Puddling (civil engineering)

Puddling is a traditional civil engineering technique used to create watertight barriers in canals, reservoirs, and earthworks by compacting clay to prevent water leakage. The process involves kneading, mixing, and compacting clay—often with water—to form an impermeable layer known as puddle clay. This method has historically been essential in the construction of canals, dams, and embankments, particularly before the development of modern waterproofing materials.

Puddling was widely used during the 18th and 19th centuries, notably in the construction of Britain’s canal network, where engineers such as James Brindley and Thomas Telford employed it to line waterways and prevent seepage. Although largely replaced by modern materials like concrete and synthetic liners, puddling remains relevant in the restoration of historic structures and some environmentally sensitive projects where natural materials are preferred.