(CBS News) -- Americans make an estimated 240 million calls to 911 every year. As of now, text messages to 911 go unanswered virtually everywhere in the country. One city in Iowa is trying to change that.
The Black Hawk County 911 call center in Waterloo, Iowa, answers more than half a million calls a year.
Since 2009, it also receives text messages -- the first in the country to do so.
In 2011, dispatcher Amber Chase saw this text: "I want 2 kill myself...will u pls help me?"
While exchanging text messages, Chase was able to send police.
"He legitimately wanted help, and so he was very easy to get answers out of," she said.
Iowa is one of only a handful of states where people can text 911.
During the 2007 Virginia Tech massacre, students hiding from the gunman tried texting 911 operators. Their messages went nowhere.
"There are definitely situations where people can't talk -- or it's much better if they don't talk," Chase said.
Chase's colleague received a text from a domestic violence victim hiding in her home, who made this quiet plea for help:
"Boyfriend punched me... He would hurt me more if I call."
Police arrived and arrested the man.
Critics say the cost to upgrade 911 systems to handle text messages is too high and that operators fear they will miss clues in the caller's voice or from background sounds.
"There is something about talking to someone that you can just gauge them better. And sometimes just lead them better," Chase said.
But Chase firmly believes in 911 texting.
She saw the proof, she says, when she intervened in the attempted suicide.
"It just worked out perfectly," she said. "I was just able to text it to him, and that's what he needed at the time."
The trial project got the attention of the FCC, which now wants 911 texting nationwide. The major carriers have committed to make it happen by this time next year.
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