The water started flowing around one in the morning, and when residents woke up, water was still gushing out of it.
Serra Mesa residents now want to know how it could have happened in the midst of the drought, especially when they are facing additional water restrictions.
"They try and tell us how to take a shower, and look at this," said one resident.
Besides water, anger from residents flowed down the streets of Serra Mesa.
Hundreds of thousands of gallons are estimated to have spewed out of the fire hydrant during the early morning hours, and it took city crews over five hours to shut it down after it was first reported.
The city said a gate valve connected to a nearby water main broke in the morning, and crews had to drain the water main through the hydrant to get to the broken valve to repair it.
Residents said the city could do more to reuse the water they are losing.
In a statement, a city spokesman said, "While we hate losing any water, there's really not a good option for recycling water like this. Public Utilities looked at the issue a couple of years ago, but the cost of capturing and transporting the water is more expensive than the water itself."
A three year valve maintenance program is in the works that hopes to address old valves before they break in the future, but residents have come to question the city's strategy.
The city said it would take a couple of days to know exactly how much water was lost.