches, an undeveloped backshore, fast-moving water, big trees, public ownership, an easy trail, and a beautiful bridge.


Macs Cove - the eastern end of North Beach







Oak Harbor


The low area that connects most of Oak Harbor to Forbes and Maylor Points may have begun as a tombolo - with a low beach connecting the higher ground at both ends. I don't know what its pre-war history, but during World War II the Navy filled much of this area to create a large seaplane base out of which they flew PBY Catalinas.

AERIAL VIEW

Oak Harbor's shoreline configuration seems like it lends itself to beaches (heck, that's what used to be here). There are already some nice ones on the west side of town. Maybe there are also some opportunities here at the east end to enhance beaches in front of the riprap (or replace the riprap with beaches), including this section around the marina. The wave energy is low, so the size of the sediment would be fairly small (so it can still move). I could picture a high tide beach much of the way from downtown around to Maylor Point, where the Navy has already done some beach restoration work in the last few years (a future visit, a future post). With any luck, other folks are already planning this!



Wednesday, May 11, 2016

Maynard's Beach


Two weeks ago, I got a chance to revisit this restoration site on Discovery Bay (Previous post: Maynard's Lagoon: January 2015). It's right off of U.S. 101, just past the old railroad cars where, at least in the past, you could get an ice cream cone on the way back from the Peninsula. This is actually just one of several recent restoration projects at the head of the bay - all carried out by NOSC.

The configuration of the site was largely shaped by the railroad and the old mill. The mill is all gone, as are the tracks, but the railroad grade itself now helps create a series of lagoons (pocket estuaries, as we often call them here). The result is a fairly natural interpretation of a largely artificial shoreline.

In my earlier post, I had suggested that the tracks might have followed a longer spit across the mouth of the main lagoon, but I realize that the remnant spit at the northeast end of the lagoon (on the bayside of the railroad causeway) is probably all there was.

AERIAL VIEW

There's not much wave action here and it may take a while for the beach to sort itself out, but the vegetation is beginning to take off. A large portion of the beach is already sprouting new salicornia (pickle weed), foreshadowing its future as a marsh as much as a beach. This site has a little of everything - a low energy beach, fringing marshes, a stream, multiple lagoons, and upland forest. It will be fun to watch it evolve in the coming years.



Salsbury Point


In the fall of 1995, Kitsap County Parks removed the old riprap and nourished the beach. And it's still doing remarkably well.

It's a difficult site - the lagoon was filled, the beach pushed out, and the coastal regime altered because of the boat ramps and because the floating bridge has cut off much of the southerly wave action (which would have continued to deliver sediment). The original plan was just to rebuild a nicer rock bulkhead, but a habitat biologist pushed back, suggesting something softer. And County Parks staff were willing to listen. A geologist with the state (much younger then) helped them sketch out some ideas and cross-sections, based on experience with some of Wolf Bauer's designs.

Beach east of the boat ramps
Although I was pretty confident the project would work, I never would have expected it to go 20 years without a little assistance. The underlying erosion problem remains and the beach has gradually retreated into the backshore created in 1995. The backshore is a little too high, so it doesn't get overtopped, and therefore supports upland vegetation better than beach grass. An old drain pipe has gradually been exposed and dribbles rusty water onto the beach.

Healthy beach at south end of park
Previous post:  Salsbury Point: 2013

I think some adaptive management is due. Before someone gets surprised and does something dumb. I understand there is talk of doing some work on the boat ramp(s) - maybe that will be a chance to look at some options.

AERIAL VIEW

Of course, there's still a difficult stretch between the main park and the ramp - I think it's where electric cables head out under the canal. It's oriented obliquely to the waves and has no sediment - which presents a real challenge.