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| [06 May 08] :: FAIRWAY BEACON - WAVE AND CURRENT MONITORING STATIONS |
 A recent meeting of the Port Nelson Environment Committee took to the water and headed out for a close inspection of the new North Cardinal Beacon. Friends of Nelson Haven member Pam Frahm was on board to report. The Port found there was a need to provide more certainty to Pilots regarding under keel clearance during periods of swells. They needed to install real time wave and current measuring equipment, to assist in identifying waves that will increase a vessel’s draft through ship movement, and to schedule ship arrivals and departures using the actual current flowing. What the Port was seeking in real time was a warning system that informs pilots that because of the height and period of the waves, extra depth in the outer channel needs to be carefully assessed and for them to use the information to minimize the risk of vessels touching the bottom. Wave data will be collected continuously for the future. Real time current meters mean that in tidal ports shipping movements are timed according to the actual current flowing and not to a time linked to a tidal prediction. A single tubular steel beacon pile was driven 11.5 m into the seabed, 4km off the harbour entrance, close to the pilot station in 10 metres of water depth. It acts as a fairway marker beacon and also houses a considerable amount of instrumentation, positioned on a platform some 6 - 12 m above the high water mark. The instrumentation includes: · A navigation light of 9 nm · Triangular beacons (daytime marking) · Radar reflector · Wave height recorder/tide gauge · Wind speed recorder (Anemometer) · Batteries · Solar panels · Sender unit The wave height and interval is also of assistance in the dump ground study. This wave information would feed into a possible computer model to show how waves could be affecting sediment movement across the sea floor. |
| posted on 06 May 08 @ 11:54 Show all news |
