Corporate Park retention basin (Stafford, Texas)

A retention basin, sometimes called a wet pond, wet detention basin, or stormwater management pond (SWMP), is an artificial

pond A pond is an area filled with water, either natural or Artificiality, artificial, that is smaller than a lake. Defining them to be less than in area, less than deep, and with less than 30% Aquatic plant, emergent vegetation helps in disting ...

with

vegetation Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic charact ...

around the perimeter and a permanent pool of water in its design. It is used to manage

stormwater runoff Surface runoff (also known as overland flow) is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when the ...

, for protection against flooding, for

erosion control Erosion control is the practice of preventing or controlling wind or water erosion in agriculture, land development, coastal areas, river banks and construction. Effective erosion controls handle surface runoff and are important techniques in ...

, and to serve as an artificial

wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...

and improve the

water quality Water quality refers to the chemical, physical, and biological characteristics of water based on the standards of its usage. It is most frequently used by reference to a set of standards against which compliance, generally achieved through ...

in adjacent bodies of water. It is distinguished from a detention basin, sometimes called a "dry pond", which temporarily stores water after a storm, but eventually empties out at a controlled rate to a downstream water body. It also differs from an infiltration basin which is designed to direct stormwater to

groundwater Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidat ...

through permeable soils. Wet ponds are frequently used for water quality improvement,

groundwater recharge Groundwater recharge or deep drainage or deep percolation is a hydrologic process, where water moves downward from surface water to groundwater. Recharge is the primary method through which water enters an aquifer. This process usually occurs ...

flood protection Flood control methods are used to reduce or prevent the detrimental effects of flood waters."Flood Control", MSN Encarta, 2008 (see below: Further reading). Flood relief methods are used to reduce the effects of flood waters or high water leve ...

, aesthetic improvement, or any combination of these. Sometimes they act as a replacement for the natural absorption of a forest or other natural process that was lost when an area is developed. As such, these structures are designed to blend into neighborhoods and viewed as an amenity. In urban areas, impervious surfaces (roofs, roads) reduce the time spent by rainfall before entering into the stormwater drainage system. If left unchecked, this will cause widespread flooding downstream. The function of a stormwater pond is to contain this surge and release it slowly. This slow release mitigates the size and intensity of storm-induced flooding on downstream receiving waters. Stormwater ponds also collect suspended sediments, which are often found in high concentrations in stormwater water due to upstream construction and sand applications to roadways.

Design features

Storm water is typically channeled to a retention basin through a system of street and/or parking lot storm drains, and a network of drain channels or underground pipes. The basins are designed to allow relatively large flows of water to enter, but discharges to receiving waters are limited by outlet structures that function only during very large storm events. Retention ponds are often landscaped with a variety of

grass Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in law ...

es, shrubs, and/or

aquatic plant Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that g ...

s to provide bank stability and aesthetic benefits. Vegetation also provides water quality benefits by removing soluble nutrients through uptake.Urban Drainage & Flood Control District
Denver, CO.
Urban Storm Drainage Criteria Manual. Volume 3, Structural BMPs.
In some areas the ponds can attract nuisance types of wildlife like ducks or Canada geese, particularly where there is minimal landscaping and grasses are mowed. This reduces the ability of

fox Foxes are small to medium-sized, omnivorous mammals belonging to several genera of the family Canidae. They have a flattened skull, upright, triangular ears, a pointed, slightly upturned snout, and a long bushy tail (or ''brush''). Twelv ...

es,

coyote The coyote (''Canis latrans'') is a species of canine native to North America. It is smaller than its close relative, the wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecological ni ...

s, and other

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill ...

s to approach their prey unseen. Such predators tend to hide in the cattails and other tall, thick grass surrounding natural water features. Proper depth of retention ponds is important for removal of pollutants and maintenance of fish populations. Urban fishing continues to be one of the fastest growing fishing segments as new suburban neighborhoods are built around these aquatic areas.

Other meanings

A retention basin can also be a part of a

nuclear reactor A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nu ...

used to contain a core meltdown.

References

External links

Virginia retention basin standards
– Harris County, Texas Flood Control District

– University of Florida
International Stormwater BMP Database
– Performance Data on Urban Stormwater BMPs {{Authority control Environmental engineering Hydraulic engineering Hydrology Infrastructure Stormwater management

Design features

Other meanings

See also

References

External links