Beach One Christmas Day

Beach One Venus Bay

Christmas sunrise at Beach One, Venus Bay. As imageo mentioned in his last blog, the low air pressure and Lunar influence combined might lead to further sand movements and erosion along Venus Bay's coastline. The picture left has mounds of sand running parallel to the shore, and right shows how uneven the erosion to the berm is, as it persists in these deeper troughs. The fore-dune has experienced some erosion in places too.

Behind it the primary dune is suffering blow outs, often caused by people walking up and over the dune system, then enlarged by prevailing winds. We would remind people that besides being important habitat, the dune vegetation plays a critical role in stabilising the dunes, ie the beach. Besides that have a happy and safe Christmas, enjoy the beach and drive carefully.

Lunar Eclipse @ Sunset Tuesday 21st.!

For those interested, and clouds permitting, you will be able to a partial eclipse of the moon should be visible just before sunset as the "full" moon rises (approx 8:40pm) and best time to view will be as the sunsets, with the moon still low on the horizon and appearing larger than usual. The partial eclipse will reach it midpoint around 9:15PM and be complete by 10pm It should have a reddish colouration over much of the moons surface (not as complete as shown in photo from the June 2009 lunar eclipse but distinctly reddish all the same).

The best places to view the eclipse at Venus Bay will those places with a good view of the eastern horizon, such as the overflow Carpark on the way to beach one, OR on the Venus Bay/Lower Tarwin bike track at the beginning of Jupiter drive OR at the boat ramp at Estate 2.

Wikipedia has more details on this eclipse. This Blog has details of best viewing time for some Australian cities.

The 21st also marks the summer solstice (the shortest night of the years), The full moon and the tails of low air pressure and cold front (bringing the cold and cloudy weather) may bring higher than average tides and a slight possibility of more erosion and sand movement at the top of the beach. All in all a good night to get out and take a look at what is going on, albeit with a raincoast and umberella.

Beach One berm watch

This is the state of the berm at Beach One on 2nd December. View is towards Southeast during the low tide, at 11 AM.

Note the lower inter-tidal zone with sandbars and sitting water.

Beach Five update

Visited beach 5 today and took these photos of the fore-dune. To the West the dune looks alot more stable compared to the view East where the active undercutting is visible. The seaward half of the inter-tidal zone is fluffy with the transported sand. I also counted 6 dead Shearwaters. Also found my 1st Pipi from here with a Natacadea borehole. Usually these predatory snails are out competed by more efficient hunters.

What is a Spit?

The geomorhpic definition of Spit is a sandy bar projecting from the mainland into open water. Spits are formed by deposition of sediments moved by longshore drift. (here is a wikipedia link on spits, if you want more details)

So the Big question; Is Point Symthe a Spit?

Well it is widely described as a spit in tourist literature guide books, Often as Victroia's largest spit. However there may be a few problems calling it a true spit

1) The Andersen inlet estuary is no longer "open water" and there is a very strong tidal inflow and outflow cutting across the longshore drift

2) Observations in this project suggest that the longshore drift does change directions and has been larger going southwards for the past few years

3) It doesn't have the characteristic hooked end.

Yet physically it is a very large continuous section of sand and the present situation may represent a very late stage of spit development. Where by the entrance to Andersen inlet may close over with a continous sand bar from Point Symthe to Inverloch.

However as Andersen inlet gradually fills with sediment (not sure if anyone is accurately measuring this) The effects of the tidal flows (it is the same amount of tidal change but in a progressively shallower inlet) mean that there is now considerable erosion cause along the main chanels giving outlet to the sea. These infact are behaving like a meandering streams thrashing back and forth across the inlet floor and heavily eroding the coast & beaches but just at very specific locations (where the chanels curve most).

Who will win? Longshore drift or the tidal flow from Andersen Inlet.