PARIS — When a new mass emergency notification system goes online, Oxford County residents with cellphones will be encouraged to enter their mobile phone numbers on the county emergency agency’s website.

A new system expected to be fully operational in the coming weeks will use the 911 database and mapping software to inform residents of local emergencies, such as tornadoes, floods, chemical spills and hostage situations via telephone calls.

However, with the increase of call screening on home land lines, some may never get the message. Phone systems requiring the caller to press a button to prove they’re not a telemarketer could block out important messages.

At a training session Tuesday morning at the Paris Fire Station, Rick Buck of CityWatch explained that when a home phone picks up, the automated message recording will play and the system will record the call as completed, even if the recipient never physically answered the phone.

Oxford County Emergency Management Director Scott Parker said anyone with a cellphone should enter his or her number in the county’s database when the county’s CityWatch website goes up April 8.

Residents can enter one home number and two cellphone numbers. Parker said for many with vacation homes in Maine and people who use only cellphones, signing up online will be the only way to receive information about disasters and dangerous conditions in the county.

Cellphone users can also opt to receive text messages.

Buck said the county’s CityWatch software will be updated monthly by FairPoint Communications with a database of phone numbers and corresponding addresses, allowing emergency personnel to notify people living by a river of a flood warning, or to warn people in a neighborhood of a hostage situation.

The cellphone database, however, is separate and will not be sorted by address unless local agencies sort them themselves. Otherwise, calling cellphone customers means calling everyone in a given town.

Each call made by the CityWatch system, regardless of whether anyone answers, will cost the county 10 cents. Parker said it’s well worth it.

He stressed that the system will be used only in emergency situations.

Parker called the system “an 80 percent solution at best,” saying it couldn’t be expected to reach everyone. “This is just one tool of many tools we have to get the word out in case of emergency.”

Still, he said, it’s an invaluable tool in keeping residents safe. The system was paid for by a $44,000 grant from the Department of Homeland Security.

The system is set to go online this week. On April 8, residents can sign up to add their cellphone numbers at the Oxford County EMA website.

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