“Blue Bloods” actor Tom Selleck has been stealing water from a fire hydrant — presumably to irrigate his sprawling ranch and avocado farm in drought-parched Southern California, authorities said.

Selleck, who plays the NYPD commissioner on the hit CBS drama, has filled up a commercial water tanker at least a dozen times from a fire hydrant in Thousand Oaks, Calif., since 2013, according to a civil complaint filed by the Calleguas Municipal Water District in Ventura County Superior Court.

The legal filing was first reported Tuesday by the online legal journal Courthouse News. Selleck owns a 60-acre ranch and avocado farm in nearby Hidden Valley. Calleguas Municipal Water District wants Selleck to pay at least $21,685.55 for investigators it hired and court costs. Other damages would be determined later, according to the complaint.

The water district claims it’s documented seven times when a commercial water truck filled up at a Thousand Oaks fire hydrant before taking it into “the Hidden Valley area where the Selleck property is located,” between Sept. 20, 2013, and Oct. 3, 2013, according to the complaint.