Video shared by a resident showed a large amount of water flowing down the street after officials say a 12-inch pipe broke Sunday morning.
Some homes in the area of Highland Boulevard were flooded by the water main break.
"This morning, like I woke up and just saw the floor going up and a lot of water started coming out. I was, like, oh, my house is going to get flooded. So, what I did, I tried to get my mom to be inside and I tried to block off the water, but it seemed like more water started coming up," Hayward resident Jose Magallanes said.
Crews will be most likely work through the night to repair the damage.
Some homes are without water and Highland Boulevard was closed in both directions.