Topic: Sand - Twin Creeks
Twin Creeks is located immediately south of Beach Two. Its northern bluff is impassable.
As the name suggests, Twin Creeks consists of two creeks. One empties into a horseshoe type small bay or cove from the northern boundary, while the second creek empties into the bay from the southern boundary. This bay occupies the middle part of Twin Creeks. The seaward side of this bay extends both north and south for a short distance and is bounded by high cliffs. The northern cliff slopes down towards the beach and culminates in a standalone rock stack that I have called the Middle Rock. This resides in the middle of the bay between the northern and southern cliffs. The northern cliff ends in an arch.
This bay is accessible from the land which is low lying in the immediate vicinity. A farm road, part of the Whitecliffs Walkway, is situated on a low rise above the beach. This is however being reclaimed by the sea. As such it is in a highly active erosional state. Behind the road the land quickly rises into high, undulating hills.
While the bay is accessible, it doesn’t have an upper dry high tide zone in the usual sense. However, where the northern creek exits onto the beach, there is a narrow low lying shelf of land. The topography thus allows for the accumulation of logs and as such, this is a permanent log debris field location. Individually, the local log residents may change over time, but I have never observed a time when there haven’t been any logs at all. Sometimes, during periods of high sand cover and low high tides, sand and/or round stones can build up sufficiently to form a temporary dry upper high tidal zone in association with the log debris field
Logs also accumulate where the southern creek exits onto the beach, but the debris field is much smaller and more transitory. Also, as with the northern creek, during high sand cover, particularly when pushed upwards at the landward ends of the beach, a temporary dry upper high tide zone can exist in association with the southern creek’s debris field.
The short beach located on the seaward side of the bay has no dry high tide area. This is because high cliffs rise sharply from the beach. These cliffs culminate in an impassable bluff that forms the northern boundary with Beach Two and another impassable bluff that forms the southern boundary that leads around to Whitecliffs.
Because this area as a whole juts further out to seaward than Beach Two, the beach width between the low tide mark and the cliffs tends to be narrrow. This is because at low tide, the tide does not go out as far. This can be misleading though, because if one chooses to measure how far out the tide goes from the landward side of the bay (where the creeks exit onto the beach), then the incoming/outgoing tide covers a greater distance than when measured from the cliffs that are closer to seaward.
Overall, the sand cover is usually good. However, in the horseshoe bay area of Twin Creeks, it can sometimes be heavily scoured out down to bedrock. In the vicinity of where the twin creeks empty onto the beach, sand shelves can form on either side of the water as it travels across the beach and into the sea. This shelving tends to be more prominent on the landward sides of the streams. The shelving is in a constant state of change because the creeks that create them are in a constant state of change. The northern creek passes through an arch that is located at the base of the northern cliff that slumps down onto the beach.
Sometimes, a short distance seaward of the Middle Rock, the beach can slump quite dramatically downwards towards and into the sea. The unique topography of the Twin Creeks area creates a more volatile sea state. There are a lot of backwash and dumper waves. Dumper waves are either created by the slumping beach or they are a particular variety of wave that causes the beach to slump, I don’t know.
Due to the short distance between the sea and the cliffs, waves don’t have far to travel to reach the cliffs. This translates into access being restricted. When I have been able to access the beach either north or south of the Middle Rock, the sand cover has always been good. One thing to note is that I have never ever seen any cliff fall debris here. The only exception being the forming arch collapse debris at the entrance to the cave. This is located immediately south of the Middle Rock. This doesn’t mean that cliff falls don’t occur, just that due to the particularly dynamic sea state that prevails here, no debris survives long enough for me to have observed it.
An unusual feature of the beach, specifically the bay area which is essentially in the middle of Twin Creeks (as a whole), are some fossil tree trunk and stump remains. These are covered/uncovered to varying degrees dependent upon beach height level.
This was my rist visit to Twin Creeks. I didn’t mention the beach state. As the tide was high I couldn’t anyway, had I thought of it. The photo was taken from the southern cliff-top, (the Top Paddock) and gives an overview of Twin Creeks as a whole. The horseshoe bay located in the middle is partially obscured. I have only mentioned this visit because it was my first one. The weather was fine and fairly breezy. A moderate sea was running.
9.12.2003 PHO2008-469- 472, 1154
A 0.8m low tide was due at 5.14 pm. The day was wrapped up in a blanket of low cloud. There was a very slight to nothing north-east breeze and the sea state was virtually flat. Though it had been wet with more wet to come, the road was driveable with care. On arrival at Twin Creeks, the first thing I noticed was that there were a number of dark tree trunks. It was as if an artist had plonked them in the sand to provide stark relief from the effeminate round rocks that lazed near the streams. A pool enclosed one of the logs. I later discovered that these were the fossilized remains of a coastal forest that had inhabited the area when the sea level was lower than today. I don’t mention the beach height, but as the logs were clearly visible, then the sand level wasn’t very high.
To access the beach beyond the Middle Rock, I strolled past the jutting tree trunks. They were only about a metre high. I then went around to the left (south), side of the Middle Rock as the tide was low enough to get on the seaward side of it. First, I had to splash through the left-sided stream. What a sight! The gargantuan cliff, swooshing around to a jutting headland, afforded a peak of White Cliff’s snout. A huge cavern was in the process of being carved out. There were a couple of other tidily caves, then two surfcasters. When I peered at them through my camera lens, they appeared to be lost in the vastness of cliffs and blackness of the well endowed beach.
On the right (northern) side of the Middle Rock, the sand level was also good, but in the vicinity of the arch, sand islands and water channels were present. This was caused by water flowing through it from the northern creek.
8.2.2004 PHO2008-655-656, 659, 662, 665, 669-670,
CLIFF SEQUENCING. A 0.4m low tide was due at 6.32 pm. It was wet and thundery at first, but brightened up later. The sea was choppy and there was a stiff onshore westerly. It had been wet for some time. The twin creeks were in flood mode but weren’t raging torrents. The usual logjam was present where the northern creek exited onto the beach.
The beach had good sand cover. On the northern side of the bay, a milky brown stream oozed across part of the beach. This was from a collapsed bank that was slowly melting under the onslaught of water. Rocks were present on the landward side of where the southern creek entered the beach. The sand cover on the seaward side of the cliffs, like that of the bay, was also good. I observed that the sea was so warm that it felt like tepid bathwater.
29.2.2004 PHO2008-686, 688-691
SUPER-STORM EVENT. Super-Storm Three. This was the third in a trilogy of potent storms that slammed into the country this month. A low high tide of 2.5 metres was due at 5.19 pm. The high low tide was 1.4 metres. I wanted to go down to Twin Creeks to document the devastation. Such was the volume of water that fell out of the sky, the road had virtually melted under the liquid onslaught. Driving was impossible, so I had to trudge all the way down to Twin Creeks. Though the sky was leaden, the worst of the weather had occurred yesterday, Saturday.
Upon arrival at Twin Creeks, a logjam of logs, mud and a cliff collapse welcomed me. As for the sea, it was wild, huge, frothy, a true tigress today. As for the two creeks, well, they were at their torrential best, or worst, depending on your viewpoint. And the wind was such that it kept threatening to rip my woollen hat off. I climbed up onto a small knoll and took a series of images panning from left to right. From what I could see of the beach, lots or round stones were piled up at the northern end of the bay on the seaward side of the creek. Rocks and logs were also present elsewhere in the bay. The sand cover appeared to be reasonable.
6.11.2005 PHO2008-1480, 1483, 1485, 1489.
A 0.7m low tide was due at 7.47 pm. There was little wind and the sun made a weak appearance. At the bay, the beach level appeared quite low as a lot of ancient tree remnants were exposed. The beach state was probably a legacy of the alpha storm that had struck the coastline on 19.9.05. I also took a photo, (PHO2008-1489) from the Maori Pa Promontory that looked north along the beach. This overlook marks the northern boundary of Twin Creeks.
Stormy conditions have prevailed for a while. I wanted to photograph Twin Creeks under these conditions as it’s something I haven’t done before. A 3.6m high tide was due at 2.01 pm. At Twin Creeks I wasn’t disappointed. The surf was boiling. Lots of foam, round stones and logs were backed up at the point where the northern stream entered the beach. The sea easily overtops this low lying land shelf during big seas combined with big high tides.
27.10.2007 PHO2011-1072-1073, 1077, 1082
A 0.1m low tide was due at 5.22 pm. The weather was fine with a cool south-easterly.
Down at the beach there was the usual resident log pile where the northern creek entered the beach. The sand level was good. I couldn’t see any sign of one of the rock shelves, but it could have been covered in sand. (I haven’t mentioned rock shelves in my previous diary entries – I could be referring to bedrock located at the landward end of the bay). The Middle Rock had lost its middle section. This is detailed in Section Six on Sea Stacks. Just south of the Middle Rock, part of a fossilized tree stump was visible. It had mussel spat growing on it. I saw the tops of three of these ancient trees. As well as photographing on the beach, I took some location photos from the cliff-top looking north. A fractured rock ‘caterpillar’ was partially visible on the beach at the southern end of Twin Creeks. Rock caterpillar formations are generally aligned at an east/west angle to the beach, whereas rock shelves are usually aligned in a south/north direction with the beach.
9.3.2008 PHO2011-1180, 1188
A 0.2m low tide was due at 6.09 pm. The weather was cloudy with a brisk westerly. The beach level in the bay was exceptionally high, particularly to landward. It was like it had been piled up with a thousand bulldozers, while below the Middle Rock, the beach level fell away quite dramatically. Both creeks were running exceptionally low. This summer had left everything looking like the Australian Outback.
The usual flotilla of logs inhabited the area where the northern creek entered the beach. Logs lazed in the water and on the landward side of where the southern creek entered the beach in the bay area.
6.4.2008 PHO2011-1193, 1196
A 0.2m low tide was due at 4.00 pm. The weather was stinking hot, sunny and there was no wind. Sand cover remained at a high level. There was the usual log pile where the northern creek entered the beach. A scattering of logs also dotted the landward end of the beach leading around to the southern creek.
A 0.3m low tide was due at 3.14 pm. At Tonga the weather was fine with no wind. Down where the northern creek entered the beach, there was the usual log jam. Once on the beach, I noticed how incredibly built up it was and there was an even higher sand shelf that extended outwards from the slumping land. From this shelf there was around a one and a half foot drop to the beach proper. Both creeks were running low.
On the seaward side of the Middle Rock, the beach dropped away sharply.
12.10.2008 PHO2011-1342, 1344, 1347
A 0.8m low tide was due at 2.54 pm. The weather was hot and fine. Where the northern creek entered the beach, the usual log residents were present, but they were now accompanied by lots of medium sized rounded stones. They had been piled up against the logs and bank, tossed up like giant grains of sand by an impetuous sea. Part of the bank was also preferentially carved out by pummelling waves. The beach was well endowed with sand. Beyond the Middle Rock, the beach remained levelled out. It didn’t drop away as it has done fairly recently.
15.12.2008 PHO2011-1477, 1479
A 0.3m low tide was due at 6.56 pm. The weather was overcast with a slight drizzle. A slight breeze was blowing. I stopped the car just before the rise. This was because I wanted to take a shot with the 105 mm lens at the spot where the northern creek reached the beach. This spot was just above the high tide mark and it was usually jammed solid with logs. Today was no exception. On other occasions however, sometimes the logs were shifted further over. Also, oversized ‘pebbles’ (rounded stones) were periodically deposited here by the sea.
I have wondered whether these stones and even larger versions of them that are to be found on Beaches One and Two, are scaled up versions of sand grains. It would be interesting to see. It would also be interesting to know if the scaling is fractal in nature.
Aside from the stones, from what I could see of the beach, the sand level appeared to be good.
A 1.2m low tide was due at 11.25 am. The weather was fine with some high cloud. What breeze there was came from the north-east. The sea state was mostly glassy. As the road close to the Locked Gate above Beach One was in danger of slipping down the cliff, one couldn’t drive along it. The Gibbs’ have carved out a rough track to landward of this, but at this point in time, access wasn’t possible. Also, it is only passable in dry conditions. So, I had to traipse all the way down. As I wanted to try out my shiny new toy, Adam Buckle’s panoramic camera, I made the decision to only take that camera with me. As it is all manual, I calculated the correct exposures to be 1/60 at f11.5.
Down at Twin Creeks, I set up shop next to the resident log pile where the northern creek entered the beach. With this camera, I could get a panoramic view that would encompass the Twin Creeks inner bay area. The bluff in the background forms the southern boundary that leads around to White Cliffs. The beach had ‘shelved up’ to the bare sided bank on the left hand side. It then gentled sloped down to the beach proper where the sand cover was good. Afterwards, I took a photo from the cliff top paddock looking north along Twin Creeks. As the tide was quite high, the beach state was assumed to be good.
18.10.2009 PHO2011-1913, 1915-1916, 1919
A 0.3m low tide was due at 4.41 pm. There was a light to moderate southerly breeze. It was partly cloudy with some showers. I wanted to visit Twin Creeks as it had been several months since my last visit on 20.4.09. We have had a lot of grotsville weather of late and I didn’t think I would be able to drive down. I was right. Still, I was prepared. Bearing in mind that I would have to walk there and back from the Locked Gate, I resolved only to take my digital camera.
Down at Twin Creeks, both streams were running high and there was the usual logjam of logs, but they were more extensive than usual. The most obvious thing I noticed however was that the arch on the northern side had gone. Close to the northern stream where it exited onto the beach, the slumping land appeared to be preferentially eroding from north to south. (It being ‘eaten away’ by water from south to north). The beach state appeared to be good. I then went up to the cliff-top paddock and took some photos of Twin Creeks looking north. Again, the sand cover, what I could see, appeared to be good.
Today was a weather window between fronts. A 0.3m low tide was due at 4.18 pm. As I had come to document White Cliffs, I didn’t stop to do any photography at Twin Creeks. I did notice however that the beach level appeared to be very good, especially to landwards.