There is a continued risk of flooding in Kenley, Purley and Whyteleafe as more wet weather is forecast over the next few days.
Groundwater levels have stabilised near Woldingham and are slowing at Kenley and Purley, but could rise again if there is a lot of rain this week.
The levels have exceeded those of 2001 and are expected to remain high for several months.
Flows are emerging in Carshalton Park, Sutton, and flowing along Carshalton Place, and through the Grove to the Wandle. Groundwater levels here are approaching those seen in 2001, when properties with basements were affected.
The Environment Agency (EA) is working with Croydon and Sutton councils and other agencies, including London Fire Brigade, to reduce the risk of flooding across the Caterham Bourne area.
Temporary defences remain in place in Kenley to protect the water treatment works.
EA regional manager Caroline Douglass said: “Our sincere sympathy is with those who have already experienced flooding.
“We advise communities to remain vigilant as river levels remain high across the region, bringing a continued risk of flooding across the South East. “Groundwater flooding also remains a concern as catchments are saturated following the heavy rainfall over the last few weeks.
“We are advising people not to remove sandbag defences but to leave them in place and reinforce them if needed.
“We strongly urge the public not to walk or drive through flood water and we are advising people to stay away from coastal paths and promenades as these could be highly dangerous due to large waves
“Our teams are out and about across the region, working tirelessly throughout this ongoing incident, operating gates and structures and checking that flood defences and barriers are in good working order.
“This work will continue day and night to help protect communities across the region.”
People are advised to avoid walking or driving through flood water – six inches can knock you off your feet, and just a foot of flowing water can move a car.
Care should be taken when crossing culverts or bridges as they are dangerous when flooded.
People should look out for other hazards such as fallen power lines and trees.
People can sign up to receive free flood warnings and keep up to date with the latest situation on the Environment Agency website and on social media using #floodaware.
Call the Floodline on 03459 881188 for advice and guidance about flooding from the EA or follow it on Twitter @EnvAgencySE
- Athletes fighting to stop 'hammer blow' plan to redevelop Crystal Palace national sports centre
- Croydon battalion to march in homecoming parade after return from Afghanistan
- Surge in begging arrests after police crackdown in Croydon
- Alcoholism partly to blame for woman's death in Lewisham, coroner hears
- Police investigating after man hurt in major Thornton Heath fire