Do not lift manhole covers to get rid of water or clear trash screens along the route of the Caterham Bourne.
This is the message from Croydon Council which is asking people to leave these jobs to the professionals.
It said lifting manhole covers can cause problems further down the system and put more pressure on the different agencies working to prevent wider flooding.
And it says clearing trash screens is highly dangerous and should only be carried out by trained professionals.
Call 020 8726 6000 and choose option one if your property is being flooded or if you think a trash screen needs clearing.
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