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A sub-surface dam is built across an aquifer or drainage route from an impervious layer (such as solid bedrock) up to just below the surface. They can be constructed of a variety of materials to include bricks, stones, concrete, steel or PVC. Once built, the water stored behind the dam raises the water table and is then extracted with wells.
A beaver dam or beaver impoundment is a dam built by beavers; it creates a pond which protects against predators such as coyotes, wolves and bears, and holds their food during winter. These structures modify the natural environment in such a way that the overall ecosystem builds upon the change, making beavers a keystone species and ecosystem ...
A detention dam is a dam built to catch surface runoff and stream water flow to regulate the water flow in areas below the dam. [1] Detention dams are commonly used to reduce the damage caused by flooding or to manage the flow rate through a channel. [2] Detention dams can also be constructed to replenish groundwater and trap sediment. [2]
The concern is they have outlived their usefulness and climate change could bring storms they were never built to withstand. Recent floods heighten concerns that New England dams may not be built ...
A sand dam is a reinforced concrete wall (or a similarly robust and impermeable weir) built 1–5 metres high across a seasonal sand river.. When it rains the dam captures soil laden water behind it – the sand in the water sinks to the bottom, whilst the silt remains suspended in the water.
The nearly 8100 major dams in the United States in 2006. The National Inventory of Dams defines a major dam as being 50 feet (15 m) tall with a storage capacity of at least 5,000 acre-feet (6,200,000 m 3), or of any height with a storage capacity of 25,000 acre-feet (31,000,000 m 3).
Embankment dams come in two types: the earth-filled dam (also called an earthen dam or terrain dam) made of compacted earth, and the rock-filled dam. A cross-section of an embankment dam shows a shape like a bank, or hill. Most have a central section or core composed of an impermeable material to stop water from seeping through the dam.
By general definition, a dam is a barrier that impounds water or underground streams, hence tailings dams are relegated to a separate list. Data on volume of structure is not as easily available or reliable as data on dam height and reservoir volume.