Hundreds of homes remain on flood alert as efforts are made to stop water from pouring into homes in Kenley and Purley.
The pedestrian underpass at Purley Cross gyratory system has been deliberately flooded as a way of protecting the properties.
It is acting as a secondary ‘balancing’ pond, as the overflowing primary pond at Purley Depot breached on Saturday night, with water spilling onto Brighton Road.
'Major incident' declared by Croydon Council
Croydon Council has declared the situation in parts of south of the borough as a major incident.
Harris Primary Academy Kenley is closed all week because of flooding and parents are advised to check the school website for updates.
Other schools in the area will remain open but the council says parents should make sure children are able to get to school safely.
Godstone Road remains closed between the junction of Downs Court Road and the junction of Hillbury Road and there are diversions in place.
And contractors and firefighters are working round the clock to pump and divert water away from residential areas and prevent the Kenley water treatment works from closing.
Hundreds of sandbags have been laid around the water plant to protect it from further surcharges of groundwater.
Water levels are being closely monitored and drainage channels are being constantly cleared to ease pressure.
Liz Thorne, spokeswoman for Sutton and East Surrey Water, said its staff were working on shifts around the clock to prevent water supply problems for the 48,000 homes served by the treatment works.
Flood alert for Caterham Bourne Catchment area
The Environment Agency has put a flood alert in place for the Caterham Bourne Catchment area, including Caterham, Whyteleafe, Kenley, Purley, South Croydon, Beddington and Carshalton, as there is a risk of groundwater flooding.
Caterham Bourne is now flowing along Woldingham Road, through Whyteleafe and Kenley, to Purley.
According to the EA the rate of groundwater level rise slowed recently near Woldingham but levels have exceeded those seen in 2001.
Levels at Kenley have slowed but levels are still rising steadily at Purley.
With heavy rain forecast for tomorrow low-lying roads and properties are at risk of flooding as the Bourne could overtop its banks in places.
Rubbish and recycling collections
The council says if today is your recycling collection day then you are encouraged to leave your recyclables available for collection at your normal collection point as usual.
If your area is flooded then you should leave the recyclables on your property and collections will be made as soon as they can.
Crews cannot access Little Roke Avenue/Close/Road, Sunnydene Road, Foxley Hill Road, Dale Road, Purley Vale, Cross Road, Elm Road, Foxley Gardens, Hillside Avenue, St James Road, Famet Avenue, Famet Walk, Famet Close, Lower Road and Stevens Place.
Purley Oaks household reuse and recycling centre will remain closed for the next three days at least whilst piping of water from the balancing pond at Purley Oaks Depot continues.
Alternate centres at Factory Lane and Fishers Farm are available during normal opening hours for residents to take their unwanted household items and recycling materials.
Have you been affected by the flooding? Call the newsroom on 020 8722 6353 or send us an email.
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