BELGIAN DREDGING contractor Baggerwerken Decloedt has carried out its fourth contract in a series of beach replenishment projects along Belgium's North Sea coast for the Flemish Ministry of Public Works.
The first three contracts, completed over the past seven years, covered a 9km stretch of coastline between Ostend and Wenduine. The current contract, carried out with sister company Dredging International and Jan de Nul in a TV Noordzee & Kust joint venture, began in early October and delivered 490,000m3 of sand to a 1km length of beach at Blankenberge, 5km south west of Zeebrugge.
Decloedt's trailer suction hopper dredger Vlaanderen XX brought sand from the access channels to Antwerp and Zeebrugge harbours. The vessel carried 3,000m3 of sand per trip along the coast to the site but because the Belgian coast has a shallow gradient, sand had to be pumped ashore from a considerable distance. Pumping was restricted to three hours either side of high tide, when the ship could get close enough to the coast.
Sand was carried by a 150m long floating pipeline connected to a 1.2km long submerged line and through a reclamation line which was up to 2.5km long. The sand had very little mud content and few shells which meant that it did not require cleaning.
The joint venture will begin the next phase early this year at Knokke, about 5km to the north east of Zeebrugge. Work will involve reclaiming up to 1M.m3 of sand for up to 2.5km of beach over 12 weeks.