Longwood Gardens is one of the premier botanical gardens in the United States, touting more than 45 beautiful gardens with 9,000 different plant species spanning 1,077 acres. Longwood maintains its picturesque estate through reuse of treated wastewater effluent via spray irrigation. Because of significant use over the years, they had multiple concerns with their spray irrigation system, including the fact that the system was not fully functional. Only 1 of 11 spray zones worked, and they were unable to completely drain their storage lagoon. Consequently, they were reaching only 7 percent of their fields.

RETTEW provided surveying, environmental engineering, and geoscience services in addition to renewal of a Pennsylvania Department of Environmental Protection (PA DEP) operations permit to rehabilitate their entire irrigation system. While working at Longwood Gardens, RETTEW observed that Longwood did not have accurate electrical and process piping diagrams/drawings of their facility, and we prepared an updated set of process and instrumentation drawings. As a result of this project, not only is the client in compliance with their updated PA DEP permit, but the operations staff is now using 100 percent of the system, including all 11 zones, and can completely drain the storage lagoon. These system improvements allow the flexibility needed to better control the irrigation of the grounds and allow Longwood to continue its sustainable application of water reuse.