A few quiet waves

Not far from a deserted Island

Work on Moana Rua Rd slip

Encroachment by heavy seas checked

ODT By Allison Rudd on Mon, 27 Jul 2009

It was estimates $50,000-$60,000 had been spent at Middle beach in the past few days trying to protect rock mattresses laid at the base of the dunes, which had been exposed by last week's heavy seas, and trucking in sand dredged from Otago Harbour and tipping it down the face of the dunes.He estimated the width of the dunes had decreased by 2m-3m in the past two years.The end of Moana Rua Rd fell away last Thursday, and the face of the dunes was now close to a large fence erected in 2007 to stop people from using a dune-top track which has also since succumbed to the sea.

It was difficult to believe the Moana Rua surf club building had once sat between the end of the road and the beach, he said.

"When we demolished that [in 2001] there was a lot of criticism. People said it would have made a good restaurant. But the area it was sitting on does not exist any more."

Surf Art from photographs

All artworks painted in acrylics on canvas by Nic Reeves
commissions for artworks from photographs currently being taken now.

Above, original photo by Al Ashworth.
Three below, original photos by David Pu'u.

Below, original pipeline photo by Ray Collins, (artwork now for sale)

'High Alert' as beach battered

full ODT article online here By David Loughrey on Sat, 25 Jul 2009
An ODT online poll was also run

Hotel nearing completion

Is Dunedin's beach erosion a sign of climate change?

From a POLL at the Otago Daily Times Sat, 25 Jul 2009
Below are two comments related to the POLL

Sand Erosion - Submitted by jade on Sat, 25/07/2009 - 9:05pm.

I have lived in Tomahawk for 35 years from 1960 to 1995 and lived right across the road from the sandhills. During that time I have seen the line of dunes going down to such an extend that I circulated a petition expressing concern at the excessive sandmining that occurred. (I believe it is still going strong). The Ocean Grove Domain Board members rubbed their hands in glee at the goldmine at their doorstep and took no notice of the petition that was signed by 95% of the residents. When we amalgamated with Dunedin I wrote to the Dunedin City Council expressing my concern at the continuing sandmining and the erosion of the dunes. I received an answer from a Mr Archer who wrote that the Dunedin City Council shared my concern and that something would be done as soon it came under the Council's jurisdiction. In 1995 I left Tomahawk, disappointed with the lack of action as the Dunedin City Council despite their promises, did absolutely nothing. I believe that the erosion at Tomahawk beach is not only caused by nature, it also did have a mighty helping hand by the continuing sandmining over so many years

Beach Erosion - Submitted by MikeStk on Mon, 27/07/2009 - 11:19am.
It really doesn't matter whether it's caused by global warming or not - the fact is that peak high tides are eating away the only protection South Dunedin has between it and the Pacific. And all the we really have there is a pile of sand.

It's not like peak high tides like this are not predictable (hint: all the fuss about solar eclipses is a little related, tide tables are readily available). Let's face it if the sand loss continues for much longer we're going to have to build something like a concrete dike from St Clair to Lawyers Head.

As I've mentioned in this forum before I think this is potentially the most pressing problem the council has before it - it's quite scary to read that they've not budgeted anything for the issue - instead we're blowing our piggy bank on vanity projects like the stadium - any sensible local body should have reserves for just this sort of occurrence or should have anticipated the problem and have planned ahead.

Ocean Beach Erosion Update

Above: today looking down towards St Clair, below, compare to a series of images over the last 2 years from a similar spot. Although the beach profile is lowered, there does not seem to be such an effect on the St Clair end, with most of the erosion around Moana Rua Road. Also a bit further along where the Tahuna outfall pipe was, has been gouged out more than the rest of the beach .

Above left: pulled back view , right: closer view of the digger work at Moana Rua, where in the last two days they have delivered truckloads of sand over the edge of the road, and replenished sand over the rock mattresses and boulders recently exposed at the base, as seen below:

Two days ago

Above photo taken on Wednesday from the base of Moana Rua Road at Middle Beach, note the scattered boulders on the sand at the base. Also the exposed rock mattresses. Significant lowering of beach profile.
Below left: the digger arrives, and first thing it tasks to is to dig up the scattered boulders on the sand(as seen in pic above)and place them on top of the rock mattresses. They are now all gone. Now, I understand that removing these actually cause more erosion. I was told that this was done at St Clair when they were building the new sea wall. Rocks were removed from the shoreline which caused significant lowering of the beach profile. They are actually needed to retain sand. Any thoughts on this?

Above right: damaged and exposed rock mattresses.
Article "Tides flood roads, erode dunes" at ODT.
Below, today St Clair, a good fill of sand at the base of the sea wall.
Motel progressing well, I think its looking pretty good!

Super high tides

Super High Tide at Brighton below, with a green wave breaking through the channel between Barneys and the beach. below again, a set at high tide surges up the beach.

Above double-time pic at Brighton looking down the creek to the beach, bottom image is a super high tide last year, same day the whale was beached at Ocean View. And above, a few days ago
Below: left Back Beach around from Brighton in May 2008, nice wide sand beach. Right, a few days ago photo taken from a bit further down the beach.

Above biting in to the dunes again last year.
Below: taken from back beach looking towards Taieri Mouth a few days ago.

Blackhead 1991 Covenant

Picked up a copy of the 1991 covenant placed on Blackhead headland yesterday from the department of Conservation.
Will read through today, and see what I can make of it, but from the skim, I can safely say I need to change drawing 'D'.

Pic Above: from the internet somewhere, showing a wide sand beach at Blackhead. Not sure what date perhaps about 3+ years ago?
Pic Below: late yesterday, again at high tide. Tide spilling over the top rock plateau.

I also took a walk along St Clair and St Kilda beach yesterday morning, and took some pics with the matchbox Pentax of the exaccerbated erosion, digger out playing with rock placement, exposed rock baskets and fresh dune erosion and slips.
Also a trip to Brighton later in the arvo, where the is a massive amount of erosion occuring at Back Beach. Pics coming of both those sessions.
Good news for me is last week I bought a second hand Canon 30D to replace my dying one, and hopefully it will arrive today in the post. Its been difficult for the last month not being able to take surf shots!

Blackhead Sand Levels

Yesterday at pretty much high tide.
Below, erosion occuring at Blackhead the same time the beach was washed out at St Clair and St Kilda with that series of south east storms/ beach emergency.



Above: a few weeks later, and then Right & Below: three months later.

Below: December same year, 2007

Below: April 2009.

Looking into Blackhead Quarrying

Following Information from here
Quarrying started at Blackhead in the 1950's and is now producing around 120,000 tonnes per year. Products range from general AP materials to high quality M4 roadbases, concrete aggregate, blasting sand, sealing chips and railway ballast.
Geology
Blackhead is a promontory of black basalt situated on the coast approximately 5km south east of Dunedin City's St Clair Beach. Composed of volcanic basalt it was formed about 10 million years ago during the third eruptive phase of the Dunedin volcanic complex. Columnar jointing on the basalt was formed during this cooling and this produced regular sided columns helping the crushing process.
Quality
The high quality resource is used to produce top end products i.e. M4 roadbase, concrete aggregates and sealing chips. To assure anything produced at the Blackhead Quarry meets specification there is an on site laboratory. The entire operation is externally audited for quality assurance to ISO 9001-2000.
Environment
Blackhead Quarry has a covenant; put in place in 1990, to protect unique rock formations at sea level. Blackhead has 0.7 hectares of settling ponds for water treatment. Dust is controlled throughout the plant by the use of water sprays and dust deposited at the boundary is monitored monthly.The quarry was the winner of the 1995 Nissan Diesel Environmental Award and the 1996 winner of the Winstone Safety Award.
Quarrying
Rock is won by drill and blast with a pattern of 2.7m x 3.3m x 10m bench heights. A 30 tonne excavator is used to load a 10 cubic metre rock truck to transport rock to the primary crusher. A 20 tonne loader is also used on the face for general tidyup, road maintenance and load out duties.
Quarried rock is tipped into a 70 tonne hopper and fed to a Nordberg 40 x 30 single toggle jaw crusher which feeds to a 6000 tonne surge pile. An Allis H4000 cone crusher then crushes the rock to 65mm with a screen taking out roadbases, the oversize then feeds a No. I Kumbee for railway ballast production. Any overrun goes to a surgepile to feed a Barmac 9600 duopactor used to produce sealing chips, concrete aggregates and sand. The plant is highly mechanised with video monitoring from the weighbridge. A 20 tonne front end loader handles sales from the stock pile with everything sold over a 13m computerised weighbridge.

	Stone is the most widely used construction material in the world. NZ communities need quarried products to build and maintain homes, hospital, schools and roads
	An average NZ house requires about 250 tonnes of aggregate during construction
	Aggregate makes up part or all of the materials for...
	Concrete tile roofing Brick cladding Gib board & wall linings Concrete for driveways & retaining walls Pavers & paving slabs The base course & top course Concrete floor slab base fill
	1km of highway requires 4000 tonnes of aggregate during construction
	An average family of 4 creates a demand for 32 tonne of quarried material every year.

I'm over dollar reserves!!

Sold for $10.50 on trademe tonight.

arrrggghhhh!

Blackhead Quarry

Slightly different angle last year below