The police helicopter was flown from Glasgow to the Borders and 14 officers took part, along with a dog, during the incident last September after Daniel Keegan dialled 999 on his way back from a nightclub. He claimed to have seen a pair of feet disappear over a bridge parapet and into the Gala Water in Galashiels.
Officers used search lamps but found no trace of a body and they could not trace 20-year-old Keegan, either despite ringing his mobile phone and visiting his home in the town.
When contacted later, Keegan confirmed his story to police, but he contradicted himself in his statement and gave only vague details.
Keegan pleaded guilty at Selkirk Sheriff Court to wasting police time. He admitted having suicidal thoughts and was going to jump off the bridge and made the call so the police would look for him.
The court heard he had been drunk at the time, had suffered depression and had split up from his partner.
Sentence was deferred until next month.