Exposed Sections

EXPORT CABLE / ADVISORY ANCHOR EXCLUSION ZONE
ALL MARINERS SHOULD NOTE THAT THERE IS AN ADVISORY ANCHOR EXCLUSION ZONE THAT EXTENDS FOR 200 METERS EITHER SIDE OF THE EXPOSED SECTIONS OF THE EXPORT CABLE AND YOU ARE REQUESTED TO AVOID ANCHORING IN THIS AREA, THIS ALSO INCLUDES ANCHORS THAT ARE ATTACHED TO STATIC FISHING GEAR
……………………………………………………………….
The following positions define the export cable route:
51° 43′.79N., 001° 14′.30E.(sub station)
51° 45′.00N., 001° 13′.24E.
51° 45′.72N., 001° 13′.01E.
51° 45′.98N., 001° 13′.06E.
51° 48′.28N., 001° 12′.79E.
51° 48′.38N., 001° 12′.68E.(shore)

If you require any further information please do not hesitate to contact Duncan Potter, Assistant O&M Manager, Gunfleet Sands Offshore Windfarm on 155 Tower Street, Brightlingsea Essex, CO7 0AW.

Duncan Potter
Assistant O&M Manager
Gunfleet Sands Offshore Windfarm
DONG Energy Power (UK) Ltd
Office: 01206 307915
Mobile: +44 (0) 7891 966595

NOTICE TO MARINERS No.13/12 C6

Date : On or about 8th March, 2012.

1. Station : Walker Lighted Buoy.

Position : Latitude 51° 53’.791N., Longitude 001° 33’.903E.

Amendment : Existing buoy discontinued and a new buoy established in lieu.

Characteristics: Pillar: Yellow above Black above Yellow: Q(9)15 seconds.

West Cardinal Topmark.

2. Station : S.W. Shipwash Lighted Buoy.

Position : Latitude 51° 54’.750N., Longitude 001° 34’.213E.

Amendment : Existing buoy discontinued and a new buoy established in lieu.

Characteristics: Pillar: Yellow: Fl.Y. 2.5 seconds. Yellow ‘X’ Topmark.

Trinity House Notice to Mariners 46/2011 C15 dated 15th December, 2011, previously refers.

No further notice will be given.

By Order,
Captain R.H. Barker,
Director of Navigational Requirements.

Trinity House,
London EC3N 4DH
9th February, 2012

NOTICE TO MARINERS

No.7/12  C3

EAST COAST OF ENGLAND

THAMES ESTUARY

APPROACHES TO THE SWALE

Date   : On or about 10^th February, 2012.

To facilitate the laying of a subsea cable through the Swale Channel it will be necessary for the following amendments be carried out:-

1.Station : Whitstable Street Lighted Buoy.

Position : Latitude 51° 24′.000N. Longitude 001° 01′.540E.

Amendment : To be temporarily moved to Latitude 51° 23′.850N. Longitude 001° 01′.800E.

2.Station : Pollard Spit Lighted Buoy

Position : Latitude 51° 22′.983N. Longitude 000° 58′.568E.

Amendment : To be temporarily removed.

3. Station : Ham Gat Lighted Buoy.

Position : Latitude 51° 23′.083N., Longitude 000° 58′.318E.

Amendment : To be temporarily removed.

No further notice will be given.

By Order,

R. H. Barker
Director of Navigational Requirements.

Trinity House,

Tower Hill,
London EC3N 4DH.

31^st January, 2012.

No.47/11 C16

—————-

EAST COAST OF ENGLAND

————————————-

NORTH FORELAND LIGHTHOUSE (ALL Vol.A.0966)

Latitude 51° 22’.494N., Longitude 001° 26’.705E

————————————————————–

Date : On or about 12th January, 2012.

Amendment : Light to be exhibited night-time only.

Mariners are advised that the above date differs from Trinity House Notice to Mariners

38/11 C12 dated 10th October, 2011, previously issued.

No further notice will be given.

By Order,
Captain R.H. Barker
Director of Navigational Requirements

Trinity House

Tower Hill
London
EC3N 4DH
15th December, 2011

No.46/11 C15

—————-

EAST COAST OF ENGLAND

———————————— -

APPROACHES TO HARWICH

—————————————

Date : On or about 8th March, 2012.

1. Station : Walker Lighted Buoy.

Position : Latitude 51° 53’.791N., Longitude 001° 33’.903E.

Amendment : Existing buoy discontinued and a new buoy established in lieu.

Characteristics: Pillar: Yellow above Black above Yellow: Q(9)15 seconds.

West Cardinal Topmark.

2. Station : S.W. Shipwash Lighted Buoy.

Position : Latitude 51° 54’.750N., Longitude 001° 34’.213E.

Amendment : Existing buoy discontinued and a new buoy established in lieu.

Characteristics: Pillar: Yellow: Fl.Y. 2.5 seconds. Yellow ‘X’ Topmark.

By Order,
Captain R.H. Barker
Director of Navigational Requirements

Trinity House,
London EC3N 4DH
15th December, 2011

NOTICE TO MARINERS

No.45/11 B8

—————

EAST COAST OF ENGLAND

—————————————-

COQUET LIGHTHOUSE (ALL Vol.A2780)

Latitude 55º 20′.033N., Longitude 001º 32′.387W

———————————————————

Date : On or about 8th March, 2012.

Amendment : Light to be exhibited night-time only.

By Order,

Captain R.H. Barker,
Director of Navigational Requirements.

Trinity House,
London EC3N 4DH.

7th December, 2011

The image above helps you understand what is seen within a sidescan image. This is the actual anomaly we found.

In March 2011, Stephen Read and myself collected data within the Deben Entrance for the first time with the new sidescanner/sounder/plotter. As the priority was to gather survey data and was unfamiliar with sidescanning, I didn’t get the chance to explore what appeared on the face of it to be a rock in deep water within the channel.

The anomaly was or indeed is located at
51° 58.975′N 1° 23.412′E

Although we made detailed passes over the anomaly confirming it wasn’t a navigational hazard, I didn’t explore it much further. My initial assumption was that it was a rock that had slipped from the adjacent coastal defenses. Today, I found some amazingly simple but effective software which searches all collected sidescan data available within a computer directory within a given radius and produces sidecan images that fall within that radius.

Below you can see the results. These images were taken from various angles including running straight over the top of the anolmaly.

[Show as slideshow]

I’d love to hear what you think it is although my own thought is that it’s a hard clay strata exposed rather than a ‘rock’ but it could be a large treasure chest !

Thanks in part to generous donations by users of this site, I’ve been able to refine the survey rig for 2012. The system now consists of:

Survey rig 2011-2012 Showing rugged laptop running drdepth using a live ethernet connection from the Humminbird 898c and all powered by an extremely compact 12v 22Ah Lithium Ion Battery Pack from Tracer

Hardware

Panasonic Toughbook CF-29
Humminbird 898c SI Combo chartplotter, sounder and sidescanner
Tracer Power supply

Software

DrDepth seabed mapping and capture software
Surfer 10 Surface Mapping Software
Global Mapper

The current task is to see how in a real world situation DrDepth succeeds in capturing and manipulating data in such a way as to allow for effective conversion to artwork. Dr Depth can effectively create a seabed chart as data is collected on the water. A predicted tidal correction can be applied to create a fairly accurate chart on the fly.

This is amazing to see and is somewhat like mowing the lawn, making it obvious which areas you’ve missed. The main issue is that the  output isn’t suitable for artwork production so at the moment, DrDepth can only be considered (an exceptional) aid to surveying. This leaves the process of manipulating raw captured data via a spreadsheet which has the positive side effect of making errors easier to find.

One of the real-world tests I’ll be running is comparing the difference in real terms between a chart produced using predicted or real tidal data, perhaps with a flat offset to compensate for a difference on the day.

Correcting and filtering of raw survey data can easily take 7 or 8 hours, a lot of work to then establish you’ve missed something, so these practical tests are important.

I’ve only just discovered Global Mapper which is software that can visualize pretty much any geographical data and georeference images. My first efforts in georeferencing aerial photographs, effectively warping them to a chart, have been very encouraging. I’ve added a rather large kml file (for display in Google Earth) of the latest Deben Sketchmap for download here which is mapped to display in Google earth. It’s great to see features marrying up and also shows how much the bar has changed since Google last collected imagery.

No. 43/11 C14

——————

EAST COAST OF ENGLAND

————————————

THAMES ESTUARY

————————–

GORE AND COPPERAS CHANNELS

————————————————

Date    :  On or about 7^th February, 2012.

1.         Station            :           E. Last Lighted Buoy.

Amendment    :           To be moved 140 deg 916 metres to

Latitude 51° 23′.63N., Longitude 001° 12′.56E. and renamed “Reculver”.

2.         Station            :           Hook Spit Lighted Buoy.

Amendment    :           To be moved 244 deg 1175 metres to

Latitude 51° 23′.81N., Longitude 001° 11′.18E. and renamed “Copperas”.

Movements to be effected consequent upon progressive surveys showing migration of

the banks on both sides of the Gore Channel.

By Order,

Captain R. H. Barker

Director of Navigational Requirements.

Trinity House,

London EC3N 4DH

10^th November, 2011.