A fierce torrent swept through Woodland Way and down to neighbouring roads, near Roffey, after it bubbled to the surface at around 9pm.
Emergency services arrived on the scene shortly after and fire crews pumped water into storm drains throughout the night.
Joan Lucas, aged 70, of Acorns, told the County Times: “My house looked like an island.
“We could hear the water running - it sounded like heavy ran - and we looked out to see all the water coming down.
“I open the door to my garage and the water came up over my ankles, and some of my property was floating.
“I called the neighbour and the emergency services, who were super.
“But it was totally out of the ordinary. We have had heavy down pours before but nothing like this.”
She added: “I don’t think I want to see any more water for a while thank you very much.”
The severe flooding even threatened closure of nearby Leechpool Primary School.
Headteacher Sylvia Forder said: “I made the decision to open after my last phone call with Southern Water.
“We got in contact with parents this morning and asked them to wear wellies as they make their way to school.
“The road here in the morning is bedlam anyway.”
Parents were alerted to any update with the school through text messages via Parent Mail.
Lisa Shorey, of Woodland Way, added: “Water was still pumping out at 12.20am.
“They told us to fill up the bath for emergency use and to flush the toilet.”
A spokesperson for Southern Water said: “We wish to apologise for the problems and disruption caused to our customers following the burst of a 14inch water main in Horsham.
“It is a priority for Southern Water to repair bursts as quickly as possible and we immediately sent crews out on site to resolve the problem. Our team has been working round the clock.
“We are hoping that water supply will be gradually restored to those affected areas by around 10-11 o’clock this morning.” (Wednesday December 14)
They estimated six properties had experienced garden flooding.
Southern Water is now investigating the cause of the burst.
The spokesperson added: “When the repair is completed and the water pressure is returned to normal, customers may notice some discolouration in their water. This is caused by harmless deposits that can build up in iron pipes and can be solved by running the tap until the water turns clear.”