The Nassau County Department of Health issued a boil water notice for residents in Baldwin, Island Park, Oceanside, Roosevelt, and South Hempstead, hours after the break.
Liberty Utilities says the water main break occurred around 3 p.m. near Silver Lake Park on the border of Baldwin and Oceanside, causing a water outage for about "30,000 customers in the Baldwin/Oceanside/Roosevelt/ South Hempstead/Island Park areas."
News Copter 7 was over Anderson Street in Oceanside, where water was seen flooding the street.
Liberty Utilities say crews were immediately dispatched and they were able to stabilize the leak by 4 p.m.
Service was fully restored for customers on Saturday.
"We moved our cars, because we didn't want them. The water was pretty high at that point," said Baldwin resident Sharon Fox.
Fox watched the water get very close to her house, saying there was another break around the corner just two months ago - but not like this.
"This was different. This was, from one second everything was okay to we had a gushing stream - not a stream, but rapids in front of the house," Fox adds.
Mount Sinai South Nassau says there has been a "disruption" in water pressure at their main campus and some ambulatory locations.
"Liberty Water reports that the break was isolated and normal water pressure should resume shortly. All patients are safe and there was no impact to patient care during this time," Mount Sinai South Nassau said in a statement.
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