Options to improve the Isle of Man’s defences against harbour flooding and costal overtopping are highlighted in a report published today (Monday 19 January 2015).
The Department of Infrastructure is working with flood management specialists JBA Consulting to explore ways of reducing the risks posed to towns, villages and ports.
The report’s findings will be presented to Tynwald Members later this month and local communities will be invited to play a key role in the decision-making process.
JBA Consulting, one of only a handful of companies endorsed by the UK Environment Agency, focuses on seven sites in the Isle of Man most at risk from harbour flooding and wave overtopping – Castletown, Douglas, Laxey, Ramsey, Peel, Port St Mary and Gansey.
A range of different options to protect people, properties and businesses are analysed, including:
- Raised harbour walls
- Set back walls – to prevent overtopping or flooding reaching roads or properties
- Tidal gates
- Rock armour – to break up wave energy
- Beach recharge schemes – replenishing sand at specific sites to provide additional protection
Each design is reviewed against key criteria – including the technical capabilities, impact on landscape, environment and heritage, and capital and maintenance costs – in order to determine the most effective long-term solution.
A summary of the report’s findings is provided on a site-by-site basis, detailing the existing standard of protection, the options proposed, the highest scoring option and the lowest cost option. This is available to view at http://www.gov.im/coastandwave The total cost of implementing all the preferred options identified in the report is estimated at £31.8 million.
The Department of Infrastructure will discuss possible ways forward with area MHKs and local authorities, as well as holding a series of public meetings to present the options and encourage community feedback.
Minister Phil Gawne MHK said:
‘This is a technical study to allow the Department to make an informed decision about whether investment in coastal and harbour defences can be justified and which option represents the best solution. Our current thinking is to improve the protection of vulnerable locations and try to reduce the economic and social impact of flooding, but first we want to hear the views of people living in those areas. Communities may decide they are prepared to deal with the effects of extreme weather events once every few years, rather than see their harbour walls raised or rock armour introduced into their bays.’
Extreme weather is expected to become more commonplace in future, influenced by the effects of climate change. Parts of the Isle of Man, in particular Castletown and Ramsey, were hit by storm surges and flooding at the start of 2014. There is the possibility of further disruption during 2015, although conditions later this week are not currently predicted to cause any major issues.
Minister Gawne said:
‘The Department has contingency plans in place to mitigate the immediate risks posed by overtopping and flooding. We have 20,000 sandbags filled and ready to go, along with larger one-tonne bags and other specialist defences. While this provides a certain level of local protection, we are now looking at longer-term solutions that will be resistant to the impacts of climate change for the next 100 years.’
‘Improving our coastal defences at a number of different sites would represent a significant investment, so there must be full community engagement. Subject to public and political support, we can progress the conceptual options to more detailed designs, draw up a list of priority projects and submit them for consideration into Government’s capital programme for the next five years.’
Members of the public are encouraged to provide initial feedback via their local authorities.