The wet ponds at the Central Park development are designed to provide a unique blend of environmental, aesthetic, and economic benefits. Another wet pond funded by the department is located on the campus of St. Edwards University on South Congress. The use of wet ponds in the Austin area has been driven by several concerns. Originally, sand filters were the standard controls required by the City to treat urban runoff. While sand filters are highly effective at removing sediment and adsorbed pollutants such as heavy metals, they are ineffective at removing dissolved pollutants such as nitrogen and phosphorus, common nutrients.
Wet ponds are as effective as sand filters at removing solids and also remove dissolved pollutants.
Wet ponds are more cost effective than sand filters and may be a multi-function facility providing water quality treatment, flood protection, stream bank erosion control, and recreational uses. Because properly designed wet ponds hold stormwater runoff for a long period of time, they allow pollutants to be removed from the water by the processes of sedimentation, microbial treatment, and vegetative filtration. Sediment and other pollutants settle out of the water and are not discharged to area creeks and lakes. The wetland plants serve as a natural filter for the nutrients and other pollutants found in urban stormwater runoff. Additionally, the ponds provide habitat for a variety of birds and animals that many people find appealing.