US Congressman Tom Tiffany has suffered minor injuries after a small plane carrying him was forced to make an emergency landing on a lake in Wisconsin.

Tiffany, the Republican nominee for governor of Wisconsin, was travelling in the plane on Saturday night when it developed a mechanical problem near Wausau Downtown Airport, according to the Marathon County Sheriff’s Office.

Tiffany said the aircraft suddenly lost power as it approached the airport while he was returning from a dinner in La Crosse County.

The plane landed on Lake Wausau, where Tiffany and the pilot were forced to swim to shallow water before emergency responders arrived.

“As the plane began to submerge, we exited the aircraft and swam to a shallow area, where we waited until emergency responders reached us by boat,” Tiffany wrote on social media.

Tiffany said he and the pilot called 911 after the plane landed.

Authorities received a report of the crash at 20:49 local time. A Wausau Fire Department airboat reached the pair about 15 minutes later, at 21:05, and rescued them from the shallow water.

Tiffany and the pilot were the only people aboard the Beechcraft K35, a single-engine aircraft also known as a Bonanza, which can carry up to five people.

Tiffany received a small cut above his right eye, according to his campaign. “God was watching over us tonight, and I am incredibly grateful to be here in the hospital with my wife, Chris, by my side,” Tiffany said.

“An experience like this reminds you just how precious life is.”

The cause of the mechanical problem was not immediately known.

The Federal Aviation Administration and the National Transportation Safety Board are expected to investigate the incident.

The sheriff’s office said the plane remained in the lake while emergency crews worked to remove it. (Arise News)