Friday, August 11, 2017

First Beach


First Beach, which is also simply called English Bay Beach, is the largest of the sculpted beaches along Vancouver's English Bay. As with all these beaches, it faces directly into the largest waves, otherwise the beach would leak out at one end or the other.


AERIAL VIEW

Saturday afternoon is pretty much just a sunny day at the beach and the tide rising over the low tide terrace is warm enough to swim in - and many folks do. By late afternoon, the crowds thicken. I do my best to estimate where the water level will be when the fireworks start, so we can be in the right place at 10PM, and the other several hundred thousand people are behind us, not in front of us.

By early Sunday morning, the beach is clean, empty, and groomed (for more on grooming, see English Bay: August 2006).





False Creek


Just a few shots of the edge of False Creek - a wonderful shoreline, albeit not quite the marshy estuary it once was. There's really not enough wave action to create beaches in here, even if the configuration and the profiles were more amenable, so the result is an interesting assortment of engineering treatments.

AERIAL VIEW

Here are some links back to some earlier False Creek posts:
Creekside: October 2011
Yaletown: October 2011
False Creek: August 2010



English Bay


I've posted many times about many different beaches on English Bay - I suppose they are my favorite urban beaches, we visit them regularly, and I always take too many pictures. Here are a few, from the last weekend in July.

Most of the photos are of Sunset Beach, on the north side of the inner portion of the bay. Including the little beach that peters out up against the Burrard Street Bridge and the entrance to False Creek.

The last photo is Hadden Park's Dog Beach, just across the water in Kitsilano. It also appears in Kitsilano: April 2016.

AERIAL VIEW



Gravel Beach: Vancouver (lots of beaches, lots of posts)

I'll follow up (I think) with some photos of First Beach, also on English Bay, and several non-beaches on False Creek.

Thursday, August 10, 2017

Double Bluff


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.







Monday, June 26, 2017

Fort Worden


It seems like all my recent posts have been from the Strait - the Miller Peninsula, the Elwha, and now, the northeastern corner of the Quimper Peninsula. But recent is relative. This Saturday excursion to Fort Worden was back on the 10th, but if you've been paying attention the last ten years, you know that sometimes my posts run a bit late. Always in order, but often delayed. If you've been following along, you also know that my photos and my narrative don't always align terribly well.

The beach walk was part of a grand loop around the north side of Fort Worden. We began with low tide on the north side of Point Wilson, where we could look at the curiously distinct and squared off boulder field and the wood debris sticking out of the beach along its western edge. Bulldozers, faults, or coastal retreat across a back-barrier lagoon that used to sit below a steep forested slope? And how does that relate to the big divot in the bluff that looks so much like a singular landslide, but which doesn't explain why the coastline itself jogs as well.



AERIAL VIEW

The beach along North Beach is great, with sand, gravel, big boulders, and occasionally glimpses of the underlying platform. But it's somewhat overshadowed - figuratively and literally - by the bluffs themselves. At the eastern end, it looks like Whidbey Formation, including a surprisingly continuous peat layer a few feet above beach level, overlain by Vashon stuff. But as you move west, the layer cake has been disturbed and late glacial Everson (so I'm told) appears - mainly gravels, but with some amazing ripups of the underlying glacial material. Something pretty exciting happened here during the waning stages of the last glaciation - it took a lot of water moving very fast to leave that kind of deposit (and it's much better exposed than my last visit). Is this evidence of Puget Sound (Lake Russell?) spilling out around the edge of the retreating ice? Or something else.

The walk back along the top edge of the bluff was a lesson in periodically relocated fence lines on the bluff (always to the south) and big artillery (the big guns are all gone, but the batteries and the views remain).


Credit for the day goes to Michael and Kitty and Leslie and all the other folks at:
The Jefferson Land Trust Geology Group

Thursday, June 01, 2017

Valley Creek



The mouth of Valley Creek was opened up a long time ago (10-15 years?), creating a small estuary out of once had been industrial fill, that I suppose once was a beach and a small estuary. In the last couple of years, the city completed the next phase of the park, which consists of two engineered beaches on the shoreline immediately east of the creek.

AERIAL VIEW

There have been a significant number of pocket beaches built on urban shorelines in the region, but this is one of very few that have been built as a pair. The idea has been proposed, but usually gets nixed due to costs and some basic geometric challenges. Constructed pocket beaches need to be oriented into the waves. And they need to be confined - either by existing promontories (usually old fill in urban areas) or groins.

This poses problems when a pair of beaches need to be oriented obliquely to the overall trend of the shoreline. The groin that separates them must often be a major feature, with a large difference in elevation from one side to the other (see aerial). This means a lot of rock is exposed (in this case, on the east end of the western beach). This in turn probably makes it harder to keep the higher beach from leaking through the rock structure - there was a little evidence that some of this might have happened here.

This site still seems pretty bare. It will be nice to see it with more vegetation, more landscape elements, and a few more amenities. it would be nice if we could incorporate more sand into these steep pebble beaches, but that's tough when you want stuff to stay put and your geometry requires the steep beach face provided by permeable, well-sorted gravel.


Here are links to some other constructed pocket beaches (some are very much the same, some are very much not):

Boulevard Park: 2014 (Bellingham)
Sunset Beach: 2016 (Vancouver)
Brackett's Landing: 2016 (Edmonds)
Sculpture Park: 2017 (Seattle)
Ross Bay: 2013 (Victoria)
Maumee State Park: 2010 (Ohio)
McKinley Beach: 2016 (Milwaukee)

Wednesday, May 31, 2017

Dry Creek



The beach begins at the Elwha and ends at the tip of Ediz Hook -- at least in a simple, first-order conveyor belt of gravel, kind of way -- which is probably a little too simple. The central portion, between the eastern edge of the historic delta and the base of Ediz Hook, consists of 5 km of steep bluff. Dry Creek is in the middle.

AERIAL VIEW

From the Elwha to the ravine at aptly named Dry Creek, the bluffs are unarmored and the beach is wild. From Dry Creek to Port Angeles, things are a mess. The waterline was buried in the beach below the bluffs, but has subsequently been exposed by erosion and is now a 3km reach of riprap and sheet pile, below bluffs that continue to erode, albeit slower than they once did. Maybe it's fortunate that this beach is hard to access and most folks in town don't realize how bad it looks. Unfortunately, I don't have any pictures of this stretch to share in this post. I'll come back sometime.

The real highlight of this stretch, however, is the landfill immediately east of Dry Creek. The big wall goes back to 2006 or so and we can argue whether it's better or worse than the old refrigerators eroding out of the bank. But after the wall was built, folks discovered that maybe the eastern part of the landfill was at risk, too. The closest cell was a deep pit immediately behind the high eroding bluff. The good news is that they could have rocked the whole thing, but instead made the decision to move the vulnerable garbage out and move it landward. But in the process, they've left a remarkably bizarre landscape! And over time, this stretch will only get weirder.


There are a lot of photos of Dry Creek, the Elwha, and Ediz Hook in the blog. Searching within the blog on any of these terms should bring up earlier posts (although they sometimes bring up unexpected posts as well). Unfortunately, there are no pictures of the water line or of the landfill when the garbage was still slumping onto the beach.




East of the Elwha


As noted in the previous post, the rapid growth of the Elwha Delta following dam removal appears to have slowed. But during the past year or two, this eastern beach has grown rapidly as a result of a huge influx of sandy material. In places the beach has grown outward many tens of meters - with a steep cobble beach being replaced by a much broader sandier one.

AERIAL VIEW

Beach Lake refers to the lagoon, probably associated with an old channel of the river, that had been trapped behind the historic berm but that had been narrowed and breached by the rapidly retreating beach. Decades ago, a significant portion of this reach had been armored and this riprap was left in a broad arc on the beach face as the shoreline continued to erode.There was also at least one groin-like structure. All of these were recently removed by the Coastal Watersheds Institute and this, combined with the fresh sediment from the delta, has resulted in a much renewed beach.

The upland structures are slated to be removed. The plan is that this will become a public access - to a wonderful stretch of beach and to a highly regarded local surf break.

There is still one last stretch of rock and decayed timber bulkhead at the very eastern edge of the delta. As the beach has retreated, this rock has projected farther and farther onto the beach and looks like it may be exacerbating erosion at its eastern end. If it could be removed, the beach would be completely unarmored and unimpeded from the river mouth all the way to the Dry Creek (next post).



Elwha Delta


This is the first of two posts from the mouth of the Elwha. This one is built around photos taken near the tip - on both sides of the river mouth. The next post will be from a little farther east.

The river is currently flowing out into Freshwater Bay on the western side of the delta, although the linked imagery from Google Earth currently doesn't reflect this.

AERIAL VIEW

The broad crescent-shaped beach on the west side of the delta seems much simpler than the messy beach on the eastern side of the delta (next post). It has continued to accrete into Freshwater Bay and appears to be doing so in a fairly uniform fashion along its length. I guess this is how I might expect a swash-aligned beach to respond to additional sediment. But the beach on the east side is progressing much less cleanly - perhaps because of its drift alignment and the uneven transfer of sediment along its length. I say perhaps - I often say perhaps - to clarify that this is some speculation based on fairly limited observations. There are others watching this much more carefully and hopefully they will be able to put together a more rigorous story (and maybe a different story) in time.

The Elwha Dam was gone by mid-2012, the Glines Canyon Dam, farther upriver, was out in 2014. Fresh sediment reached the shore very quickly after the lower dam was removed and the new delta built out rapidly for at least four years. That process seems to have now slowed as the initial plugs of sediment flushed through and the reservoir bottoms have begun to stabilize.

The slowing (at least from what I can see) of delta growth provides an opportunity for coastal processes to take over. During the first few years, the beach east of the delta continued to retreat, despite the huge accretion at the river mouth. But in the last year or two, a huge amount of sand has moved east, perhaps as the front of the expanded delta has begun to erode.

Previous posts about the Elwha Delta