in what county is port mayaca, fl?
Port Mayaca (in Martin County, FL) Populated Place Profile. Port Mayaca (GNIS FID: 294590) is a populated place located in Martin County at latitude 26.986 and longitude -80.606. The elevation of Port Mayaca is 20 feet. Port Mayaca appears on the Port Mayaca U.S. Geological Survey Map. Martin County is in the Eastern Time Zone (UTC -5 hours).