Dredging campaign could start as early as 21 Jan
Van Oord, who were awarded the contract to undertake maintenance dredging of parts of Salcombe estuary following a competitive tendering process, have confirmed that they could start the dredging campaign as soon as 21st January when their newest dredging vessel BORR completes its current tasking elsewhere. This date is of course weather dependent and may slip a few days if poor weather is encountered between now and then.
The type of dredging to be undertaken is known as Water Injection Dredging; water is used to lift the sediment from the estuary floor so that the tides and other natural forces can disperse it over a wider area. Comprehensive computer modelling – the accuracy of which was proven during the last dredge which took place in 2011 – estimates that at worst case, the estuary floor in non-dredged areas will rise by less than 3-10 cm. This means that navigation in the non-dredged areas won’t be adversely affected, whereas safety of navigation in the main (dredged) areas will be significantly improved.
The areas to be dredged include the Kingsbridge basin, an area around Lincombe Boatyard and several areas in and around Salcombe. These include the slipway and pontoons in Batson Creek, the Fish Quay and the channel from there to Salcombe and the Normandy, Whitestrand and RNLI lifeboat pontoons. Over 10,000 cubic metres of silt – equivalent to approximately 4 Olympic sized swimming pools – will be dredged over a number of outgoing tides. The scheduled length of the campaign is between 1-2 weeks in total, weather permitting.
The silting of the estuary is itself a natural phenomenon caused by run-off from surrounding countryside, and the harbour is regularly surveyed to judge where and when dredging is necessary; at the moment this is about every 5 years.
Impact on harbour users and the environment
The dredging campaign has been carefully planned and timed to cause minimum disruption to both harbour users and the environment. The biggest impact will be the need to temporarily move both vessels and pontoons off their pilings in the Kingsbridge Basin. This may limit individuals’ access to their boats during the 2-3 days that dredging occurs in Kingsbridge, but the Harbour Staff will make sure that everything is put back as it was.
Dredging vessel BORR
The BORR is a road-transportable dredger which is broken down for movement and re-assembled on site. It is approximately 19m long and 5m wide. Further details about the BORR can be found on the Van Oord website (note: SHA are not responsible for external content).