How to build a cofferdam?

Building a cofferdam requires excavations of soil and other materials to create a watertight barrier to protect construction sites from flooding. The first step is to construct the outer walls of the cofferdam, either by using sheet piling or interlocking pre-cast concrete walls.

After that, a trench is dug and the walls are driven into the soil to a specified depth, depending on the water level. The trench is then filled with sand and gravel to form a base for the structure. Next, an impermeable membrane such as plastic sheeting is laid out over the base before additional sand and gravel is used as fill. Finally, the walls are secured in place with steel reinforcement rods to ensure a watertight seal.