Rethinking Shoreline Armoring

Given the many occurances of slumping of coastal bluffs in Metchoisn over the past winter, this series provides an excellent analysis reflecting on the effects of human interference in natural shoreline processes and the mitigation efforts being made in Puget Sound.

Rethinking shoreline armoring

Before and after view of shoreline restoration project at Penrose Point State Park in Pierce County, WA.

Salish Sea Currents presents an in-depth series focusing on shoreline armoring in the Puget Sound region. Close to a third of Puget Sound’s shoreline is classified as armored with bulkheads and other structures meant to hold back storm surge and erosion. But new studies reveal the often significant toll this is taking on the environment. To be notified of new Salish Sea Currents stories, subscribe to the Puget Sound Institute eNews.

Taylor Beach Land Slides in February 2016

This past week we have had a few days of extra heavy rainfall in Metchosin and  consequently the hazard land slopes of the Development Permit Area along the Taylor Beach bluff have certainly met the designation.  On the South end of the bluffs alone, at least ten new slides have left large gaps on the cliff and have deposited piles of vegetation on the beach. Residents on the top of the bluff are continuously at risk of losing property so development of any new structures or vegetation removal is inadvisable.

The following pictures were taken starting from the south end of the cliff toward the first corner heading North.

 

 

 

Surf’s Up !

Since the 25th of November, we have had 5 inches of precipitation and in the last two weeks an unusual number of South-Easterly storms providing great action at Taylor beach in front of the farm, especially at high tide. The view starts by looking towards William Head prison and ends with a view of Victoria in the distance

 

 

Cliff failure on Taylor Beach

In the last 24 hours, a large slump has occurred on the Taylor Beach cliff. This is located just at the north end of the beach component. The properties along the top of the cliff have for several years experienced various human impacts which have likely contributed to this erosion.

  • Disposal of yard waste over the bank.
  • Removal of trees on properties to create better viewscapes
  • Building too close to an erosional bank feature
  • Topping of trees on the cliff face to improve views
2015-01-08taylorslump

Taylor Beach slump. G. Fletcher photo.

This Cliff is all included in the Hazard lands DPA, and it is also a naturally occurring geological erosional feature which, unfortunately poor enforcement over the years has contributed to this problem.

There remains further evidence of slipping in the separated section showing a grey clay bank along a wider stretch of this bank so we can anticipate more similar events.

Currently a large deposit of soil, broken mature alders and debris remains on the beach. The next big storm from the East at a high tide will clear this out causing increased sedimentation along the inter and sub-tidal areas off shore.  There us a thriving community of organisms on this shore so an impact on those populations is predicted. .

2015-01-08taylorslump3 copy

Taylor Beach erosion- G. Fletcher photo.

2015-01-07 cliffslide

Taylor Beach erosion with tangle of alders. G. Fletcher photo.

 

Post North-easterly Storm on Weir’s beach, Dec 2014

During the past few weeks, we have experienced several storms out of the north east at high tide. These images were taken to document some of the on-going problems from the extensive rip-rapping and seawall construction on that beach. See this page for summer 2013 images for comparison.

2014-12-26 weirserosion2

The solid sea-wall built only last year will lead to increased scouring and removal of sand. Unfortunately it will not only affect the crown land property in front of the wall, but the crown land foreshore adjacent to this property .

 

2014-12-26 weirserosin

Recent storms have dislodged many of the boulders near the south end of the beach. Note the rubble foreground which was previously sand beach.

2014-12-26 controlgate

This concrete control gate was built many years ago to control flooding into a lagoon. The rip-rap boulders around it have been disturbed by wave action.

2014-12-26 weirsbeachwidth

Site A= south end of the beach-sand eroded from base of rip-pap wall. Site B The border of where the rip-rap ends and the natural beach (going northward,) begins. C=the widened sand beach area backed by the natural beach. Scouring of the sand does not occur as it does further south on the beach.

2014-12-26 natural-portion

The berm on the North end of Weir’s beach is in a more natural state with logs and debris thrown up by storms. The and natural beach vegetation and debris absorbs the impact of the ocean energy and no scouring of the beach sand has occurred. This will lead to long-term beach stability and erosion-resistance.

See other posts and references on hardening of the shorelines by clicking on links below.
See this file on early pictures of Weir’s beach

Coastal erosion as a sediment source – implications for shoreline management

Puget Sound Feeder Bluffs: Coastal erosion as a sediment source and its implications for shoreline management Shipman et al 2014 .
See the PDF: pugetsoundhardening1406016

feederbluffreport

This report examines the role of eroding bluffs as a source of sediment for Puget Sound beaches and includes a review of related geology and coastal processes. It summarizes recent mapping of feeder bluffs and examines ways in which this information can be used to improve shoreline management.

This report is one part of a larger project on Puget Sound feeder bluffs that also includes maps and a series of web pages that cover much of the material in this report. The project was funded by EPA and the WA Department of Fish and Wildlife. Hugh Shipman and colleagues  published this  important report on feeder bluffs processes and management. Coastal Watershed Index of Port Angeles has been working on the complex and critical topic of feeder bluff management for over a decade. One of their biggest challenges is imparting the critical and unique elements of feeder bluff function and management (including the reality that there are no ‘soft armoring’ techniques appropriate for this land form ). This report provides scientific and management focus specifically to feeder bluffs of the Salish Sea- it’s long overdue.

 

feederbluffmaps

 

Part 2 is of the maps of feeder bluffs of Puget sound:

 

 

 

Accessed Nov 4, 2014 at :
https://fortress.wa.gov/ecy/publications/SummaryPages
Maps:
https://fortress.wa.gov/ecy/publications/publications/1406016part2.pdf/1406016.html.

See More on Feeder Bluff mapping:

 

 

 

 

 

Publication: Protecting Your Communities Coastal Assets

Local Leadership in marine planning: Local governments on B.C.’s Coast have the power to protect the ecosystems we depend on.

This report describes easily accessible resources local governments can use to maintain aquatic Ecosystem Value and Productivity, including maps and tools to guide decisions and bylaws regarding management of activities on land , and in intertidal and sub-tidal zones.

protectingassetsicon

 

Download .pdf from this website

or

Originally available here:
powerinhands

Why Sand Is Disappearing ( from beaches)

beachlooknorth

The heavily impacted Weir’s Beach which has experienced considerable sand loss in recent years largely due to bad management of the shoreline.

This article highlights a good example how human interference ( anthropogenic) in a number of ways can result in the loss of Natural Capital and long term sustainability . 

The beaches of Metchosin are not immune  to the forces of Climate change and uninformed decisions of upland landowners and municipal governments which refuse to enact rigid Shoreline Development Bylaws. 

This has been quoted  from: The NYT Opinion Pages    NOV. 4, 2014

” BERKELEY, Calif. — To those of us who visit beaches only in summer, they seem as permanent a part of our natural heritage as the Rocky Mountains and the Great Lakes. But shore dwellers know differently. Beaches are the most transitory of landscapes, and sand beaches the most vulnerable of all. During big storms, especially in winter, they can simply vanish, only to magically reappear in time for the summer season.

It could once be said that “a beach is a place where sand stops to rest for a moment before resuming its journey to somewhere else,” as the naturalist D. W. Bennett wrote in the book “Living With the New Jersey Shore.” Sand moved along the shore and from beach to sea bottom and back again, forming shorelines and barrier islands that until recently were able to repair themselves on a regular basis, producing the illusion of permanence.

Today, however, 75 to 90 percent of the world’s natural sand beaches are disappearing, due partly to rising sea levels and increased storm action, but also to massive erosion caused by the human development of shores. Many low-lying barrier islands are already submerged.

Yet the extent of this global crisis is obscured because so-called beach nourishment projects attempt to hold sand in place and repair the damage by the time summer people return, creating the illusion of an eternal shore.

Before next summer, endless lines of dump trucks will have filled in bare spots and restored dunes. Virginia Beach alone has been restored more than 50 times. In recent decades, East Coast barrier islands have used 23 million loads of sand, much of it mined inland and the rest dredged from coastal waters — a practice that disturbs the sea bottom, creating turbidity that kills coral beds and damages spawning grounds, which hurts inshore fisheries.

The sand and gravel business is now growing faster than the economy as a whole. In the United States, the market for mined sand has become a billion-dollar annual business, growing at 10 percent a year since 2008. Interior mining operations use huge machines working in open pits to dig down under the earth’s surface to get sand left behind by ancient glaciers. But as demand has risen — and the damming of rivers has held back the flow of sand from mountainous interiors — natural sources of sand have been shrinking.

One might think that desert sand would be a ready substitute, but its grains are finer and smoother; they don’t adhere to rougher sand grains, and tend to blow away. As a result, the desert state of Dubai brings sand for its beaches all the way from Australia.

And now there is a global beach-quality sand shortage, caused by the industries that have come to rely on it. Sand is vital to the manufacturing of abrasives, glass, plastics, microchips and even toothpaste, and, most recently, to the process of hydraulic fracturing. The quality of silicate sand found in the northern Midwest has produced what is being called a “sand rush” there, more than doubling regional sand pit mining since 2009.

But the greatest industrial consumer of all is the concrete industry. Sand from Port Washington on Long Island — 140 million cubic yards of it — built the tunnels and sidewalks of Manhattan from the 1880s onward. Concrete still takes 80 percent of all that mining can deliver. Apart from water and air, sand is the natural element most in demand around the world, a situation that puts the preservation of beaches and their flora and fauna in great danger. Today, a branch of Cemex, one of the world’s largest cement suppliers, is still busy on the shores of Monterey Bay in California, where its operations endanger several protected species.

The huge sand mining operations emerging worldwide, many of them illegal, are happening out of sight and out of mind, as far as the developed world is concerned. But in India, where the government has stepped in to limit sand mining along its shores, illegal mining operations by what is now referred to as the “sand mafia” defy these regulations. In Sierra Leone, poor villagers are encouraged to sell off their sand to illegal operations, ruining their own shores for fishing. Some Indonesian sand islands have been devastated by sand mining.

It is time for us to understand where sand comes from and where it is going. Sand was once locked up in mountains and it took eons of erosion before it was released into rivers and made its way to the sea. As Rachel Carson wrote in 1958, “in every curving beach, in every grain of sand, there is a story of the earth.” Now those grains are sequestered yet again — often in the very concrete sea walls that contribute to beach erosion.

We need to stop taking sand for granted and think of it as an endangered natural resource. Glass and concrete can be recycled back into sand, but there will never be enough to meet the demand of every resort. So we need better conservation plans for shore and coastal areas. Beach replenishment — the mining and trucking and dredging of sand to meet tourist expectations — must be evaluated on a case-by-case basis, with environmental considerations taking top priority. Only this will ensure that the story of the earth will still have subsequent chapters told in grains of sand.

New Publication on Shoreline Erosion Control out of Washington State

I attended the Salish Sea Ecosystem Conference in Seattle several weeks ago and one of the sessions I attended was delivered by the presenter of the following report.
In  Puget Sound there is no hesitation in bsing very specific on what needs to be done about controlling the impact of humans on the shoreline as they have a long history of making a real mess of many kilometers of shoreline.

http://wdfw.wa.gov/publications/01583/