Magnum PI Tom Selleck Credit Alan Light

Magnum PI star Tom Selleck (Flickr: Alan Light)

Actor Tom Selleck has been stealing truckloads of water from a hydrant for his 60-acre ranch and avocado farm in California, according to a lawsuit filed by a water district.

The Magnum PI star and his wife Jillie Mack are accused of dispatching a white truck to a neighbouring valley at least 12 times since 2013 to retrieve gallons of precious water, which is in short supply in California due to a drought.

To catch him, Calleguas Municipal Water District (CMWD) has spent $22,000 on a private investigator, the Sun Sentinel newspaper has reported.

But even after they were issued with a cease-and-desist notice, the lawsuit claims, the Sellecks continued to take tankloads of water from Thousand Oaks to bring back to Hidden Valley in Westlake Village, where they have lived for 30 years.

CMWD is asking for $21,685.55 to cover the cost of its private investigator, a profession made famous by Selleck during his stint as Thomas Magnum on Magnum PI, plus legal costs and an injunction.

It comes as Californians are asked to cut their use of water by 25 per cent as the city grapples with an historic drought.