The stunning possibility that more than 100,000 people who live a scant few miles from the Capitol dome could go without running water for days should send a warning to the rest of the nation, experts say.

Just like too much of the system serving Prince George’s County, the networks that provide water and sewer service to hundreds of millions of Americans have grown so old that they leak constantly and face the prospect of massive breakdowns.

In congressional testimony and a series of reports, people who study the systems on which the nation relies have warned that vital water supplies are in danger of breaking down.

More than 264 million people are served by 54,000 community water systems, each built of pipes, mains, valves, pumping stations, reservoirs and water towers with life spans that range from 15 to 95 years.

That means that while East Coast colonial-era cities may have the most ancient water systems, other cities and states that developed more recently may also have systems that need to be replaced. Oklahoma, which didn’t become a state until the 20th century, has estimated that it needs to put more than $82 billion in water and sewer systems in the next 50 years.

It has been estimated that 1.7 trillion gallons of water — about 25 percent — leak from the nation’s pipes before it can reach a faucet.

The American Society of Civil Engineers projects that without a $9.4 billion investment by 2020, Americans will face regular service disruptions like the one caused by a 48-year-old water main in Prince George’s this week.

“Our nation’s water infrastructure is too often out of sight, out of mind, and people only notice it when it fails to work,” ASCE Executive Director Patrick J. Natale said Tuesday. “Many of our pipes right here in the D.C. area are over 100 years old. The delivery of the water suffers the longer we wait to address our aging system. Hopefully, this incident will serve as a wake-up call that America needs to invest in our water systems before more events like this occur.”

The average water pipe in the District is more than 77 years old, but many were laid in the 19th century. Emergency crews tackle more than 450 breaks in an average year.

Natale suggested that cheap water is taken for granted by most people, who pay less for it than they do any other utility.

“Current water rates do not reflect the true cost of supplying clean, reliable drinking water,” he said. “When the water is turned off, families and businesses lose time, productivity and money. The costs of inaction are far greater the longer we wait.”