Joel "Jay" Arnier, a 20-year veteran, was fishing when he heard a woman screaming and saw her pull her lifeless child out of the water.
It happened around 1 p.m. outside the child's home along the Fox River in McHenry County.
"She ran straight towards the river and didn't even stop, right into the river, and there was something floating in the water and it was her daughter, a baby," Arnier told ABC7.
After convincing the frantic mother holding her lifeless little girl that he could help, Arnier's professional training kicked in.
"I started to do some resuscitation with mouth-to-mouth. It was difficult to get air in the baby because she aspirated quite a bit of water from the river," he said.
According to the McHenry County sheriff, the child got out of the house along with her two siblings in the brief moment their mother had run upstairs for something. Arnier performed CPR with mild chest compressions for three to four minutes, wishing he had professional suction devices and oxygen.
"I wouldn't have given up. I would have kept going until the ambulance got there whether she responded or not," said Arnier.
Finally he detected a small cough and the mother, who had her mother on the phone while a neighbor dialed 911, poured her heart out in a combination of fear and gratitude.
"She was very distraught, trying to get her mom to come over," he said.
In all, the child, whose name is not being released, was likely not breathing for upwards of five minutes. But when she started coming to, the paramedic said she did not have dilated eyes nor was she making head movements indicative of brain injury.
"Basic life support. That's what you do and it works," Arnier said.