In 1978, the city of Zurich, Switzerland constructed a 20-foot tall planted Evergreen Macro Sound isolation wall to shield a populated area from traffic noise along a new 7-lane highway, which at the time was the widest highway built in Zurich, Switzerland. The Evergreen Macro wall was planted and so absorbed the traffic noise instead of reflecting it back. Also in 1978, a state road in Aargau, Switzerland was endangered by an active earth-slide. Geo-technical engineer, Dr. Felix Jaecklin, P.E. was engaged to solve the problem and then the first landslide removal Evergreen Wall was built.
The innovation of the Evergreen Wall design was a “crib” shaped reinforced precast concrete element that was produced by a local pre-caster, installed with one open end excavated into the earth-slide, and filled with available on-site materials. Each Evergreen Wall element was then filled, compacted, stacked and planted. With this resulting product, the earth-slide was quickly and permanently contained, without the time and expense of installing temporary shoring or expensive drilled and anchored piers. As proof of this system, every Evergreen Wall built and installed since is still standing and holding strong to this day.
The Evergreen Wall design was continually developed and engineered to include increased requirements in aesthetics, manufacturing plant performance, structural performance, and maximum wall height by providing ample room for plants to grow between beams and by optimizing the precast frame for economical use of reinforced concrete.
Within four decades, Evergreen Wall is now in use throughout Eastern and Western Europe, North America, Japan, South Africa, and the Middle East. Within the United States and Canada, Evergreen Walls are concentrated in the New England, Mid-Atlantic regions, and the West Coast from Southern California to British Columbia. Evergreen Wall engineers work in cooperation with local engineers and governing agencies, NPCA Certified Precast Concrete Producers, and licensed contractors to implement the Evergreen Wall design given local site soil conditions and local construction codes.
The innovation behind the original Evergreen Wall has led to the development of additional retaining wall systems such as: Evergreen GeoWall, and closed face Evergreen Macro. With forty years of global geotechnical engineering experience behind it, Evergreen Wall has now designed the MAXIWall by Evergreen system which can support (80,000-lb per axle) railway live-loads or heavy static conditions and which is setting a new high standard for efficient installation in the precast reinforced concrete and earth retaining wall industries.