Huge pumps are struggling to keep up with the continuing inflows of water from the Morwell River into the crippled Yallourn coal mine in Victoria’s Latrobe Valley.

Floodwaters collapsed an embankment three weeks ago and millions of litres have been pouring into the mine each day since then.

The water flooded conveyor belts carrying coal to the Yallourn generator and three of the four power units have been switched off.

Toby Thornton from the Construction Forestry and Mining Union has visited the site and says workers are concerned about forecast rain this weekend.

“There’s a significant amount of water there and you can just see the lamp post peering out of some sections of the water. It’s a massive amount of water there,” he said.