The restoration of the pond at the Glass House began in October 2014 and was completed in July 2015. This project involved the lower landscape of the Glass House, an area constructed to the west and in a valley far below the house that is the focal point of the 49-acre landscape. A refined reinterpretation of 18th-century English garden traditions, this area comprises three interrelated elements: a pond, a pavilion, and a fountain. The dredging and restoration of the pond was the first step in the multi-phase restoration of this area of the site.

The lower landscape was the first extension beyond the original five-acre plot on which the Glass House an adjacent Brick House stand. The pond was first completed in 1957 and enlarged in 1965. The pavilion, added in 1962 and made of pre-cast concrete, has many significant design features and was the first outlying structure that Philip Johnson added to the property. It also functioned as a model for later buildings by Johnson, including Lincoln Center’s New York State Theater of 1964. The pavilion was built at 2/3 scale, which makes it appear larger than it is from the Glass House promontory. It was used mostly for entertaining and had, at one time, its own gurgling fountains and a ceiling finished in gold leaf that reflected the surrounding water. The pavilion also marked a decisive turn from Johnson’s commitment to international style Modernism toward the postmodern historicism that came to characterize much of his later work. The fountain, completed shortly thereafter, was an extraordinary and dramatic jet d-eau that reached a height of 120 feet, nearly level with the Glass House. Together, these three elements signaled the transformation of the Glass House from a house into a campus, one that was devoted to the total integration of art, architecture, and landscape.

The dredging and conservation of the pond and its ecosystem were the most urgent elements of this multi-phase preservation project. According to estimates provided by the Town of New Canaan’s Inland Wetlands and Watercourses Director in 2013, the pond, which was rapidly filling with sediment and had never before been dredged, would need to be addressed within two years or it would have reverted to a wetland. The stream that feeds the pond is a tributary of the drinking water reservoir of the neighboring city so the treatment of the pond was reviewed carefully by the Wetlands Commission and done in compliance with the State of Connecticut’s Inland Wetland and Watercourses Act of 1972.

During the main phase of the dredging process, approximately 1,600 cubic yards of mainly organic material were removed from the pond using a diver-assisted suction system. Barge mounted pumps vacuumed sand and organics into large dewatering bags which retained the material but allowed water to flow back into the pond. The dredged material was then stored on-site in these dewatering bags while water drained from them. The dredged material was removed from the dewatering bags and hauled off-site. In addition to the dredging, step pools were installed on the bed of the stream that feeds the pond to trap future sediment and debris, preventing future infill. After dredging, the pond was restored to its original size (1/3 acre) and depth (7 – 14 feet).

Project Team
Dredging – Aquacleaner Environmental, Inc. / Aquacleaner Connecticut LLC
Site preparation, restoration and Forebay Construction – Stone Ridge Excavation, LLC
Soil Scientist – Steven Danzer, Ph. D. & Associates, LLC
Landscape Architect – Tracy L. Chalifoux, R.L.A.
Forebay Engineering – TJ Engineering