David Clabo

David Clabo, this year’s awardee in the business category, has made wetlands creation and restoration an integral part of a job many would not readily associate with conservation. Clabo is currently Memphis landfill district manager for Browning-Ferris Industries (BFI). In 1988, BFI purchased the North Shelby County landfill site outside Memphis, which Clabo and BFI have turned into a unique and creative restoration effort designed to enhance wetlands habitat and wildlife protection. Clabo and North Shelby site manager James Endress have created a wildlife refuge amidst a 959-acre working landfill that represents the first of nine such restoration projects BFI has planned for properties around the country. Because only 50 acres are actively used for filling at any one time, Clabo designed a flexible development plan for the unused acres.

When it opened in 1988, the North Shelby Landfill was bounded by a creek, agricultural land, and an industrial park. Clabo first set aside 300 acres as a buffer zone around the perimeter to help insulate the refuge from adjacent land-use impacts.

Next, Clabo stopped all farming operations on the landfill site, and began a program of planting a wide diversity of plant species to stabilize the soils and provide as many different wildlife habitats as possible. Because of the tendency of the site to retain water, Clabo devised a way to manage excess water both to make landfilling possible and to benefit wildlife. The soils on the site are primarily silt loams with a relatively high water-holding capacity, and the area receives almost twice as much precipitation each year as it loses through evapo-transpiration. This amounts to 2.5 million tons of surplus water entering the landfill each year that must be managed both to stabilize the soils and protect the wetlands in and along the buffer zone.

As soon as all the row cropland was covered with vegetation, Clabo set about developing water sites for the wildlife program. He designed a plan for the site that would provide a variety of habitats, including a 25-acre lake and a 359-acre tract dedicated permanently to the wildlife enhancement program. Clabo and his staff have developed a program in which each sedimentation pond is scheduled to become a wetland as BFI moves from one active landfill area to the next. They will develop a minimum of 40 acres of wetlands at the North Shelby landfill during its operation, and plan to institute a similar pattern of rotation at the nearby South Shelby landfill as well.

Clabo and his staff are now developing four types of wetlands in addition to their work on the open water impoundments that consist of marsh areas dominated by hydric herbs, such as cattails, smartweed, sedges, and reeds; swamps dominated by bottomland trees, such as cypress, tupelo, and soft maples; savannahs in which bottomland tree species are separated by open spaces containing marsh-type plants; and open water areas surrounded by marsh and swamp species.

The open water habitat will contain a greater depth of water to ensure a year-round fishery during the late summer and early fall drought season. The 25-acre lake will feature four islands that provide habitat and protection from predators for waterfowl and other bird species. As each section of the landfill is closed, Clabo and Endress design a use for that section to enhance wildlife use and biodiversity.

While Clabo has spent many of his own hours at work designing and implementing his master plan for the landfill refuge, he has also made theproject accessible to the entire community. Clabo has invited area biologists, high school classes, Boy Scout troops, and other community residents to help plant trees, build duck nesting boxes, and work on other projects for the site.

— B.J. Hambers, Memphis District Manager’s Staff, Browning-Ferris Industries