Focusing on Andersen Inlet erosion risks

I guess there has been a lot of discussion in this blog about changes on the surf beach at Venus Bay but in reality the most significant erosion is going on all along Andersen Inlet.The deeper channels (think of them as a submerged meandering but tidal streams) are snaking back and forth changing position within the inlet progressively widening the inlet and eroding its banks (particularly at Inverloch, on the north eastern side, and around doyle’s road, on the western side. Sand is progressively  moving deeper into the inlet and this hinders the development of mangroves, which are really the only way to slow down eroding the shores. The open “beaches” allow waves to undercut the peat layer of the salt marshes and once compromised like this the salt marshes quickly wash away. Trees offer only slightly more resistance but they soon also succumb to the erosion.

Did the earth move for you?

Last nights earthquake between Moe & Mirboo North, best estimates at the moment a 5.4 Magnitude at 8:54PM, gave the folk in Melbourne a good shaking, but how was it felt at Venus Bay?
Geoscience Australia likes to get reliable first hand accounts of what people felt, as it helps them improve both the assessment and prediction of the effects of earthquakes & damage. If you want to help here is the link,

Having fun …BUT

 
These very noisy mechanized wave runners are obviously have fun, albeit in a high risk way BUT they certainly didn’t impress the other beach one users. The fishermen were muttering about yoboos, the pipi gathers were yabbering about the strong smell of the spilt fuel and the tradition board riders shaking their heads in despair, What I notice is their wasn’t a single bird to be seen anywhere close by. Yet up at beach five there were plenty.
 
Is this a case of NIMBY over-reaction or is jet skying one of those recreations that really does needs to be controlled in national parks?

Kings Tides and beach profile

At the same time as last weeks, transit of venus there was also a full moon and a very low atmospheric depression out to the east over the Tasman Sea.. Perfect conditions for a really high tide. I did check the beach on the 7th. and could only see the old erosion face from last year and the regrowth on the sand screen below them. There was a slight notch in several location that looked as if it could be more than a few days old but it was not very extensive (these are labeled in white in the above photo). I revisited the same areas south of beach one today and can see a fresh cut (only 5 to 20cm tall) but extending most of the way along the beach (labeled in yellow). Also the beach below the cut does seem to be “steeper”. So I suspect there has been some significant erosion/sand movement along the beach in the past week. So the picture that the erosion events are most likely to occur with the king tides (full moon) and atmospheric lows does have a little more circumstantial support.

Venus Bay Inspired Art

The Last Pipi Harvest at Venus Bay

Mixed Media on Canvas
102 by 102cm
By Norm Hanson 2012
This is a story of anthropogenic extinction, as written into future stone. The ochre coloured sandstone [1] was at one time a thriving beach, brimming with life and specifically a prolific population of Donax Deltiodes, also known as Pipis or Surf clams. However the Pipis were so yummy and they were harvested in such numbers that fewer and fewer shells reached maturity each year. Then suddenly in one season, the entire population failed to reproduce. Worse the rich food chain of the beautiful beach collapsed, with their demise, and the once thriving beach became a pale version of itself. Only a few brave worm burrows [2] could be found. Then all signs of life disappeared [3].

This story need not come true.


The work was created first as a mould of the main units in the sand south of Beach one. This included leaving some of the worm burrow/air holes undisturbed. broken Pipis and other shells where collected nearby and scattered in the mould. The mould was filled with expanding polyurethane foam and cover with the canvas, burried and left to harden for an hour or so. The foam on canvas mould was next painted with several coats of sand, gesso and latex to create an absorbent sandstone like finish. Finally this was “stained” and painted with various oxides. It represents a future geological rock face, perhaps a few million years into our future. This rock face runs close to the bedding planes with the oldest layers, the ochre sandstone on the lower left, closest to you. You are looking "up" in time.

This work will be on display at the Mount View Art Show, 14th - 17th June 2012