Zero Run-Off for 20 Years!
The Kriegbaum Logistic Center and production facility is located in southwest Germany. This extensive Green Roof in Bondorf was designed by Stötzer + Neher Landscape Architects primarily as a nature roof for advanced water retention.
This project demonstrates over 2 decades using Green Roofs as a storm water management tool. The entire complex containing the two huge warehouses and adjacent parking areas has no (zero) run-off to the sewer system. All rainwater is retained, treated and infiltrated into the ground water on-site. All components were tested to avoid any contamination of the ground water. The infiltration water (run-off) is consistently tested for water quality. Since the project often has no run-off it is impossible to perform water tests – no run-off = no pollution.
Installation of this 14 acre green roof was a special challenge since it had to be completed within 10 weeks. This could only be achieved by having 4 state of the art blower trucks on site working constantly to apply the 10,000 cubic yards of growing media on the roof (up to 500 cubic yards a day). With a 150-ton hydraulic crane, all the other components (almost 100 truck loads / 3 per day) were conveyed to the roof area.
To increase biodiversity there are multiple locations on the roof with seasonal open water, wood locks and breeding opportunities for birds.
The project saved the building owner around 2 million Euros for increasing the water treatment plant and sewer system.
North America in contrast:
From 2010 to 2015 warehouse new construction in the US tippled from around $5 billion to 15 Billion this equals around 1000 new warehouses every year and translates to a potential of at least 1 Billion of square feet of extensive Green Roofs that could retain the volume of Lake Constance that is surrounded by three countries (Germany, Switzerland and Austria). On top of that and if these Green Roofs are done right and without irrigation, these Green Roofs would allow a controlled succession that could develop over the years to a unique habitat for many endangered species.
As the nationwide building codes require expensive engineered fire suppression systems the same building codes can require simple and highly efficient Green Roofs. Unfortunately most Green Roof or other environmental organizations don’t focus the low cost, high efficient simplicity – they focus on adding carrots or a rare native plant species to an environment that is far away from being connected to the ground.
Common sense exists as term but it isn’t in the head of most people because it doesn’t generate the attention and “individualism”.