- The big picture: One of the most common elements of local stormwater management ordinances is a requirement that new development does not increase flooding in surrounding areas. But with new development comes more asphalt, concrete, and roofs. Water can’t drain through these surfaces like it can through the soil, but it still needs somewhere to go. Enter one of the most common stormwater management techniques: ponds.
- Retention ponds hold a permanent pool of water intentionally kept at a low level to capture storm run-off. The excess water can be released after the flood event ends.
- Detention ponds, or “dry ponds,” only hold water during and after storm and flood events. Similar to retention ponds, they release the excess water after the events.
- Infiltration ponds retain run-off and discharge it quickly into the ground through absorption. This strains out debris and moves water efficiently.
Where they work: The retention pond in Atlanta’s Old Fourth Ward Park has greatly reduced flooding in surrounding neighborhoods. In Houston, a converted golf course uses detention ponds to hold as many as 500 million gallons of stormwater.
- Why you need them: Stormwater ponds keep your neighborhood safe and provide aesthetic and recreational benefits that other flood infrastructure does not. The ponds installed in Atlanta and Houston also serve as beautiful parks for residents and visitors.
- Why your county needs them: Infiltration, retention, and detention ponds offer great protection for the cost of construction. Ponds also collect debris and can improve water quality.