Two types of dredging technique are employed: The ships are predominantly registered in the UK and have a replacement cost of between £25 and £50 million each.Īt the heart of the dredging process are powerful electric pumps which, on large vessels, are capable of drawing up to 2,600 tonnes of sand and gravel an hour from water depths of up to 60m. “That’s a 16-17m (52.5ft-56ft) lowering of the lough bed as a result of extraction.The nation’s marine aggregate needs are satisfied by a fleet of 27 purpose-built marine aggregate dredging vessels, operating around the clock, 360 days-a-year. “However, years of extraction has removed sediments from the bed such that depths are now, in places, 21m (69ft) deep. “The lough bed used to be around four to five metres (13ft - 16.4ft) deep in that part of the lough,” Dr Hackney told The Detail. His work found that sand dredging alone has created scars of up to 56 feet deep (17 metres) in places.ĭredging has also caused several deep ‘pock marks’ of up to 19.6ft (6m) deep. Research carried out by sand mining expert Dr Chris Hackney, which The Detail published in December, has shown that industrial sand extraction has left long-term scarring on the bed of the lough.ĭr Hackney surveyed an area where sand dredgers have been active in recent years. Workers initially used shovels to remove sand for use in building projects.īut over the decades, extraction has become a major business.Ĭompanies now use suction hoses and dredgers more than 60 metres in length to remove more than a million tonnes of sand from the bed of the lough every year.ĭespite concerns about the impact of dredging on the lough, no Stormont department or public authority regularly monitors the effect of extraction. SAND has been extracted from Lough Neagh for more than a century. Sand has been dredged from Lough Neagh for decades
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