Following discussion between engineers in our team based on a flood map that had been put together in 2011, we came up with the following summary points.
- Manor Park area - this area has flooded in the recent past.
- Colnbrook and Poyle area – this area has flooded in the recent past.
The following areas were highlighted as being more prone to flooding than the rest of Slough, but have not flooded recently.
- Cippenham and Haymill – due to proximity to the Jubilee River.
- Parts of Wexham.
- South of central Slough – towards Windsor.
- Northern Langley – this is also subject to impending mitigation works as part of the HS2 and WRLtH schemes.
Based on the above, we discussed possible re-routing plans for the Manor Park and Colnbrook areas, as follows.
- Manor Park - the most direct route would be to take traffic onto Farnham Road and then via Park Lane.
- Colnbrook - the most direct route would be to re-direct traffic to the M4 or M25. Local roads could also be used if need be.
- Other diversion routes will be introduced at the time of flooding, as per our network availability.
With regards to mitigating the effects of increased rainfall within the areas that are prone to flooding, we discussed the following engineering good practice.
In the event of receiving a warning of severe rainfall in Slough, we would:
- outline a plan to make sure the gullies were clear of debris prior to and during the period of heavy rainfall by clearing them of water build up as required, prioritising the high risk areas. Our road gullies are regularly maintained but hisk risk areas would be given priority on our cleaning schedule
- check that trash screens on culverts are clear of rubbish and any other obstructions
- in the Colnbrook area we have installed bore holes to enable local residents to monitor the level of water themselves and inform us as appropriate.
If a flood event does occur, we will be in contact with the relevant risk management authorities and emergency services as required.
One of the long term measures we are currently looking at is the dredging of ditches to ensure all silt and debris build up is cleared and that water can flow freely. Also, we have begun placing markers at various points in front of the screens throughout Slough to enable us to monitor a rise in the water level.
Finally, after a flooding event we would document all action taken, how effective it was and incorporate the lessons learnt into this plan.