The infant has been identified as a boy, born about one to two weeks ago, state police said.
The mother, a Connecticut resident, came forward and spoke with detectives from the State Police Western District Major Crime unit as they continue to investigate the untimely death.
Related story: Body of dead baby found in Litchfield County reservoir
The mother, whose name was withheld at this time, has also been provided with necessary medical care at a hospital, state police said.
"It is important not to pass judgment regarding this event until all the facts have been thoroughly reviewed," state police said on their Facebook page.
The infant is believed to have been born full term, state police said.
At 10:40 a.m. Tuesday, state police troopers from Troop L in Litchfield were notified that a deceased baby was located in a bag in Bristol Reservoir #4.
The reservoir is located on Route 72 and Route 4 in the town of Harwinton in Litchfield County. The City of Bristol Water Department maintains the reservoir.
The State Police dive team responded to assist the Western District Major Crime unit and search for evidence.
The Office of Chief Medical Examiner was conducting a post-mortem examination to determine the cause and manner of the baby's death.
The City of Bristol Water Department consulted with the Connecticut Department of Health. The reservoir has not been used in a few days, and will remain offline for now.
The water department said the public water supply is safe, and it has no concerns for the safety of the public.
"Western District Major Crime Detectives thank the public for their assistance, and encourage residents to continue to help keep their community, town, and state safe," state police said.
Anyone with information on the case is asked to contact Troop L at 860-626-7900 or text TIP711 with any information to 274637. All calls will remain confidential.
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