CCTV investigations in London Road, Kingston found a mound of fat the size of a bus had reduced the 70 x 48cm sewer to just 5% of its normal capacity.
Thames Water has begun repairs to 20 metres of the damaged pipe and work is expected to take up to six weeks to complete.
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An action shot of a chameleon as it snares its prey with its extended tongue has scooped top prize in an animal photography competition.
Arnis Zalkalns, a 41-year-old Latvian builder, vanished a week after 14-year-old Alice went missing from her home at Hanwell.
The 14-year-old vanished near her home in west London exactly three weeks ago.