Department of Infrastructure Castletown Tidal Flooding & Sea Defence August 2014

2002 Tide model created Storm Surge Model Flood Maps 2002 prediction accuracy mm Meters 2014 prediction accuracy mm 2

January 2014 Flooding areas –Hope Street –Back Hope Street –Springfield Terrace –Victoria Road –Milner Terrace –Athol street –Brewery Walf Tidal Overtopping –Douglas Street –The Promenade J Robinson3

January 2014 Structural Damage Damage to sea wall at St Mary’s Car Park Damage to breakwater 4

Lessons Learnt/Improvements Shortage of sandbags Poor communication –Government –Businesses, Residents and LA’s Understanding of the flooding routes Drains, Lanes, Roads Area Protection works 5J Robinson

February 2014 Improved flood protection at end of Hope Street. Gullies and manholes covered to prevent backing up. Early deployment of sandbags and increased availability Improved communication with businesses, residents and local authorities Pre-planned road closures, advertised in advance J Robinson6

St Mary’s Car Park Castletown Commissioners reconstructed the sea wall and car park –250T of temporary rock armour to protect the area –Construction of new retaining wall –Improved land drainage –Increased car parking –Viewing area being created 7

Tactical Improvements Since January 20,000 filled sandbags Flood barriers Portable flood barriers Maintenance of non-return valves to harbour Pre-planned road closures 8

Portable Flood Barriers Demountable flood defence barrier Rapidly deployed Flexible, easy connection to walls Pods fill with rising flood waters 900 mm high units No bolting or construction work needed J Robinson9

Fixed Flood Barriers Permanently fixed wall channels Lightweight aluminium panels Durable rubber seals Units locked in place with compression screws J Robinson10

Policy and Strategy Development A high level cost benefit analysis complete Investigation of defence options and budget costs commissioned J Robinson11

Up Coming Tides Tide height –10-15 August 14 –13 th - Chart 4.15 m –8-12 September 14 –11 th Chart 4.21 m Castletown Harbour typically lower than above This only starts to be predictable 36 hours out 12

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