Two burning boats blocked a Shepperton weir, putting nearby homes at risk of flooding early this morning.
Shepperton Weir lock keeper Steve Newman spotted the two boats in flames about 4.30am. Mr Newman had been woken by a rising water alarm, sounded when the two vessels became trapped in Weir A.
The flames spread to the weir structure before being extinguished by Surrey Fire Brigade. Ian Tomes, flood risk manager for the south-east Thames region, said one of the boats had sunk in the weir.
"Water levels were already high in the river due to excessive rainfall and with more rain forecast today and tomorrow, removing the boats from the weir is a priority," Mr Tomes said.
"We have used the newly finished radial gates on Shepperton Weir B slightly ahead of schedule to cope with the Thames flows. "This allowed us to remove one of the boats quite quickly.
"The second wreck, which sunk to the bottom of the river, was blocking four of the Weir A gates. "It has now been investigated by divers and removed by a team of experts, using grappling equipment and tug boats.
"This is a very serious incident which could have caused severe implications for houses upstream of the weir, potentially causing flooding to properties. "It is fortunate that we have been able to use the new weir to control the rising water levels and that public access across the weir structure to the island has not been compromised.
"The incident has been reported to Surrey Police, who are investigating."