Police in the Charlotte suburb of Mint Hill said Kayla Campbell, 16, was discovered just after midnight. Investigators began draining the pond Wednesday evening.
"This morning we must release news we had hoped would not become true in this case," police said in a statement.
Investigators must now determine what happened to the teenager and what caused her death, police said. The Mint Hill department appealed to anyone who saw her Sunday between 3 p.m. and 5 p.m. to come forward.
Kayla left home Sunday afternoon, telling her parents she would be back in a few hours. They reported her missing that night.
Her family said the pond was a favorite spot for the teenager, where she liked to spend time with friends and take photographs. Her cellphone, bicycle and helmet were found near the pond earlier this week.