Biggest threat to US drinking water- Rust

Chicago, Jan 24: From an attack by militants to a decline insnow melt caused by global warming, public fears about the water supplyhave heightened in the United States.

So who would have thought the top worry among water experts turnsout to be rusty pipes? ''If you clean up water and then put it into adirty pipe, there's not much point,'' said Timothy Ford, amicrobiologist and water research scientist with Montana StateUniversity.

''I consider the distribution system to be the highest risk andthe greatest problem we are going to be facing in the future,'' Fordsaid.

Towns and cities across the United States spend more than 50billion dollars each year cleaning water sourced from rivers, lakes andunderground aquifers.

More than 170,000 public water systems are at work to keep tapwater flowing into American homes and meeting the standards of the SafeDrinking Water Act of 1974.

But after the extensive purifying process, water ends up in yourglass after traveling through pipes laid under city streets 50, 60 or100 years ago.

Those pipes -- made mostly from iron until plastic was introduced30 years ago -- span almost one million miles in the United States.

As the iron pipes corrode and break, not only does water escape, but also diseases get in, experts say.

''Investigations conducted in the last five years suggest that asubstantial proportion of waterborne disease outbreaks, both microbialand chemical, is attributable to problems within distributionsystems,'' the National Research Council said in a study for theEnvironmental Protection Agency released in December.

The amount of water lost is a sign the system is aging, experts say.

The oldest, largest cities in the country -- Philadelphia,Chicago, Denver, New York -- are all showing signs that theirdistribution systems are in need of repair, said Eric Goldstein, aspokesman for the Natural Resources Defense Council, a leadingenvironmental group.

In New York City, for example, the biggest leak in its system loses 1 billion gallons of water a month, he said.

It's that aging infrastructure that poses a rising health threat to consumers, experts say.

More than 273 million Americans get their water from a publicdistribution system. The other 10 per cent of Americans source theirwater from private, unregulated wells.

Fears about tap water quality are sparking more Americans to turn to bottled water or home filtration systems.

More than 40 per cent of American homes use some kind of watertreatment product, according to NSF International, a not-for-profitpublic health and safety group.

EPA rules require that water leaving a city's water plant betested for microorganisms like cryptosporidium and legionella thatthrive in degraded water systems.

EPA also requires tests for a slew of other contaminants,including lead, copper and arsenic, which can lead to any number ofgastrointestinal or other illnesses.

But once water has been purged of such impurities, different onescan enter the water supply as it courses through miles of old pipe.

''We estimate in the next 20 to 30 years water utilities will haveto invest 250 dollars to 350 billion dllars just to replace the pipesthat are in the ground today,'' said Jack Hossbuhr, executive directorof the American Water Works Association, the industry's trade group.

The cost of improving US water infrastructure may triple the cost of water by 2030, according to the association.

''We committed 100 years ago to build a reliable, low-cost,high-quality municipal drinking water systems. But there are noguarantees that will continue,'' said Peter Gleick, president of thePacific Institute, a research group in Oakland, California.

Reuters >