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The Committee received a powerpoint presentation from the Environment Agency Officers.
It was reported that during the 2013 tidal surge 20 properties had been flooded. In January 2017 5 out of 7 warning areas forecast over he severe flood warning threshold with gale force 7-9.
Flood Warning Service - 7 warning areas. Two thirds of properties registered to receive warnings totalling 66% registered.
Currently there are 13km of Riverside Flood defences which are mainly concrete walls on the quay edge. There are 8 flood compartments (parts of the town that if water breaches the wall it will reach first). There are 5,000 properties protected. Standard of flood protection is generally between 1.3% and 0.1% 'Annual Exceedance Probability'
Potential Flood Defence Problems - Corrosion of the steel quay piles. Loss of material from behind the piles and rising sea levels.
Framework for action - produced in 2011. Largely sustain the existing standard of protection for the next 100 years. 5 'Epochs' of work through to 2061.
Stage 1 'Epoch 1' 2011-2016
650m of piling replaced. 90m of piling repaired with a total cost of £28m.
Stage 2 'Epoch 2' 2016-2021
Framework for action recommended 216km of flood defences improved (mainly Runham, Tar Works Road and Bollard Quay areas) with an estimated cost of £76m for piling replacement.
To secure approval to spend money:-
- Need to reconfirm the framework for action recommendations
-Check the condition of the defences
-Review the flood risk using computer models
-Update the benefits and costs of options
-Incorporate lessons learnt from Epoch 1, greater potential for piling repair
-Where required secure third party funding
Timescales:-
-Early Autumn 2017 preferred options confirmed.
-Late Autumn/Winter 2017 obtain prices for design and construction work
-Early 2018 secure approval to proceed
-Construction 2018-2021
It was reported that the water heights in 1953 was 3.28m and in 2013 it was 3.31m.
Funding comes from DEFRA which is distributed across the Country. If there is a shortfall then other agencies/businesses ae asked for a contribution.