Dambygging

Dambygging is the engineering discipline concerned with the planning, design, construction, operation and maintenance of dams—structures built to retain water or other fluids and to regulate their flow. Dams serve purposes such as hydroelectric power, irrigation, water supply, flood control, and recreation, and can influence downstream ecosystems and communities.

Dams are built in several principal types. Gravity dams rely on their weight to resist water pressure, while arch dams transfer load to surrounding rock faces. Buttress dams use a framework of supports. Many large projects use earthfill or rockfill bodies, often with a concrete face or core.

Key design factors include site geology and flood hydrology, foundation stability, seepage control, spillway capacity, outlet works, and seismic resistance. The construction sequence typically involves site investigation, foundation preparation, dam body construction, installation of spillways and gates, and careful reservoir filling with monitoring of stresses.

Dam safety involves regular inspections, instrumentation, maintenance, and emergency action plans to address risks such as overtopping, internal erosion (piping), or structural failure. Regulatory frameworks and international guidelines aim to standardize safety practices and response.

Dambygging projects can affect ecosystems and communities through habitat alteration, sediment trapping, fish passage disruption, displacement, and altered downstream flows. Environmental impact assessments, sediment management, and fish passage measures are commonly used to mitigate effects. Climate change and growing water demand have increased emphasis on resilience and adaptive management of dam systems.

Notable examples include the Hoover Dam in the United States, the Aswan High Dam in Egypt, and the Three Gorges Dam in China. International bodies such as ICOLD provide guidelines for dam design, construction and safety.