Retention ponds or "wet ponds" are ponds constructed to treat and store stormwater runoff. Retention ponds are permanent pools of standing water and eventually empty into a receiving water body. Forebays can be included in the design of a retention pond to "pretreat" the stormwater before it spills over into the major water feature. Water is treated through sedimentation and nutrient uptake.
Benefits of stormwater retention ponds include:
- Improved water quality in surrounding water bodies. Retention ponds manage stormwater quantity and quality, lessening the transfer of pollutants and chemicals into nearby water bodies.
- Aesthetic appeal. A retention pond may enhance aesthetics via plant selection, plant placement, topography and pedestrian access options.
- Increased biodiversity. Biodiversity is defined as the variation of life forms in a given ecosystem. Landscaping with ponds and different varieties of plants can add to the natural environment.
- Wildlife habitat. Retention ponds provide habitats for animals, organisms, and insects.
- Water conservation. Water that is stored in retention ponds is available for non-potable human uses such as irrigation.
- Flood prevention. Stormwater quantity reductions minimize the risk of flooding in nearby areas.
- Minimization of erosion. Stormwater quantity reductions minimize erosion in the nearby area and along the banks of water bodies.
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