Thank you for your letter date 18th September 2011, please find answers to your questions in order below:

1. The proposed flood defence improvement scheme will not increase the frequency of flooding from Bitter Beck. The flooded area associated with Bitter Beck has been modelled with and without the defences in place and it makes no difference to the flood extents. We will also place flap valves on any drainage outfall on Bitter Beck which pose a flood risk through backing up.

2. The proposals for the flood defence improvement scheme involves raising flood walls to a level that will provide protection only up to a level that has a 1% chance of being exceeded in any year. In higher order floods the defences will be overtopped and thereafter any increase in hydrostatic loading due to the new defences will be limited. We have already carried out a visual structural inspection of the properties and from this a programme of waterproofing and strengthening works will be incorporated into the scheme.

3 During the design of flood defences we routinely make an assessment of all the potential flood pathway which increase the risk of flooding to the area we area trying to protect. These can include; seepage, drainage networks and overland flows, where necessary we incorporate measures to control these within our designs.
4 The scheme will not increase the frequency at which the water enters into the basement of HSBC Bank. We will consider whether the raising of flood defences will mean that more water passes into the basement of the Bank and if necessary we will incorporate appropriate control measures into our design.

5. The situation here is similar to that described in our response to question 2. As we are only raising flood defences to a 1 in 100 year level (1% AEP), our modelling shows that at this level the parapet walls will not be acting as flood defences. The proposed scheme will not increase the loading on Cocker Bridge beyond that which it was able to withstand in the November 2009 event.

6. During the design of the new defences we will assess the potential impact of increased flows through Cocker Bridge, including additional scour problems. We will ensure our works do not exacerbate the current level of risk of scour at the structure and if necessary scour protection measures will be carried out in consultation with Cumbria Highways.

7. The soffit level of the arch at Cocker Bridge is at a level of 45.73OmAOD. The road level at the bridge is around 46.25mAOD with the minimum level of the wall parapet is 47.35mAOD.The design levels including 300mm freeboard for each event at the upstream face of Cocker Bridge are as follows (annual exceedance probability AEP);

• 1 in 25 Year Event (AEP 4%) 45 .494mAOD
• 1 in 50 Year Event (AEP 2%) 45.886mAOD
• 1 in 75 Year Event (AEP 1.3%) 46.131mAOD
• 1 in 100 Year Event (AEP 1%) 46.3O4mAOD
• 1 in 200 Year Event (AEP 0.5%) 47.138mAOD

8. We have not taken any decisions to create “sacrificial areas” of the town. Market Place has not been designated as “sacrificial”. However, it is not our intention to defend the Riverside Car Park downstream of South Street Foot Bridge.

9. We have had the first of a series of public drop in sessions to obtain the views of Cockermouth residents on design alternatives to inform the developing design. We want to produce proposals that are acceptable from aesthetic, performance, environmental, technical and affordability perspectives. We are endeavouring to strike the balance that you describe and will be meeting again with residents of Rubby Banks Road. Once we have consulted widely we will finalise our proposals and make a planning application. Everyone will have the opportunity to comment on the planning application as part of the consultation process, before the town’s elected representatives on the planning committee meet to either approve or reject the application. All the defences work together to reduce the flood risk to Cockermouth and with this in mind we are trying to utilise our available budget to deliver a scheme that everybody is happy with.

10. As part of the appraisal process for the scheme we looked at a number of options to store water upstream of Cockermouth for both the Derwent and Cocker Rivers. This included utilising the existing upstream reservoirs and creating a new storage area. On the Cocker the volume of water that would need to be stored for a 1 in 100 year event with no changes to the current linear defences would be 560,000m3, which is equivalent to 145 football pitches flooded to an average depth of 2m. The Derwent flood storage options required even more significant areas and offered no benefits upstream of Cocker Bridge on the Cocker. There are limited sites available for a storage area, and during a flood event once the area has been filled it offers no further flood defence. Furthermore, the protection against flooding is dependent on where rain falls to ensure that the storage area does actually operate. If the rain falls downstream of the storage area it will offer no flood protection and the only viable location for storage is 4km upstream. The storage option was over 3 times the costs of the linear defences.