Posted on May 8, 2017
By Paul Speller, IOMToday
Rivers are being to assessed to see whether gravel needs to be removed to reduce the risk of flooding.
Periodic inspections are carried out in key areas by the Manx Utilities Authority, although it does not routinely dredge rivers.
MUA chairman Dr Alex Allinson was asked in the House of Keys on Tuesday whether Silverburn River would be dredged this year.
Dr Allinson said: ’Manx Utilities has removed gravel accumulation from the Silverburn River over recent years, when considered necessary to avoid possible flood risk.
’Any dredging has to be carried out carefully to avoid environmental damage to fish spawning areas and restrict the impact to other wildlife.’
The working window is between July and September and, in preparation for that, the area would be inspected to see if gravel accumulation presented a flood risk. If it did, it would be removed.
’In addition, Manx Utilities is undertaking a more detailed review on a number of rivers to effectiveness of gravel removal on flow capacity, with respect to flood risk,’ he said.
Dr Allinson was responding to questions from Jason Moorhouse (Arbory, Castletown and Malew), who said the river area around the bridge and Rushen Abbey looked to be at risk.
He also wanted to know what the cost of any dredging would be and how it would compare with similar exercises in 2000 and 2010.
There was no specific data for 2000, but Dr Allinson added: ’The historical costs for gravel removal in the years 2011, 2013 and 2016 were £2,500, £5,625 and £5,206 respectively. This work was undertaken when Manx Utilities felt that this would be prudent to improve or maintain flood conveyance.’
Dr Allinson said the gravel levels in some rivers was highlighted after investigations into mitigating flood risks following the storms of 2015, which saw rivers burst their banks in many places.
Source: IOMToday
