PAST PROJECTS

Bournemouth Beach Replenishment winter 2015/16

Part of a 17-year Beach Management Scheme to protect Bournemouth’s coastline

LEAD AUTHORITY

Bournemouth Borough Council

WORKING WITH

Van Oord UK Ltd

START DATE

14th March 2016

END DATE

24th April 2016

Project Overview

  • This project is part of the larger 17-year Beach Management Scheme 2015-2032
  • A volume of 355,500m³ of dredged material was distributed on the beach between Bournemouth Pier and Solent Beach (existing groyne No. B16 in the west to No. B36 in the east)
  • Average dredging/pumping cycle time: 5½ – 6 hours
  • Total No. of loads: 134
  • Project cost: £3.9m
  • Cost per cubic metre placed: £10.97
Bournemouth Beach Replenishment scheme (pdf)

Project Description

Three submerged pipeline locations provided the route for dredged material to be deposited on the beach. Dredged material was distributed across the beach by way of a shore pipeline and bulldozers and was retained behind a temporary sand bund at the point of deposition.

Van Oord UK Ltd was the appointed contractor to supply Bournemouth with beach material of a strictly specified Particle Size Distribution (PSD). The material was sourced from CEMEX’s Crown Estate Licenced Dredging Area 137 to the west of the Isle of Wight. The trailing suction hopper dredger Volox Olympia was used to dredge the material from the seabed. The suction (drag) head incorporated a 65mm screen to prevent the accidental loading of unexploded bombs or explosive remnants of war into the vessel’s hopper. The hopper capacity ranged from between 2,500 to 3,200m dependent on fuel volumes.

The Volox Olympia sailed between Area 137 and each location 1 to 3 by a pre-determined route as agreed between stakeholders. Liaison between the Council, Contractor, two appointed Fisheries Liaison Officers and the fishing community was crucial to ensure smooth passage for the dredge vessel to site.

The dredger discharged by attaching to a floating pipeline (approx. 150m long) that was located at the offshore end of the sinker pipeline. The floating pipeline was connected to the 650m long sinker (seabed) pipeline that pumped material to shore. A final section of 200m on-shore pipeline distributed the material directly along the beach.