How to Use Railroad Ties for Pond Retaining Walls

Dig out a rough area in which you want to create a pond. The minimum depth for this hole is equal to the thickness of one railroad tie, but the maximum depth can be any number you prefer. A typical railroad tie is 7 inches thick. Most people will choose to dig a hole that is deep enough to merit a wall needing several railroad ties. It will be helpful, but not absolutely necessary, if the pond is dug to a depth that is a multiple of 7 inches.

Flatten the bottom of the area that you want to be the bottom of the pond.

Pour 1 to 2 inches of sand on the bottom of the empty pond and rake it over the surface uniformly.

Create the perimeter of the pond by laying railroad ties along the edge of the empty pond at the bottom. Cut the ties to the size you want using a chainsaw.

Lay a second layer of railroad ties on top of the previous layer, but this time start setting the railroad ties back a few inches in an outwardly direction, away from the center of the pond. This enables you to form a slope. The number of inches by which you set the second course of railroad ties back depends on how steep you want the pond walls to be.

Drill holes through the railroad ties with a 3/8-inch drill bit. Space these holes every 1 to 2 feet.

Pound an 8-inch-by-3/8-inch piece of rebar through the holes that you drilled, which will connect the first course of railroad ties to the second course. Pound this in with a sledgehammer.

Continue laying courses of railroad ties, connecting them with rebar, until you have reached the ground surface or until you have reached the top height of the desired pond wall.

Fill the gap between the hole you dug and the wall with dirt.

Place a flexible pond liner inside of the railroad ties and stake down the edges to the outside of the pond using landscape ties. This will hold the pond liner in place and prevent it from sliding into the pond.