The grime fighting FAT detectives

Every year 'fatbergs' cost water companies millions of pounds to clear.

They're build-ups of fat, oil and grease that block drains.

But fear not, because there's a detective on the streets who "nose" how to sniff out the problem.

Hector, a nine-stone former police dog and his owner Steve Williams, have swapped a life fighting crime to one fighting grime.

They go by the name of the FAT detectives - a badge they wear with pride.

Check out Martin's report.

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