1998 World Monuments Watch
Just beyond the boundaries of the world's oldest botanical garden, a large apartment building with an underground garage is being constructed. Since the garden's establishment by decree of the Venetian Republic in 1545, its inventory of specimens has been among the world's most extensive and rare, and today it has a seed exchange program with 693 botanical gardens. During the eighteenth century, the landscape was embellished with fountains, statuary, masonry greenhouses, and wrought-iron work. Nearly 6,000 plants are currently cultivated on the site. Even though some of the delicate plantings have endured for centuries in their original circular (Hortus conclusus) plan, their abilities to regenerate are threatened. Because of the adjacent construction, plants are showing evidence of stress from resulting changes in the water table, especially trees with superficial root systems.Subterranean pumps and changes to natural ground water levels are anticipated. The installation of a soil moisture monitoring system in the garden would resolve one of the major long-range threats to this historic garden.
Since the Watch
Shortly after Watch listing in 1998 the site was inscribed on the World Heritage List. With international assistance, a drainage and irrigation system as well as a pumping, pressurizing and desalination plant were installed. The system monitors soil moisture and the level of the water table at multiple locations in the garden, and can instantly compensate for deviations by adjusting the flow of water. January 2011