They are thought to have been caused by a collapsed Victorian clay sewer pipe found 1.5m (5ft) underground.

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This means selling things like sewer pipe and roof trusses.

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Until now, households have typically had to fix problems affecting the initial stretch of pipe that connects their property to the sewer mains.

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The material then bonds to the inside of the pipe and the resin cures or hardens, creating a new pipe within the pipe and restoring the integrity of the drain or sewer.

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