Branch
Report:
11th October 2006
Marine
Aggregate Dredging – The Future
On the 11th
October, members and guests attended a presentation by Dr Andrew Bellamy
from UMA titled ‘Marine Aggregate Dredging – The Future’. The
presentation focused on the supply of marine aggregate for the future.
Dr Bellamy provided a brief
explanation of the formation of both marine and terrestrial sand and
gravel deposits and the location of such licensed deposits in the UK. The
licences for the extraction of the marine sand and gravel are issued by
the Crown estate and there are currently licensed areas being worked in
the North sea, English channel, Bristol Channel and the Irish sea.
In England marine dredge
aggregate accounts for 7 – 8 % of total aggregates used and the government
states that the figure should not go below this. While in Wales the
National Assembly encourage it but they prefer it to be undertaken in
deeper water, although that has it’s own implications as the current
vessels do not have the equipment to reach down to such levels and the
decision has to be taken on whether to invest in new equipment.
Various examples of dredging
around the UK were discussed particularly the Bristol channel where the
National Assembly are wanting to reduce the volumes being dredged off the
Nash banks and it is thought that dredging will be stopped by 2010 off
those banks.
The perception that close in
dredging causes coastal erosion was also discussed and the reverse is
actually true. Marine dredged aggregate is widely used for the formation
of coastal defences and the restoration of beaches. The material is
dredged out at sea and then pumped onto the beaches by floating pipes.
Due to the climate change and the sea level rise it is though that there
will be an increase in the demand for this use of marine aggregate.
The planning aspect of marine
dredging was the final topic presented particularly the renewal of current
licences as if they are not renewed they will disappear and with a number
of licences due to expire in 2013 a lot off work needs to be put in ensure
that they are renewed as it can take between 10 -15 years to get a
licence.
Dr Bellamy concluded that
marine aggregate sources will continue to be needed and that there is a
huge volume of aggregate quality deposits in viable locations it is just
whether we will be allowed to continue extracting from them. The
presentation was followed by lively discussion and thoughtful debate.
