A utility provider facing multiple lawsuits over a deadly steam pipe explosion says the city may be to blame for the blast, according to a court filing.

A notice of claim filed by Consolidated Edison says the July 18 explosion, which left a woman dead of a heart attack and injured about 40 people, "may have been caused, in whole or in part, by acts or omissions of the city."

Con Edison said city sewers, pipes and drains may have let water leak onto the steam pipe, touching off the explosion after the cool water hit the hot pipe.

Filing a notice of claim is the first step toward a lawsuit. But Con Edison spokesman Michael Clendenin described Monday's filing as "a routine procedural matter, necessary in the event the investigation determines that the city's infrastructure contributed to the steam rupture."

City lawyers were reviewing the filing Tuesday.

Relatives of the woman who was killed, Lois Ellen Baumerich, also filed a notice of claim with the city Monday, saying they intend to sue for $50 million.

The claim accuses the city and Con Edison of "gross negligence, recklessness, willful indifference and outrageous misconduct."

City spokeswoman Kate O'Brien Ahlers said city lawyers were awaiting the legal papers from Baumerich's family.

The steam main exploded near Grand Central Terminal, creating a colossal geyser that swallowed a truck, tore a 25-foot-deep crater in the street, burned bystanders and showered the neighborhood with toxic debris.

The city is facing at least 242 claims — seeking a total of $600 million — related to the steam explosion, according to a spokesman for city Comptroller William Thompson.