Coastal erosion thread
Submitted by velocityjohnno on Sat, 06/15/2019 - 10:47


Great responsibility!


At a more localised level around Newcastle, a few of us have a theory that in addition to the sand dune stabilisation (e.g. Nobbys) and shore stabilisation along Merewether/Bar Beach stretch, the restricted stormwater outflow onto the beaches has also adversely impacted the sand banks and waves. For example back in the day there were pretty consistent left and rights directly off the drain outflows at Merewether, South Bar, Southey, and Newcastle. Just a theory, but appears to be more than coincidental. As a side note the the restricted freshwater outflow has also contributed to the lower level of oysters around the rocks these days (change in salinity for spawning).


One thing to be mindful of when comparing the beach condition you see now with what you knew it to be decades ago....what you're seeing now could very well be the "natural" (i.e. closer to the long term/steady beach state) and what you recall as being all-time in your younger years may have been in a post-storm/early recovery phase.
As for groyne suddenly turning on ya...same rule applies, it can take 30 years for the consequences of a specific change to fully play out.
The reasons for these vary greatly.
nah....yeah...but, nah


VJ, any thoughts on use of tank traps as a coastal erosion measure plus anti-SUP device ;-) as opposed to the relatively harmless marram grass!
On a serious note does pretty sound dangerous and it is also interesting that they are being exposed as at some point that must have been the natural beach profile.
https://au.news.yahoo.com/potentially-fatal-hazard-exposed-on-popular-be...


Anyone use this?
nah....yeah...but, nah


From memory the 30s saw some whoppa tropical storms so that may explain denuded beach systems in the 40s. The ones up here on hte sunny coast really only achieved a "recovered state" from the high cyclonic activity of the 70s in the '00s.
nah....yeah...but, nah


VJ,
I was a bit disappointed by the Inq coverage TBH. Thought it would be more in depth, you'll get a better analysis in our forums and comments.
As for a control beach: Maybe for future forecast changes - i.e sea level rise - but all the erosion to date is human-induced so not sure there'd be any purpose of control data?
Also, each example is very individual. Humans have found myriad ways to screw to coastal zone.


Yeah, in terms of sea level rise, an untouched beach may be good. Though from what I understand, sea level rise will be erratic, not the same around Australia or the world, so perhaps it might come down to some places faring better than others irrespective of how original and intact it is.
Not sure, just spitballing.


Downunder Qldurr goes bananas at Troppo Climate Change report !
2011 Queensland Coastal Processes and Climate Change
Page 22 [ Qld Map ] > " Vulnerability to Varying Influence of Climate Change "
*SEQ - Minor Tidal Influence > (Minor = Drowning in a rising sea of 1-100 Floods)
*SEQ - Minor Cyclone Threat > (Minor = Sydney Cyclone Siren needs new batteries)
*Townsville - Minor Tidal Influence > (Minor = Noah: "Worst Flood ever on Earth!")
https://data.longpaddock.qld.gov.au/static/about/publications/pdf/qld-co...
Tbb advises to get a bigger Black texta & don't stop until all Of Qld is coloured in!


How are things looking around Sydney/Central Coast this week?
nah....yeah...but, nah


Perfect Timing mowgli..
Stockton Erosion turned out to be a living local history treasure trove.
Grom refashions the Erosion & Lockdown into a 300y/old Time Machine
https://www.youtube.com/watch?v=29SfNuvvxbs
Council have equally cool "Story Maps" for the erosion.
https://storymaps.arcgis.com/stories/75f46591f216484597cdcafc14fd8131


Thanks TBB.
The site is interesting....
nah....yeah...but, nah


NSW Central Coast (Recent erosion + Up dates)
4th June 2020 ECL - Old Bar
https://www.nbnnews.com.au/2020/06/04/council-looking-into-another-sand-...
Wamberal
June 2016 ECL
https://www.dailytelegraph.com.au/newslocal/central-coast/major-erosion-...
July 2017
https://www.nbnnews.com.au/2017/07/23/wamberal-residents-meet-over-erosion/
29th May 2020 ECL - NBN [ Video 2 mins ]
https://www.nbnnews.com.au/2020/05/29/wamberal-residents-call-for-sea-wa...
13 July 2020 Pre ECL - (Massive Snow-Hail Dump) Central Coast.
https://www.nbnnews.com.au/2020/07/13/wild-weather-white-christmas-in-ju...
14th July - Big Bombora Sets [ 11.6m ] (Cowabunga)
https://www.facebook.com/abccentralcoast/posts/3740393542642794
(current) re: shoredump's photo..(Now a Big News Story)
17th July 2020 ECL
https://thenewdaily.com.au/news/state/nsw/2020/07/17/central-coast-erosi...
CCN TV : Lead Report
https://coastcommunitynews.com.au/central-coast/news/2020/07/weekly-vide...
Wamberal (7)news [10 min Video]
https://www.facebook.com/7NEWSsydney/videos/764108207673453/
[0: 45]
https://www.facebook.com/7NewsAustralia/videos/evacuation-warning-after-...
Bigger tides tonight...
Bonus : 2020 ECL (Blooper)
Avoca: One of Craig's puny 'infragravity waves' hits pay dirt...(Oh! The Carnage!)
https://www.facebook.com/abccentralcoast/videos/611200963141073/


My local council in all their wisdom have started digging a giant ditch on the beach between the water line and sand dunes. They are then mixing the beach sand and cement with a hopper on the beach, laying the mix back on the beach, on a slope of 16 degrees apparently. Effectively turning part of the beach into concrete! They will then cover with sand (which will be washed off in winter) I am livid they have done this with no community consultation, or as far as I know, expert advice. Apparently, this is being done to protect the sand dunes from further erosion due to a road being in close proximity to the dunes. Stupid part is, with excavators and bobcats on the beach and all the digging, the dunes have collapsed and vegetation on the dunes has gone with it. One area is now a close to vertical drop 3.5m from the road. In my opinion, the road now has to be closed. I cant believe a beach is being turned into concrete to prevent coastal erosion. I can find no history or precedent of this happening anywhere. We are a small shire with no money, is the excuse for these works. (ie no funds for alternatives.) They have now spent $250 000.00 (federal government money to provide stimulus to local economy) to prevent potential erosion to dunes which they have now fucked with machinery anyway. I won`t name the shire but has anyone heard of this happening anywhere in Oz? I cant.
There's not really a coastal erosion thread that I can see, beyond some excellent articles on the site. Post up examples you find in your area, and maybe how the sand banks and wave quality change.