In two areas of Rhu Marina berths were no longer usable because of severe build up of silt deposits over many years. Land & Water Services were employed by Quay Marinas, having worked successfully with them before, to remove the silts and restore access to a new pontoon system being installed.

The Land & Water ‘Wight Silt’ a highly manoeuvrable and versatile vessel was deployed to carry out the dredging operation.

Commencing on the last day of January 2011, working seven hours per day on the falling tide over a period of six days, 4,000 m3 of silts were removed. A minimum water depth of 1.5 meters at all states of the tide was achieved even in areas previously inaccessible and completely dried out.

Learn more about Land & Water’s dredging skills.

The existing channel at Ashley Avenue was taking urban run off from the local housing and trading estates along with the nearby South Downs, which was prone to flash flooding. The Environment Agency secured the services of Land & Water to upgrade a culverted section which ran through a residential area.

Access to these works was extremely difficult and severely restricted by narrow channel widths. The design was to create a two stage channel the first being a lower deep channel to accommodate mean flow rates the second or upper channel to be wider to take high water flows and increase the channels capacity in flood events.

Land & Water Services were approached by the Royal North Yacht Club to remove a build up of sands and silts from in and around the mooring bays of Blyth Marina.

There were particular problems under the two cranes used to lift vessels into and out of the water. Operating their bespoke SiltTek water erosion system. Land & Water removed over 4,000m3 of soft silts from the areas restoring easy access to berths.

The system work by blasting water via the pipe system at approx. 7 Bar pressure directly into the silts forcing them up and into suspension. By working only on the falling tide (one hour before to one hour after) these suspended solids are taken away naturally on the tide and widely dispersed. The method proved highly effective around the post and anchor chain moorings where conventional backhoe dredging cannot be deployed.

Project Information

Download Land & Water Case Study - Blyth Marina Water Erosion Dredging