Coquitlam Fire Chief Wade Pierlot says the call came in from the work site at Pinetree Way and Lougheed Highway at 1:45 p.m PT.
"He'd been injured by a malfunctioning piece of machinery he was operating in the trench and he'd been partially moved to an unsafe location," said Pierlot.
Pierlot said the man was a contract worker hired by the City of Coquitlam to work on services in connection with the Evergreen Line and wasn't working directly on construction of the line.
Due to the man's location within the trench, Pierlot said getting him out proved challenging.
"Those types of trench areas, once they've been injured in those there's only trained people to go down and perform those rescues," said Pierlot.
Eventually he was safely retrieved and taken to hospital for a non-life threatening lower-leg injury. Pierlot said he's in good condition.
Work Safe B.C. is now investigating the incident.
Construction on the new line has resulted in a few mishaps over the past few months. More recently, a fourth sinkhole along the line caused a major road to be closed to traffic.
In March 2014, one of the large concrete tracks shifted, causing a major traffic shutdown.