N21 Retention- / detention ponds
Example of water retaining structure
Challenges
Climate Resilience |
Water Management |
Natural and Climate Hazards |
Biodiversity Enhancement |
Air Quality |
Health and Well-being |
Social Justice and Social Cohesion |
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Description
Retention and detention ponds are basins that store storm water to reduce flood risk during and after heavy rainstorms. Dry detention ponds fill with water during periods of heavy rain and may contain standing water for several days depending on the amount of precipitation. The water then flows into the sewer system or, ideally, infiltrates through the soil eventually recharging groundwater. If there is no heavy rainfall event, the dry detention ponds are empty and could be used as a typical greenspace. Wet retention ponds retain storm water continuously, also holding water in dry periods.
Conditions for Implementation
- Available space (e.g. enough area to flood)
- Proper soil and precipitation conditions
Similar Terminology
Dry detention pond
Dry detention basin
Wet retention pond
Wet retention basin