Aurora unveiled a new 911 emergency citizen notification system today designed to alert residents via cell phones, land lines, texts or faxes when a tornado threatens to rip through the city or a major fire forces the evacuation of a certain neighborhood.

The $150,000 enhancement to the city's emergency communication system comes as Aurora seeks to keep pace with the technology most people are now using to communicate.

Increasingly residents are ditching traditional landline phones and using their cell phones as their primary number, making it difficult for cities such as Aurora to notify cell-phone users of emergencies, said Mike Biddwell, manager of the Aurora's Communication Center.

More than 75 percent of all 911 calls made to Aurora's dispatch center now come from cell phones. Roughly half of the city's residents, 150,000, continue to use landline telephones.

"Only 25 percent of the 911 calls received are from land lines," said Biddle. "To have an effective reverse 911 system we have to have a way to communicate with everyone."

Residents with landlines will automatically receive alerts.

For others to get reverse 911 alerts, they must register their cell phones, business phones, fax numbers and personal or business e-mail addresses with the city.

"The service is free. It's secure information. We won't use it frivolously," said Elizabeth Rehwalt, Aurora Public Safety Administrator. "We will only utilize (contact information) when we need to inform the public for their own safety."

Aurora also envisions using the notification system to notify residents of road closures, construction delays and citywide events.

The new system is designed to pinpoint notifications based on a certain geographic area.

For example, if there's a police stand-off in a southeast Aurora neighborhood, reverse 911 calls will be made only to residents living in the area, said Nanette Coats, a communication supervisor for Aurora.

"If we need to isolate an area, we can exclude all other areas," she said. "The neat thing about this system is that it is simple and straightforward. It's a way to get information to citizens."

To register go to www.auroragov.org; click on City of Aurora (911) Emergency) Opt in Web page link.