Will floating farms solve land shortage?

With land at a premium, one Dutch company has taken the innovative step of creating a sustainable floating farm

Author:

Minke van Wingerden

19 March 2020

Q: What is the floating farm?

MvW: In May last year, 32 cows boarded a new floating home in Merwehaven, Rotterdam. They have now settled in and are providing milk, yogurt and other products in an on-site shop.

Q: What problem were you trying to solve?

MvW: The problem was a lack of arable land. Sea levels are rising and land is flooding, so we started looking into using the water as a place to produce fresh food. The farm is also about making citizens more aware of food production and that it's not ecologically sound to throw food away. In addition, if you produce locally you consume locally and reduce food miles. Another theme is applying the principles of the circular economy in the city to see just how sustainable we can be.

Q: Was sustainability important to you?

MvW: We have tried to make the project as sustainable as it can be. Our initial idea was to use LEDs to grow duckweed or grass fodder on the floating farm for our cows. We researched it with Philips, but soon realised we would never be able to produce enough and it would be prohibitively expensive. Instead we looked at re-using residual products – we don't call it waste – from the city, and now we feed the cows beer broth from a local brewery, potato peel from a crisp factory, bran from a local windmill and grass from golf courses and sports fields in our area. We want to create a circular economy around the farm. We also use electric cars to pick up the food.

Q: Can you describe the farm and how it works?

MvW: The floating farm is on three layers, with the cows on top. A robot collects their manure, which is dropped down to the level below, where we separate it into in dry and wet. When we started, we re-used the dry part of the manure as bedding for the cows; however we now have rubber mattresses for them, which are easier to keep clean. We are also working with Delft University of Technology to create fertiliser from the manure to sell on. We separate the salt and minerals from the urine and water, and we are working towards treating and then re-using the water on the farm. We also use floating solar panels next to the farm, while on the roof we collect rain filter it and use it as drinking water for the cows.

Q: Are there any issues with having cows on the water?

MvW: Animal welfare is a priority for us, so we have a small meadow next to the floating farm and the cows can wander in and out of it. Nevertheless research shows that its not necessary for their welfare; all they need to be healthy and happy is sufficient space, a clean and flexible floor, water, and food.

Q: Whats next for the floating farm?

MvW: We are already talking to Asian countries to see where our next farm might be sited. It would be bigger, as the concept is easy to scale up. It was a coincidence that we started with cows, but I think it was useful as it brought us a lot of media attention. However, we have already designed a floating chicken farm and a vertical farm to grow vegetables and herbs.

Q: Who have you been working with?

MvW: We made it happen thanks to more than 40 partners who have provided knowledge and skills, as well as practical help and equipment. It's amazing to see lots of farmers who started as sceptics become enthusiastic ambassadors. We currently have 35 cows but we can easily expand that number once we are fully operational. We imagine that there will be a hybrid system where there are still dairy farms on land combined with some floating farms. We also have a team of eight, including a farmer, someone in the dairy, and a host for educational visits. People can come in and buy their produce direct from the shop and visit the farm at the same time.