The dog paddled under the bridge
Andy McLean and Douglas Malloy swung into action after spotting the dog's owner stripping off to rescue the Alaskan malamute, Sasha.
The pair were working at Cockenzie Power Station in East Lothian.
Four-year-old Sasha was out for a walk with owner Steven Woods when she jumped over a wall and fell into the Forth.
A crane was used to get the dog out of the water
We don't really know how the dog ended up in the water, we think it fell in
The pooch paddled under a bridge, becoming confused and swimming in circles.
The workmen used their crane to lower Andy, 35, into the water and pluck Sasha to safety as Steve prepared to dive in.
Four-year old Tasha was out for a walk with owner Steve Woods
Douglas, 35, of Bathgate, West Lothian, said: "We don't really know how the dog ended up in the water, we think it fell in.
"The owner wanted to go in after the dog and was stripping off but he could have died, the water was freezing.
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Andy was in the crane basket and was lowered down to the water
"Basically then the crane driver told Andy to get in the basket and he was lowered in to the water and to grab the dog."
Steven, 26, from Prestonpans, East Lothian, said: "They did a great job."
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