The Port Mayaca Lock is a navigable lock and dam on the Okeechobee Waterway (St. Lucie Canal), adjacent to U.S. Route 441 and U.S. Route 98 at Canal Point, in Martin County, Florida, United States.

It also serves for regulating flood control water into the Everglades during hurricane season.

[4] When polluted lake water is released into the C-44 St. Lucie Canal, the water carries or can spawn algae blooms that release cyanotoxins that may cause nausea, vomiting, skin rashes, coughing, shortness of breath, and achy limbs and joints.

The lift distance between the St. Lucie Canal and Lake Okeechobee is normally 1/2 to 2 feet (0.61 m).

[3] This lock operates on Marine VHF radio channel 13.