Stu, it's very, very easy to prove that any sand build ups prior to the commencement of the sand pumping were very transitory phenomena.

The QLD EPA which manages the TRESBP has aerial photos of Coolangatta/Kirra going back to Federation.

The current sand-build up at Kirra isn't going anywhere until some structural/engineering change is made to the sand bypass system.

Until then RIP Kirra.

Well what is more significant is the change they show. Sometimes the sand was stacked (though never to the same extent as it has been since the TRESBP) but other times it was cut right back.

There has been no such significant changes in beach profile since the start of the bypass so claims it is mimicking the natural sand flow are patently absurd.

Sand slugs came and went but the current set-up is much more permanent.

ergo there seems to be very little prospect for Kirra to return under the current sand pumping regime.

The problem with the Courier Mail article is just the classic one of seeing an obvious change around you and assuming that's the problem. It's a bit like the way old folk say that migrants are the reason Australia doesn't have the standard of living it had in the 1960s - well in the 1960s Australia actually made most of the stuff it consumed which it doesn't any more. For people in real estate to pin Kirra's problems on too much beach (rather than, for example, a world-wide correction in coastal apartment markets outside major cities is hilarious, seeing as the whole reason the sand pumping happened was the complete absence of beach from Kirra to Bilinga getting the property owners in a twist. "Where's our beach that we had in the 1960s?" They cried. And now they have it but it takes them longer to get across than they remember when they were kids. Obviously the beach is the problem.

I was lucky to surf Kirra through the 80s, and it was really something. But for a while there the superbank was also just as amazing, though different. Stu's point is right on, there's nothing natural about the whole setup, and telling the government not to mess with it is a bit misguided when it was only government meddling that made it in the first place. I'd prefer it if they pulled out all the rock walls (and the seawalls), stopped the pumping and let nature take its course but the chances of that happening are zero.

Look to NSI for some sort of natural comparison. Cylinder's banks and beaches come and go with the seasons, but as far as I can tell, there is still usually a 'positive sand budget' at the kilometre scale. E.g.: the high water mark is up near the carpark and eroding the vegetation, but you might be able to drive around Adder Rock on the sand at low tide.

Add to this the extra source of sand being swept north from the Tweed River, and it's hard to imagine that Rainbow Bay is naturally deep.

The difference between good banks for surfers, beach profiles and generally just sand in the bay has been talked about, but not actually systematically broken down and discussed. On the whole though I think both Stu and Freeride are not wrong. A sandy bay is more natural and a natural variation is the movement of sand slugs. Stu is taking a broader and easier to explain point of view; Freeride has too, then zoomed in to the scale at which really matters to us from week to week.

Then you've gotta question whether you can trust what people say anyway. Including the engineers.

Unfortunately observations made by all of us don't stack up to actual measurements, even with the aid of photos. Then consider the time passed and how people tend to remember and emphasise the good bits.

Even academics have suffered a little from an equivalent of the 'sound bite phenomenon' in the media. Some people might have heard that there's about half a million tonnes of sand moving north past the Goldy at any given point in time. It's a handy figure to know to give you some idea that there's a lot of sand moving north, but as far as I can tell (honestly I just stopped at finding one original source for this figure), it's based on the average of 1 month of data. Hardly, reliable. But 'cos it just gets used here and there in the intros to journal articles, conferences on coastal erosion, etc, most people probably wouldn't know what it actually represents, including me! What is a half a tonne of sand???

So the point is, do we even know what we're talking about? Are we all talking about the same thing? Does it even matter?

I think Stu has done well to give a simple explanation of what has happened. 1. Rock walls block some of the northward transport of sand, keeps the Tweed Bar navigable. 2. So they decided to take the blocked up sand and pump it in the general vicinity of where it would've ended up, if not for the walls.

Then to interpret from general observations and basic physics, it also makes sense. The timing of these changes roughly coincides with changes in the surf. More sand -> shallower bay -> less wave energy & fuller waves.

Cheers for reading if you stuck through to the end haha.

Sorry that figure is wrong, not tonnes at any one point in time. 500 000 cubic metres/ year.

And sorry Stu if I sound like I'm saying you're dumber than Freeride for not 'zooming in'. You kinda do talk about banks, etc; but it seems like you're focusing on a different scale and trying to keep it simple for everyone :-)

Artifical it may be but today i got a wave so long down coolangatta beach that my legs hurt!

mitchvq good perspective. Not many people refer to the amount of sand that was dumped in the middle of the bay. Now when the swell is big there are cloud breaks everywhere. In the 70's and 80's Kirra could hold a 8-10'swell with swells marching straight onto big groyne. No outside breaks.

It's the sand dumped in a grid in Coolangatta bay by the dredge that is a big part of the problem. That both absorbs alot of the swell energy by making it break and prevents some of the natural erosive forces from scouring some of the sand out of Kirra.

Sounds like there is now a strong possibility that Big Groyne will be re-extended back to '95 levels (when it was shortened at the behest of Peter Turner).

This would enlarge the dimensions of the "headland" and increase the erosive force on the northern side, hopefully improving the wave quality at Kirra by changing the angle of the sandbar.

Wouldn't extending the Big Groyne - coupled in with continual sand dumping at Snapper/Rainbow - straighten the Superbank section between about Grrenmount and Kirra, causing this part of the wave to close out more frequently?

Yeah, probably.

That part of the superbank would probably straighten but the Kirra section would (hopefully) come back.

Bruno Castaldi from the GCCM did some mathematical modelling on this and that was his (initial) conclusion.

So, everyone's willing to risk losing one of the better parts of the Superbank, just on the chance that Kirra is (hopefully) restored?

What if we lose the Greenmount-Kirra section, and Kirra doesn't come back either?

Well, that section of the beach, traditionally called Spot X, needs a big swell to work, and at the moment, whilst it has some good to great moments is mostly a close-out with some barrelling sections.

It couldn't be compared to Kirra in any way.

Also, it would likely see Greenmount improve.

The very strong local consensus is that extending Big Groyne using sausage bags (should have mentioned that) would be a very worthwhile experiment with a scientific basis for improving wave quality at Kirra.

What's the theory behind Greenmount improving under this scenario?

At the moment there is a continuous sand-bar from Snapper down to North Kirra.

If the Kirra headland dimensions were increased that bar could become discontinuous as it was quite frequently through '74-2000.

That would see the sand bank hug tighter to Greenmount point as it once did.

Of course this is contingent on the sand flow budget through Coolangatta Bay.

I can't actually see the logic in that Steve - how can we see both Spot X 'probably straighten', as well as the 'sand bank hug tighter to Greenmount point as it once did'? It's gotta be one or the other.

I'm certainly not a coastal engineer, but in my eyes, increasing the Kirra groyne will probably create a larger sand trap for the northward littoral drift. My gut feeling is that we probably won't get the 'old' Kirra back at all, and we'll probably compromise the Superbank section between Greenmount and Kirra at the same time.

IMO, the only way to make a fundamental change to the situation at Kirra would be to completely stop pumping the sand into Coolangatta. Of course, this would have major implications for the entire Superbank.

Well it could easily be one or the other.

The crucial fact is increasing the headland dimension will change the angle of the sandbar accreting on the northern side and likely erode a bit of the sandbar on the Greenmount side.

This is likely to at first square up the angle of that last Cooly section (Spot X) and if sand erodes enough (via a big storm event) re-align closer to Greenmount point as in many times in the past.

The sand pumping jetty has no reservoir of sand to pump, they can only now pump what comes up the coast.
So, depending on natural movements of sand and storm events it's quite likely that increasing the Groyne will change the alignment of the sandbar to be more favourable to Kirra, probably straighten, then see the discontinuity of the Greenmount/Spot X section, possibly with a re-alignment back to the original Greenmount headland version.

It's really instructive to go sit on the end of Big Groyne in a major swell event and witness the effect of the current sweeping past the groyne and the way that shapes and aligns the sandbar.

The other important thing is that using sausage bags, if there is an enormous deleterious effect on the Superbank and Kirra does not re-align they can be taken out.

And the Sand pumping regime has now been proven many, many times to be capable of reconstructing the Superbank after the bank has been destroyed by storm events.

That's a good point about the sausage bags. As for everything else, I suppose only time will tell.

True.

The basic premise: change the headland dimensions and for a given sand flow budget you change the angle of the accreting sandbar.

This is very easily modelled.

what sort of dollars are we talking for the sand bags? and wont they eventually breakdown as per the Indian reef & i assume what happened at Narrowneck.

So far, the government has allocated $1.5 million ..."towards the restoration of Kirra Beach", of which over $1 million has already been spent as a part of stages 1 and 2.

http://www.derm.qld.gov.au/environmental_management/coast_and_oceans/coa...

According to the Surfrider Foundation and the 'Bring Back Kirra' campaign, this has had "minimal impact on restoring the surf at Kirra Point, but has improved beach amenity."

http://www.kirrapoint.org/whatcanido.asp

In other words, $1 million was spent with absolutely no change to the surf at Kirra.

They're now suggesting to spend the remaining $500K as such:

.."extend the Big Groyne to its original dimensions (prior to removal) with basalt rocks to improve surf quality and restore Kirra Reef. Improvements to the groyne walkway and foreshore to be conducted by council after groyne restoration."

(note: this suggests the use of basalt rocks, and not sausage bags)

Personally, I can't see this magically restoring Kirra to its former glory either.

Also, Neil Lazarow's recommendations in 2007 included lengthening the Big Groyne by 30m.

Is this the same length they're talking about now, Steve?

I just measured 30m from the end of the groyne on Google Earth and the extension won't even reach past the existing sandbar, so I really can't see how it'll improve the situation.

and The Narrowneck artificial reef is that still there?..sorry for my ignorance

Yeah, and to be fair to Neil Lazarow he wasn't a huge supporter of lengthening the groyne by 30 m (he felt that was inadequate for the sand flow budget).

But putting back the 30 m that was taken off in 95 will change the water flow (longshore drift) out to a greater distance than 30 metres.

BTW stages one and two were some of the worst and most ill-thought out strategies the Govt could have conceived.

This is also pertinent.

http://www.tweedsandbypass.nsw.gov.au/feasibility_studies

It's also interesting to see from the UNSW camera image that the beach profile has eroded back a bit at Kirra and that extending the Groyne would likely help change the sandbar angle to a more beneficial one.

Take a look at the shot.

http://ci.wrl.unsw.edu.au/public/tweed/index.php?page=../../argus/kirra/...

Hang on, before we get into future engineering suggestions, I'm curious on where the recommendations from Stage 1 and 2 originated from.

A lot of money was spent with no positive outcome whatsoever, however I don't recall any major objections to the project at the time - everyone seemed to think it was going to do the trick.

Hence my developing sense of déjà vu.

Thats not correct Ben, there was no expectation that moving some sand off the beach would fix Kirra.

The Govt acted unilaterally before an election in an effort to be seen to be doing something.

This Document outlines the current options under consideration.

Look carefully at the Letitia Spit back-pumping option and see if you get deja-vu.

http://www.tweedsandbypass.nsw.gov.au/__data/assets/pdf_file/0006/162159...

Hang on - are you saying the government allocated $1.5 million to the restoration of Kirra without addressing any of the recommendations made by GCCM to GCCC?

If so, who made the recommendation to move sand from the beach?

BTW - there was plenty of favourable media coverage on the web around late 2009, discussing how the sand excavations were going to improve the surf quality at Kirra.

There's no mention in any of the Govt lit. about the GCCM recommendations which came from the surf community.

http://www.derm.qld.gov.au/environmental_management/coast_and_oceans/coa...

But according to the KirraPoint.org website:

'In 2010/11 KPI has been busy working with DERM and GCCC on the Second Stage of the Kirra Beach Restoration Project.

http://www.kirrapoint.org/media.asp

And from one of the media releases dated Dec 24 2010"

'Climate Change and Sustainability Minister Kate Jones said the efforts to restore Kirra to its former glory were working well.

"The evidence is in. The works to bring back Kirra’s famous break have made a real impact."'

Sure it's just government PR spin, but KPI were working with DERM at this time (another quote from the same press release: 'Kirra Point Inc Chairman Wayne Dean said the result of the works had exceeded expectations').

Look to be honest that is about the time I stopped working on it with Neil.

Up to that time I had regular contact with Wayne Deane.

His view was that the North Kirra outlet needed to go in and the the dredge needed to stop dumping sand in the bay.

Sounds like Wayne should be contacted directly for his views.

This seems pretty clear about what KPI stands for.

Which is line with the GCCM study and doesn't mention the beach scraping.

Long Term Solutions for Kirra Point - KPI Proposals

To restore Kirra Point as an amenity and surf break for the long term and allow Kirra Point as a surf break alongside the with the Superbank, ultimately an addition to the Superbank. Pumping would be maintained at East Snapper for the Superbank.
Return the 30 metres of rock to the Big Groyne Kirra Point removed in 1996 - requires GCCC and State Government (DERM) approvals.
This will:
Clean up the end of the big groyne Kirra as the submerged foundation rocks are hazardous/dangerous. The submerged rocks in their current state alter the sand flow around the big groyne and does not promote a good surfing bank.
Aid in coastal protection.
Return Kirra Point as an amenity and a surf break for the all of the public to enjoy.
The foundation rocks (some submerged, some not) of Kirra Big Groyne that were left by the council when the 30 metres was attempted to be removed winter 1996 change the water flow and this in turn does not promote a good surfing bank and encourages sand accretion at Kirra Beach. No community consultation was done prior to this removal of the 30 metres of Big Groyne.

Extend dredge deposition zones to allow sand placement at Bilinga and/or East Snapper Rocks, placement will depend on assessing where it’s required at that point in time - requires TRESBP and GCCC approvals.
Bilinga – when there is excessive sand in the East Snapper /Coolangatta bay area and the sand is not required at East Snapper Rocks. This solution was suggested in 2004 to TRESBP in community meetings when the volumes pumped were up to 2 times the natural littoral drift and Coolangatta was clogged up with sand. No sand should be placed in Coolangatta Bay.
Snapper Rocks East –when it is required and when there is a lack of sand at East Snapper Rocks. This situation can be will need to be closely managed and monitored in line with what nature throws upon us. Eg, the dredge could be utilized when there is a hole at Snapper Rocks and/or for preparation of surfing breaks for the Quicksilver Pro. Sand delivery should be in waters of a depth between 2-4 metres as this is the depth that allows for maximum sand movement and will link up with sand pumped from East Snapper Rocks onto the Superbank. Sand should not be placed in any waters deeper than 4 metres.

So back to my previous question - who made the recommendation to move sand from the beach, which the government acted upon?

Seems to me to have been a massive waste of taxpayer's money so far.

They've only got $500K left and most of the GCCM recommendations are significantly more expensive than that.

Good question.

Neil or Wayne would be able to answer that one.

But I was there on the beach filming the trucks and diggers for Stage One and I remember saying to Neil, "holy fuck this is a waste of money" and he was inclined to agree with me.

I've just stumbled across some old communication from Dec 2009 which suggests KPI were actively working with DERM in the lead up to the sand excavation. In fact, the emails even state that the government "was incredibly reluctant to move any sand at all", and that KPI "endorsed their plan".

Sorry boys. I think the chance of getting Kirra breaking like it did in th 70's, 80's and early 90's are dead and buried under shitloads of sand with grass growing on it and fences to keep us off it.
Maybe a new type of Kirra might happen with some coastal engineering and maybe it will be special in its own right.
Its going to cost a shit load of money to do it!
Start passing the hat around.

The success of all these measures including bagging and extension of the groyne are all limited by one thing - sand flow.

Remember - the aim of the whole system is to 1) improve navigation safety of the Tweed bar; 2) replenish southern beaches; 3) maintain a natural sand flow rate from the southern side of the Tweed River breakwalls to the southern goldy baches (i.e pre 60's levels)

Early operation years of the TRESB 2001 - 2006 were aimed at pumping above average (~500k cu.m/yr) of sand to replenish the southern gold coast beaches and clear the tweed river entrance. Natural variability can be between 200k - 1.2m cu.m/yr.

From the reports ive read including the publically available ones and some not publicaly available, the success off all these proposed measures has more to do with how far the dial is turned on the pumps rather than what rocks are placed where.

Rest assured that even if the TRESB operators say 'we promise to pump XXXX cu.m of sand a year', and a big cyclone occurs ripping shit out of the southern beaches - the dial will be turned back firmly to the right, meaning your carefully designed groyne extention will have the opposite of the desired affect.

It cant be peaches and cream all the time.....

Your're right P-funk it all comes down to sand flow but a few things need to be understood.

McConnel-Dowell are the company who run the TRESBP.

They constructed it under as a BOOT set-up. Build-own-operate-transfer.

That means they built, own and operate the sand bypass system.

They get paid per Cu. metre of sand pumped. When they began the project there was a huge sand reservoir off the south tweed walls/Letitia spit.
They pumped because sand was available and because they got paid per cu metre.

That sand is no longer available.

They can only pump what comes up the coast as part of the natural longshore sand flow.

So it's incorrect to assume they can turn the dials to 11 if a major storm hits the Goldy, especially one from the NE. They can only pump what sand is available.

There was only 395 609 cubic m pumped last year and 478 356 so far this year....which is around or just under the estimated 500 000 cu metres expected as the average.

So, it's reasonable to assume that increasing the Groyne dimensions won't be "buried" in excess sand the way it was when the sand bypass was first installed.

They simply don't have the sand reservoirs to pump like that anymore.