1. Flood Prevention Measures The first six months of 2013 have seen a significant increase in flooding of both tertiary and machine installation. The following proposal sets out how we will tackle this issue in the short medium and long term

2. The problem

3. Point 2 External flooding

4. Bat 892

6. Causes - Not under our control More frequent high intensity storms Long periods of drought followed by storms leads to all the rain fall passing into the drainage network due to dry compacted ground Hail stones blocking the drainage network

7. Contributing factors Inadequate drainage network poor design of paved areas Maintenance Increase in paved surfaces Basic design concept for buildings

8. Actions

9. Short term In the next 4 to 5 weeks Establish a list of at risk buildings An action plan will be agreed between GS-SE, CFRS (CERN Fire & Rescue Service), TSO, and other key stakeholdersTo include: Drain cleaning Installation of retention basins to control the water. Sealing of openings where possible identifying weak points in the building such as doors cable pits and provision of sand bags to be installed in the event of flood. Provision of pumps and bagging List of “volunteers” to assist in the control and clean up in the event of flood (on a best effort basis)

10. Medium Term Year end Model the “at risk” areas and identify weaknesses in the network Campaign of down pipe replacement (putting them on the outside of the buildings) Modify and repair the drainage network

11. Long Term Establish CERN specific design guides for building design and roads and paving