BAGHDAD - A US-led attack on Iraq would probably devastate the country's tattered and already overwhelmed infrastructure, shutting down power to hospitals and water treatment plants, cutting off drinking water almost immediately to millions of residents in Baghdad and possibly elsewhere, and pouring raw sewage into the streets within hours, aid workers and specialists say.

Unlike the eve of the 1991 Gulf War, when Iraq's infrastructure was largely intact despite an eight-year war with Iran, the country's water, sewage, and electricity systems today are far more vulnerable, UN reports show. Even without a conflict, those services stand on the brink of collapse, a result of 12 years of sweeping UN sanctions, the aftermath of the Gulf War, and the government's questionable spending priorities, aid workers say.

They warn that the onset of a conflict, regardless of its duration, could create a humanitarian crisis.

''It's going to be horrendous for lots and lots of people,'' said a senior aid official in Baghdad and veteran of several other conflicts. ''People will be far more vulnerable to a future attack than before. They are much weaker, and they have little resilience.''

UN agencies in Baghdad are drawing up contingency plans to cope with the destruction of infrastructure, and the International Committee of the Red Cross said it has begun stockpiling medicine, tents, and water filtration units inside Iraq and in Iran and Jordan.

While there is little visible military preparation in major cities like Baghdad and Basra, Western diplomats say the Iraqi government is taking steps behind the scenes to cope with an attack.

The government has delayed repairs to some installations such as a telephone exchange in Baghdad, drawn up plans to relocate government ministries, and begun warehousing spare parts purchased under UN-supervised oil sales for emergency, wartime repairs, the diplomats and aid officials said. The items include electronics and communications equipment, elevator lifts, and air conditioning systems, they said.

The nature of a possible US attack remains an issue of fierce speculation, both in Baghdad and Washington, and the intensity and breadth of military action will probably have repercussions for both the US government and any future Iraqi government for years to come.

During the US-led bombings in Kosovo in 1999, allied planes used bombs that dropped carbon filaments on lines at power stations, shorting out the grid without destroying the facilities. Military specialists predict the use of other, more exotic, weapons. Microwaves could be used for the first time, destroying the computers controlling infrastructure systems without harming the larger facilities, said Dan Goure, a military specialist at the Lexington Institute in Arlington, Va.

Owen Cote Jr., associate director of the Security Studies Program at MIT, said it is unlikely planners will target infrastructure. ''It doesn't really do much for you in the near term in terms of hurting their military capability,'' Cote said. ''In the long term, assuming we're going to need to help rebuild the country, it's counterproductive in the basic sense.''

Though the US military has the capability to carry out pinpoint raids, a major operation to topple President Saddam Hussein would inevitably damage or destroy the country's infrastructure.

Aid officials in Iraq and many of Baghdad's 6 million residents are bracing for a repeat of the 1991 Gulf War.

The memories of that conflict - in particular, the 43 days of air strikes that preceded a US-led ground attack to drive Iraqi forces from Kuwait - are largely responsible for the deep anxiety expressed in a country where infant mortality rates have doubled, incomes have dropped to one-fifth of pre-Gulf War levels, and clean water remains the exception.

In the bombardment of more than 700 sites in Iraq, US forces struck leadership facilities, weapons plants, air defense, military forces, and communications networks - to incapacitate the Iraqi Army. But bombs also knocked out bridges, railroads, oil refineries, and electricity. That left many Iraqis without power for weeks and clean water and sewage for far longer and unleashed epidemics of typhoid and cholera.

Of Iraq's 20 generating plants, 13 were damaged or destroyed in the first days of bombing. By war's end, only two were left working that generated 4 percent of Iraq's prewar output, according to a May 1991 report by a public health team from Harvard University that visited Iraq after the war.

UN reports, based on independent assessments, estimate that electricity demand today is 6,200 megawatts. Only 4,400 megawatts are available. The deficit, although smaller than five years ago, still causes blackouts of an average of 10 hours a day outside Baghdad. A half-hour of gusty winds last week disrupted electricity to much of the capital.

Repairs on jury-rigged, rapidly deteriorating plants are steady but limited. As much as two-fifths of the supplies purchased under UN-supervised oil sales are rusting outside the plants or sitting idle in warehouses, either because other crucial components are held up under the UN approval process or because the Iraqi government cannot pay for their installation and maintenance, UN officials say.

With declining oil sales, Iraq is now having trouble even purchasing those parts allowed under new, streamlined UN procedures - a problem UN officials warn could become pronounced by the start of 2004.

''Every year, we are surprised units are still running,'' said Marcel Alberts, chief international observer with the UN Development Program in Baghdad. ''Some day, they are going to break down. Some of this equipment will never be used.''

One UN official, speaking on condition of anonymity, said if US forces target electrical transmission networks, repairs could be carried out in days or perhaps weeks - a crucial window to stave off a health crisis. If power plants are targeted again, repairs could take years, he said.

Unlike the Gulf War, Iraq has installed gas-powered generators at a handful of plants and other key installations, and hospitals have purchased kerosene refrigerators to protect perishable medicines. But another senior aid official predicted fuel supplies would last only days.

''The crucial thing is energy and electricity,'' the official said. ''That can be used for all kinds of things, not only civilian. They will knock it out. They can't avoid it. This is the scenario we are working under. There will be no fuel and no electricity.''

Most worrisome under that scenario is the impact blackouts could have on sewage and water, the official added. Sanitation and water systems, as well as hospitals, are today excluded from power cuts. But without electricity, they would be shut down in wartime, even if they are not targeted.

The UN estimates that half of Iraq's sewage treatment plants are inoperable and another quarter are polluting the environment. In all, 500,000 tons of raw sewage are still dumped into the Tigris, Euphrates, and other waterways each day, UN reports show.

Saddam City, a bleak Baghdad suburb of 1.8 million named after the Iraqi leader, provides a glimpse of the country's vulnerability.

Last year, the UN renovated a sprawling treatment plant at Habibiya, the destination for waste from 3 million people in Saddam City and other Baghdad suburbs on the east bank of the Tigris River. During the Gulf War, it was shut down, sending raw sewage into the Tigris. Even with the repairs to pumping stations, motors, wiring, circuit breakers and pipes, it can still handle just two-thirds of the waste sent its way.

In the neighborhood served by the plant, shin-high rivers of sewage run through its streets, flooding apartments and mixing with drinking water. As a stop-gap measure, residents have dug makeshift canals with trash to divert the waste from houses.

''It's getting worse. Day after day, it gets worse,'' said Karima Hamid, whose bare, concrete floors are inundated almost daily.

Hamid said she has to keep her six children from playing in the cesspools at her doorstep. She carted her furniture to an apartment upstairs to keep it dry and stores her monthly food rations with a neighbor. At times, she said, the drinking water mixes with the sewage.

''Every day we suffer,'' she said. ''But where can we go? We don't have any other place.''

© Copyright 2002 Globe Newspaper Company

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