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How to Build a Wood Seawall

By Cameron Easey ; Updated September 21, 2017

A seawall is a barrier that is constructed to prevent water from eroding the front of property that sits on a body of water, such as a lake. Typically, a seawall is installed during fall or winter as some lakes that are water-controlled have their water level lowered. Seawalls are can be constructed of materials such as stone or concrete. However, you can also build a seawall using water-resistant wood boards.

Determine where you want to build the seawall along the edge of the water. Place stakes in the ground where the seawall will be located. Tie a string onto each stake to indicate the position of the seawall.

Dig a hole for the metal posts with the post hole digger to a depth of 24 to 36 inches. Repeat this step to dig a hole every 5 to 6 feet along the length of the wall.

Insert a metal post with threaded studs into each hole. Mix concrete in wheelbarrow by following the instructions on the package. Fill the hole with the concrete using a shovel. Allow 24 to 48 hours for the concrete to dry.

Place a level on top of each post to ensure that each post is sitting level to the ground.

Measure each 2-by-12 board and make a mark where the mounting holes need to be located using the pencil. Drill mounting holes into the wood with the power drill.

Place the 2-by-12 boards over the threaded studs on the metal posts. Place a washer over the threaded stud and then hand tighten a nut. Tighten the nut on the stud with the socket wrench. Repeat this step to install the remaining wood boards for the seawall.

Place a layer of rocks or gravel at the bottom front of the wall to prevent erosion. Add gravel or rock as a back fill behind the seawall and then add topsoil.


Things You Will Need

  • Stakes
  • String
  • Post hole digger
  • Metal posts with threaded studs
  • Concrete
  • Wheelbarrow
  • Shovel
  • 2-by-12 cedar boards
  • Pencil
  • Power drill
  • Washers
  • Nuts
  • Socket wrench
  • Rocks
  • Gravel
  • Topsoil


  • If the edge of the lake is tough dirt or gravel, you can dig a hole using a jackhammer.

About the Author


Cameron Easey has over 15 years customer service experience, with eight of those years in the insurance industry. He has earned various designations from organizations like the Insurance Institute of America and LOMA. Easey earned his Bachelor of Arts degree in political science and history from Western Michigan University.