The underpass at Purley Cross gyratory has been deliberately flooded in a bid to ease flooding pressure on homes in Purley and Kenley.

Croydon Council made the decision last night in a bid to protect around 400 homes and businesses and to keep the Kenley water treatment works from being flooded by surging water.

As the situation in the area continues to deteriorate, and with more heavy rain forecast, the decision has been taken to pump excess water away from the worst affected areas and into the Purley Cross gyratory pedestrian underpass.

The subway will act as a secondary ‘balancing’ pond, as the overflowing primary pond at Purley Depot breached overnight, with water spilling onto Brighton Road.

The decision was made by the major incident "gold command" team, comprising representatives of the council, the Environment Agency, emergency services, neighbouring authorities, Thames Water and TfL.

It will allow emergency services and council engineers to pump water quickly away from vulnerable areas and take pressure out of the water system.

Council leader Mike Fisher said: “This has not been an easy decision to take but it has become increasingly clear over the past few hours that we have no alternative if we are to protect people’s homes and businesses from being flooded.”

Croydon Council declared the situation in parts of south of the borough as a major incident on Thursday, with officers working round-the-clock to pump and divert water away from residential areas and to protect the water treatment works from closing.

Hundreds of sandbags have also been laid around 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.

Local residents and businesses potentially affected by the rising water levels have been visited by council teams and advised to be prepared. And letters have been delivered to about 1500 homes.

Regularly updated information can be found on the council’s website atwww.croydon.gov.uk/advice/emergencies/floods.

To check current flood warnings call the Environment Agency’s floodline on 0845 988 1188.

Have you seen the underpass today? Do you have any pictures? Contact mwatts@london.newsquest.co.uk