Sunday, March 11, 2012

A Spring Tide Ecrehous

Saturday's high tide was predicted to be 11.8 metres or 38.8 feet, with a low tide of 0.5 metres or 1.7 feet. This is quite a large tide even by Jersey's standards.  With light winds forecast it seemed to good an opportunity to miss, the Ecrehous was our favoured destination but with 11.3 metres of water moving and tidal streams in excess of 5 knots at times the navigation needed to be more accurate than normal.
So at just gone 06.00 we were packing the sea kayaks on the rapidly disappearing beach at La Rocque.  The aim was to leave an hour before HW, in fact we were ready a few minutes early, so 06.30 saw us heading away from the south east corner of Jersey.  
Selecting La Rocque as opposed to St Catherine's our normal departure point gave us considerably more leeway as we approached the reef.  As our track from yesterday shows we did return to St Catherine's, if we had arrived back at the south east corner of the island we would have ended up having to carry the kayaks well over a mile as it was low water.
It was interesting to observe the impact that the pressure had on the height of the tide.  Tidal predictions in the UK are based on average atmospheric air pressure, which is 1013 mb.  The actual air pressure whilst we were paddling was 1040 mb.  This probably explains why when we were at the Ecrehous the tide wasn't as quite as high as we expected.  Then on arrival back at St Catherine's the tide was as low as I can remember for a long time.  The sea level drops 1 cm for every mb that the pressure is above 1013 mb, so the height of the tide would have been 27 cm lower than predicted.  
 Approaching the Ecrehous, they are the slight bumps to the left of the bow.  The crossing was just over 9 nm and it took just under two hours.  The last 3 nm passed rapidly as we experienced the full flow of the tide.
Alex approaching Maitre Ile, the largest of the islands on the reef.  We rarely land on this island choosing instead to head straight to Marmotier.
 On an 11.8 metre tide there is not much to see.  Marmotier is where the majority of the small houses are located.  This photograph was taken an hour after HW.
Looking north towards Blanche Ile.  The tide is flowing strongly north at this point.  A couple of hours later it was a simple walk along the shingle bank to the other houses.
When we arrived there was only one other person on the reef, with a few hours there were plenty of other visitors from both Jersey and France.
 Alex and John having a very early lunch or a late breakfast.  It was delightfully warm when sheltered from the NW breeze.
 The obligatory picture looking north from the bench.
 A 12.00 departure enabled us to gain maximum advantage from the low water slack in the main channel between Jersey and the Ecrehous.  We did head south along the reef though to ensure that we were at the optimum point for departure.
 Jersey ahead.  This view shows part of both the north and east coasts.  Using a hand held VHF we often find that there is a blind spot in close so we have to radio in when we are still about 0.5 nm offshore.
 Arriving at St Catherine's and it is still not low water.  It was not that easy getting the kayaks up the steps though.

A great day out and due to the alternative departure point what could have been a really challenging paddle became something which was relatively straight forward.

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