DUNN, Wis. -- When a tornado strikes, mobile homes can be deadly, but a unique storm shelter project is about to change the odds of surviving a tornado for hundreds of people in the Dane County town of Dunn.

Construction begins next month on a $650,000, 3,300-square foot storm shelter sited inside a mobile home park.

The Federal Emergency Management Agency is paying for 75 percent of the storm shelter and the town is paying the rest for the FEMA-approved shelter.

Officials said it's money well spent.

In 2005, a terrifying super cell of tornados tore through the town of Dunn, destroying 69 homes along the way. One person was killed and 23 were injured, but it could have been a lot worse.

That's because the twister came within half a mile of the Bayview Heights Mobile Home Park, where families had no place to hide.

A few residents ran to a small bike path tunnel under Highway 51, but officials said that tunnel can actually suck in flying debris.

"There really is no safe place at all," said park resident Bernice Patterson.

Patterson is one of 540 people at the mobile home park -- 10 percent of the town -- and they're all at great risk of death during a tornado.

"We haven't had anybody die in the town of Dunn as a result of a tornado. But if something happens here, we will have dead people. There's no doubt about that. That's the kind of thing that keeps me up at night," Town Chairman Ed Minihan said.

But town officials and residents can sleep easier now because of a FEMA grant. It will allow the town to build a special storm shelter on a grassy field inside the mobile home park, on some land leased to the town by the park owner.

The FEMA-designed shelter is meant to protect up to 575 people against 250 mph winds, thanks to a special foundation.

"If a storm were trying to suck the shelter off the ground, the foundation would be massive enough to secure the structure. That's what's special about it," said Cathy Hasslinger, the town clerk/treasurer who wrote the FEMA grant application.

Patterson said she is relieved to hear about the shelter.

"I've got a 9-month-old granddaughter and a 1-year-old nephew in this park. I'm glad there's going to be a safe place for them to go."

National storm statistics over a period of time from 1995 to 20002 showed nearly half of all tornado fatalities were suffered by mobile home residents who stay put or try to flee too late.

FEMA said this type of shelter is one of several built in the state and in the region.

The shelter is expected to be finished by November.