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The new beach at Weaverling Spit has progressed in three phases, the most recent of which was completed this past fall.
AERIAL VIEW
Each phase was designed a bit differently, reflecting slightly different site conditions, objectives, and perhaps lessons along the way. Of course, I suspect budgets and permit requirements were slightly different on each phase, too. All three involved beach nourishment, combined with planting of the bank/backshore and the use of anchored logs as small sills or groins.
Phase 1, farthest west, is 9(?) years old now and looks great.
Phase 2, in the middle, was done a few years later. The nature of the anchored log sills was different - the root masses were oriented differently and they were placed fairly high compared to the adjacent beach grade.
Phase 3 is still fresh and I assume plantings are planned. The folks who rent out those RV spots probably don't want trees and thick brush, but there are a lot of good options. The berm is much larger, although I suspect this is a function of the backshore being lower here than on the earlier phases.
Note the log placed perpendicular to the beach immediately west of the boat ramp at the easternmost end of the project. I assume this was to limit the movement of the added sediment onto the ramp - which might be expected since the new nourished beach is slightly higher (and there's a slight tendency for eastward drift of material along here anyway). I'll be curious to see how well this works.
There's more on this project at:
CGS: Weaverling Spit
And here's a link to all of my posts from here:
Gravel Beach: Weaverling Spit
I love this little tombolo between Kiket Island and Flagstaff Point, particularly the arcuate fine gravel pocket beach on the north side, which sort of underscores the challenges of simplistic beach classifications. While the overall landform is a tombolo, a type of barrier beach, this particular beach acts in most ways like a pocket beach - not an unusual situation. The one complication might be that under the right conditions, sediment might get carried to this beach by overwash from the south side, slightly confusing the otherwise simple picture of a pocket beach as an isolated sediment cell with negligible import or export of sediment.
The south beach gets more wave action and collects logs (south winds push them onto the berm on high tides). The north beach is more protected and logs don't accumulate, since south winds blow them off the beach (if they ever make it there in the first place).
Visitors are discouraged from tromping across Flagstaff Point in order to protect the vegetation community on the relatively rare rocky bald (I think that's the right name). Around the edges, we could see the Camas coming up and the rock outcrops were covered with sedums.
For shots from previous visits, check out Kukutali 2016 and Kiket Island 2009. And for a nice view of Kukutali from the air, check out the drone footage at:
https://www.youtube.com/watch?v=sDrCZl65kA4'
Bayview is just down the road from the Padilla Bay Reserve and an easy place to check out during a short lunch break. Although I knew there was work planned here, I was never clear just what was going to be done - or even just what problem was to be solved. Not that this site hasn't had problems - the inevitable consequence of it's artificial creation many decades ago, it's rectangular footprint, and it's unnatural projection out into the bay.
AERIAL VIEW
Here's a post from a few years ago - Bayview: January 2012 - which may provide some hints as to the recent work. Previously, two terminal groins and two intermediate groins maintained a nourished beach on the western edge of this rectangular pad of historic fill.
The new project has removed the intermediate groins, enlarged the terminal groins, and added a lot of gravel. The beach at the south end of the site, which never amounted to much, has been significantly enhanced with gravel and logs. And the backshore has been improved with plantings and some effort to manage beach access points.
Overall, it looks pretty good. The end corners, where much extra sediment was placed, will continue to adjust -- and I suspect the additional material was placed with this in mind. We'll keep watching.
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.
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.
This fall the rock revetment between the boat ramp and the pier was removed and that section of beach restored. I've included a picture of that beach at the bottom of this post, but this entry is really about a portion of the same beach another 100-200 meters to the south.
We think the wetland used to be much larger, extending to much of the area now occupied by lawn, but there's still a large marsh behind the beach at the south end of Bowman Bay. It collects runoff from a fairly large area, including Pass Lake up on the main road. It drains through a 12" culvert that exits on the lower beach. This keeps the normal water level of the wetland pretty low.
AERIAL VIEW
But this winter wasn't normal. It was wet. And the wetland was filling faster than it could drain through the pipe. A couple of weeks ago, the water level got so high it flowed over the berm creating a new outlet (or at least re-establishing the old outlet -- the history isn't well known). The trail crosses this spot on a bridge, so presumably there's been some history of a channel or of flow through this area before, although the structure normally seemed more like a boardwalk with hand rails.
As the rains diminish (really, I'm sure they will!), the water in the marsh will fall, and the new channel will dry up. Waves will push gravel into the gap and rebuild the berm across the outlet. But what's interesting is that there has been talk in the last few years of restoring a more natural connection between the wetland and the bay. The conditions of the past couple of weeks actually provide useful hints about how that might work. Maybe there is some simple replumbing that would allow the natural outlet to be the primary outlet, and relegate any pipes to more an overflow feature.
The photo below is of the main beach where the restoration work was done this fall. At the time, I posted about the site (Bowman Bay) and noted the steep scarp that had formed during a big storm that occurred right after the project was completed. This photo shows the scarp remaining, but it has been broken down by foot traffic and the beach in front has built back up, reducing the overall effect. Personally, I think this beach needs a few good high tide storms to cut that upper bank back another 10-15', dropping that big super-elevated log down a couple feet to a more natural position and creating a more natural berm for the dune grass to recolonize.
Another beach restoration project, not far from the last one (Ala Spit). But what an entirely different flavor of beach! Bowman is a pocket beach, facing the Strait. Waves action can be significant, but its incidence is highly constrained by the rocky headlands that frame the entrance of the bay, so we get the typical crescent form of a swash-aligned beach, broken only by the offset against the boat ramp in the middle.
Here's a previous post: Bowman Bay: March 2012
AERIAL VIEW
The old ramp remains and the base of the pier still needed to be protected, but the revetment that had been here for decades was removed a few weeks ago. The basic idea was pretty simple, pull out the rock and excavate the old fill that was too high and too far waterward. On so many of these sites, the erosion problem is entirely one of our making - simply because we pushed the land seaward, crossing a well-defended border - and therefore the solution is simply to pull back to friendlier territory.
Ideally, we want to remove all of the fill and restore the entire profile to something similar to what existed prior to the fill. Any fill or extra elevation that gets left behind will remain subject to unnaturally high rates of erosion and often a scarp will develop.
In this case, there were constraints on how much of the old fill could be removed, which left a higher profile than might have been preferred. That, combined with a strong high tide storm a week after the project was wrapped up, resulted in a significant scarp at the top of the beach. What's missing from the restored beach is the natural berms that mark the unaltered beach north of the boat ramp. With time, this should remedy itself and a broad berm (or series of stepped berms) should form. A few good high tide storms might actually speed this recovery.
When the backshore is left too high, we essentially create a low eroding bluff (Keystone 2012). But natural berms are actually depositional features, so where it's possible, it may be be best to design to a lower profile, and then let nature build the berm where it wants to. This may require more excavation, the placement of more sediment lower on the profile (to supply that berm rebuilding process), and a tolerance of possible overwashing of the initial berm before it gets established.
Conceptually, the restoration at Bowman was pretty simple, but it provides a nice illustration that even simple projects can be difficult. Fortunately, restored beaches are inherently more malleable than what they replaced, so given time and some room, nature can sort things out. It may just take a little longer than we might have hoped.
You would think from many of my recent posts that taking rocks and concrete off of beaches has become pretty popular on Puget Sound!
Late in May, I had a chance to visit Weaverling Spit again. It remains a very accessible and a very nice example of a relatively low energy gravel nourishment project. The second phase of the project - less than two years old - is blending in much better with the adjacent beaches than it did a year ago.
AERIAL VIEW
Dan met up with us and helped us identify the recent spawning in the upper intertidal gravel - although I think even a geologist might have found the eggs on this particular occasion! It's been reassuring to find that smelt and sand lance will spawn on nourished beaches, although there is still some question in my mind about whether this beach really would benefit from more sandy material.
Previous posts: Weaverling Spit
This was a very quick stop at the end of the day (back during the third week of August), but enough time to see how this new beach was sorting itself out. I posted from here last fall, but the weather was awfully bleak and the photos awfully gray. At that time, I said eventually I'd post more, and I guess that't still likely, but it's not now.
Bottom line - very simple (they're never really simple) beach nourishment along the toe of the bank a couple of years ago with a lot of initial reorganization of sediment.
AERIAL VIEW
The site is along the west side of March's Point, north of the old railroad trestle (now Tommy Thompson Trail).
I've fallen way behind - a week in August on Salt Spring and another week driving back and forth from Minnesota in September resulted in some beaches being collected, but not yet stuck in the album. So I'll add them quickly - with abbreviated comments - so I can check this off my list.
This is a neat park on the site of the old Scott Paper mill. The site has been cleaned up. Two new breakwaters were installed to replace the dilapidated timber wall that used to protect this side of the entrance to Cap Sante Marina and to provide shelter for small boats launching from the new pier. There was always a small pocket beach in the cove on the park's north side, but the low tide beach is no longer a tangle of rotting wood and the upper beach is clean gravel, not broken bricks and debris.
AERIAL VIEW
There's a lot more that I'd like to add about this site, but that will have to wait for a future post.
