Novo Nordisk headquarters in perfect water balance

The Danish global healthcare group, Novo Nordisk, is managed according to the Triple Bottom Line principle: The company must be economically viable, socially responsible and environmentally sound. The principle applies to all Novo Nordisk's activities; also when it comes to constructing a new billion-dollar domicile. When Novo Nordisk invited tenders for the construction of the group's new headquarters in Bagsværd, the tender material stipulated that tenderers must incorporate sustainable solutions into the construction project. At the prospect of more frequent and more powerful precipitation events in the future, rainwater management had to be an integral part of the proposed construction project.

The first sod was turned in October 2011 and the headquarters were completed and ready for use in 2014. The buildings were designed by Henning Larsen Architects and inspired by the helix structure of an insulin molecule. The headquarters comply with energy efficiency class 2015 and consist of two office buildings with underground parking occupying a total of 50,500 square metres and ringed by a 22,000-square-metre natural park (i.e. roughly three soccer fields) connecting the two buildings. The urban development and consultancy firm SLA designed the landscape architecture for the project.

In theory, the system of technical solutions is actually quite simple: The two underground basins collect rainwater from perimeter drains and from the green roofs of the buildings. The remainder of the rainwater and surface water from the park is routed across terrain and via underground channels to a large gravel cushion situated around one meter below the vegetated surface. This means the natural park can cope with water volumes equivalent to a 100-year rainfall event, without having to divert any of the water to the surrounding local sewer systems. At the same time, the sloping green roofs are overgrown with a mixture of grasses and meadow vegetation which both have large water uptakes and evaporation.

"This is in no way a super complex solution, but, of course, we experienced unexpected problems along the way, and these had to be solved. For instance, it turned out there were pipes in the planned location for the gravel cushion. There is nothing to designing a gravel cushion - until you start digging and strike pipes! But we found a solution to that, too," said Marianne Mølgaard, facility portfolio manager at Novo Nordisk. She was primarily responsible for authority permissions etc. as well as the sustainable part of the construction project.

The area around the former headquarters was paved over with asphalt and could hold 400 cars. In the new centre, cars now have to use the underground parking facilities. Parts of the underground parking facilities are located under the natural park.

"We use the water in the basins to water the green roofs and the vegetation on top of the underground parking.The roots of the plants do not reach far into the ground and, therefore, the plants have to be watered in dry summers.The part of the park that is not on top of the construction itself should be able to cope on its own.A lot of thought has been given to the park and any depressions in the terrain, so that the water is diverted to where we want it to be stored temporarily.Some paths may be flooded during a cloudburst, but none of the major paths," said Marianne Mølgaard.

Marianne Mølgaard stresses that the company's collaboration with the Municipality of Gladsaxe has been a huge advantage throughout the process. For example, the site for the new headquarters in Bagsværd was part of a contaminated site where there used to be gravel pits. In connection with the construction of the new buildings, Novo Nordisk therefore removed enormous quantities of soil, including any remains of contaminated soil. New soil was added to the construction site from another construction project in the municipality. There was therefore a mutual benefit for the parties involved. Novo Nordisk did not have to buy the soil and the municipality did not have to pay to get rid of it.

"One of the great challenges was that there is a contaminated site in the vicinity.Because we are situated within the drinking water catchment area, we had to spend a lot of effort in documenting that we would not have any major effect on the drinking water.It was a very complex issue, because we did not have any basis for comparison.Our consultants were a little in the dark on this issue and the municipalities had to help us find the right legislation and the right authorities to contact," said Marianne Mølgaard, who encourages others to involve the authorities at a very early stage.

"There is a lot of focus on water and soil in climate change adaptation, and permits are needed, almost no matter what solution you come up with.  So it is always a good idea to contact the authorities early on.This will allow you to find really good solutions and to integrate them so that they cost you as little as possible," she said.