"He said that he inadvertently left the box on the bumper of his truck. The box fell off his bumper while he was driving north on Beacon Boulevard, sending the cash across the roadway just south of the bridge," police said.
Police have appealed to those who picked up the cash to hand it in.
So far one woman handed in nearly $5500 while two teenagers have turned in $900 each.
According to police, more than $30,000 is still blowing in the wind, or yet to be returned.
"Thank you and way to go! We commend you for your honesty!! The owner of the money will be grateful," police wrote.
Facebook commenters also praised those who had returned money, with many saying it was "awesome" to see integrity and honesty when it would be easy to keep the cash for themselves.