With population increases, the traditional linear economy has become increasingly unsustainable creating environmental pressures such as climate change and resource scarcity. The Dutch government has set lofty goals to create a circular economy by 2050. The agricultural sector in the Netherlands is vulnerable to climate pressures but is also highly profitable at the cost of sustainability making circular models difficult to implement. The world's first Floating Farm in Rotterdam, NL was created to bring food production into urban areas to increase the resilience of food supply chains. The Floating Farm has worked to implement a more circular dairy farming model by reducing land use and using recycled feed.

In this study, the circularity performance of the Floating Farm (FF) dairy production process was quantified using an indicator-based circularity assessment method. Indicators were derived from the FF's self-proclaimed circular actions and calculated using derived water, nutrient, and energy balances. A typical baseline farm was identified and used to compare indicator performance for which data was available and a comparison was relevant. From the mass and energy balances and indicator calculations, gaps in circularity were identified. To help close the gaps, scenarios to improve the farm's circularity were identified and assessed for feasibility. Each scenario was added to the indicator calculations to quantify the impact on indicator performance.

The results revealed several gaps in circularity, particularly concerning water and waste management. Once through cooling is currently used in the milk processing step leading to a very high water usage and wastewater production. In waste management, the entire liquid fraction of manure ends up in the sewer leading to significant nutrient and water losses. Generally, the farming model involves a trade-off that results in a loss of self-sufficiency, particularly regarding feed, water use, and electricity consumption. This is because no feed crops are grown, and there is no space for large-scale rainwater collection or solar energy production.

The scenario investigation revealed that switching the water source of once-through cooling water from the tap to river water is feasible, greatly impacts indicator calculations, and should be the priority for the farm to improve. The other three scenarios had several pros and cons but may be better suited for future versions of the farm due to the farm's current scale and lack of operational expertise in water treatment.

Despite the farm's efforts and enthusiasm, the indicator performance for most of the farm's circular actions have room for improvement. The farm has put effort into creating a circular economy but still must make significant strides to meet its goals. On top of the scenario recommendations, it was recommended that the farm install more measurement devices to increase the accuracy of future analyses and have a clearer view of process flows to more accurately identify losses.