The 48-year-old concrete main broke around 4:30 a.m. near the intersection of Birch Street and Portland Avenue in Scotch Plains.
A huge amount of water was surging down the street, and the scene resembled river flooding.
Water flooded nearby St. Bartholomew the Apostle Parish, which appears to have sustained the most damage. Workers immediately started pumping water from the church and flooded parking lot. Several buildings and basements were completely flooded out, and many cars were also under water.
Residents on several blocks were told to temporarily evacuate as the water spread.
"All I heard was the water," evacuee Barbara Barone said. "And I honestly thought it was rain, because I heard this gushing, but I didn't hear a pipe break. But I saw where it was, and I saw the water gushing out all over the place."
The line does not does not feed customers, but the break affected water pressure. Residents in Scotch Plains, Fanwood, Watchung and Warren were told they will experience low water pressure. American Water officials asked residents in those four towns to conserve water.
The broken water line was capped just before 7 a.m., but because it is deep under the street, water officials say it will be some time before they know the extent of the damage or the cause of the break.
No residents were hurt.
Local roads were closed, but Route 22 was not affected.
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