Investigators have not yet pinpointed the cause of the gas explosion that destroyed two buildings in East Harlem and killed eight people on March 12. Whether it was the age and decrepitude of gas and water mains, or something else, has not yet been explained. But even without all the answers, there is more that can be done to make New York and other cities safer, starting now.

Congress can give momentum to two Senate bills sponsored by Senator Edward Markey, a Democrat of Massachusetts, which seek to hasten the replacement of old, leaking natural-gas pipelines nationwide.

Beyond the obvious reason — preventing explosions — a concerted effort to repair obsolete gas pipes would also help reduce emissions that worsen climate change and save money, because when gas disappears, customers pay for it anyway. A study by Senator Markey in August found that gas customers in Massachusetts paid up to $1.5 billion in extra charges from 2000 to 2011 because of leaking gas pipelines. The cost to consumers nationwide was in the tens of billions, the study said.

The bills would allow natural-gas companies to charge customers more to expedite the costly job of upgrading obsolete or damaged pipes, but they would limit the ability of the companies to bill for gas lost to leaks. The idea is that a more efficient delivery system will save consumers money in the long run. The legislation also finances federal matching grants for state efforts to repair and replace old pipes, emulating a successful effort to modernize water-supply systems.