Northampton's Debenhams will be closed today so a flooded restaurant area can be drained.
Northamptonshire Fire and Rescue service attended The Drapery store this morning.
An employee of the Drapery store, who wanted to remain anonymous, said: "We've got electricians on site, we are now waiting for the water extraction team to drain the water out.
"It's flooded our general office where our servers are.
"When the team came to unlock they realised there was a problem. The fire service was here this morning. It started around 2 am.
"Unfortunately we'll have to let down a lot of customers today."
A spokeswoman for Northamptonshire Fire & Rescue said: "We were called at 6:09 am. Some flooding caused a malfunction on a saline solution machine."