When the Philadelphia Zoo set out to reduce its environmental footprint, plans were made to cut unnecessary water consumption. This included restructuring water use at the zoo’s historic Bird Lake, a manmade lake with no natural water source.
Zoo officials wanted to reduce dependence on municipal water, and it became apparent that Bird Lake used a lot of it, requiring fresh water daily to minimize algae growth and maintain water quality. In addition to conserving water, the zoo also hoped to communicate the importance of wetland habitat ecosystems to the public.
The zoo chose to build a system that not only filtered water, but also recirculated it in the manner of a natural wetland. Engineering firm Paulus, Sokolowski & Sartor designed a system that takes 400 gal of water per minute from Bird Lake, disinfects it with ultraviolet treatment and returns it to the lake through an aerating fountain and wetland constructed for final filtration. In addition, the new system is designed to divert rain that falls onto the roof of nearby McNeil Avian Center into the lake.
The ultimate goal of the project was to integrate a water treatment facility into a public zoo setting and to use that facility as an exhibit that showcases the natural ability of wetlands to treat water. By filtering water through beds of wetland plants, the zoo can now easily recirculate water in Bird Lake without continuously adding new water.
Since its completion in early 2011, the renovated area surrounding Bird Lake has received positive comments from zoo visitors