Urban farming in Rotterdam: an opportunity for sustainable phosphorus management? An approach for linking urban household waste management with urban farming
This research was formed during my internship at the Municipality of Rotterdam from April to December 2013. At the beginning of this 8-month journey, the author of this paper was given relatively much freedom in terms of research topic. However, the framework which it had to fit was set by the biannual project Architecture Biennale 2014. The project is specifically designed for Rotterdam in order to investigate the performance of several urban flows (energy, fresh water, biomass and food, waste, sand and sediment, information, transport of goods and people) in order to make their functioning more sustainable whilst using creative design strategies.
Out of personal interest, the author of this paper decided to focus on the food flows within the city of Rotterdam. The more specific research topic was formed deriving from this. Having set the agenda towards urban agriculture (UA), the set approach was to link this with more sustainable household phosphorus (P) management.
The issue of food production in today’s cities with their increasing populations has become a hot topic. It has long been discussed that developing urban agriculture in cities can have many benefits for the urban environment, not only in terms of growing its own food, but also issues such as developing ecosystems, job creation, improving access to healthy lifestyle, as well as local solutions to address municipal waste problems.
In this paper, urban agriculture in Rotterdam is first of all investigated via interviews which were carried in 11 UA areas. This was as important as it was to understand what is happening in those sites in general, who are the people involved, how the visited UA areas can be classified, how do they manage financially, to what extent they recycle their organic waste which is produced at sites, and what is generally their main aim of functioning.
As follows, the research concentrates on the performance of P flows from the households of the city of Rotterdam in order to make it more sustainable in connection with local urban farms. The base year for the study was selected as 2011. Flow diagrams have been drawn using the material flow analysis method. P is an essential element in our environment, being an important nutrient for plants, animals, and humans, or, simply put – without P life would not exist. Whilst large amount of our P resources are not recovered, urban agriculture creates a perfect opportunity for practicing the reuse of urban organic waste, which naturally includes P.
In the city of Rotterdam, it was investigated that 99% of the potentially recoverable P (572 tons) is not being reused on agricultural land. This is largely due to the fact that most of the organic waste is not collected separately and therefore incinerated all together with other solid waste types, as well as due to no P recovery during waste water treatment. Based on that finding the estimated demand for that P in terms of urban agriculture was calculated based on its current estimated surface area and whilst taking into account the demand needs of certain crops. The study shows that there is currently lack of urban agricultural land in the city of Rotterdam to close the P cycle. The amount of P which is thrown away in Rotterdam urban households is as significant 500 times higher of the present UA demand. Therefore, taking into account the P flow calculations which were made for this specific study, it was estimated that closing the P loop within the city would only be possible if all the green surface area in Rotterdam would be used for growing crops, and even more. This, however, requires an enormous change to the whole socio-economic urban system. In chapter 2.4 at the end of this manuscript, future suggestions for more sustainable waste management have been summarized in tables.
Out of personal interest, the author of this paper decided to focus on the food flows within the city of Rotterdam. The more specific research topic was formed deriving from this. Having set the agenda towards urban agriculture (UA), the set approach was to link this with more sustainable household phosphorus (P) management.
The issue of food production in today’s cities with their increasing populations has become a hot topic. It has long been discussed that developing urban agriculture in cities can have many benefits for the urban environment, not only in terms of growing its own food, but also issues such as developing ecosystems, job creation, improving access to healthy lifestyle, as well as local solutions to address municipal waste problems.
In this paper, urban agriculture in Rotterdam is first of all investigated via interviews which were carried in 11 UA areas. This was as important as it was to understand what is happening in those sites in general, who are the people involved, how the visited UA areas can be classified, how do they manage financially, to what extent they recycle their organic waste which is produced at sites, and what is generally their main aim of functioning.
As follows, the research concentrates on the performance of P flows from the households of the city of Rotterdam in order to make it more sustainable in connection with local urban farms. The base year for the study was selected as 2011. Flow diagrams have been drawn using the material flow analysis method. P is an essential element in our environment, being an important nutrient for plants, animals, and humans, or, simply put – without P life would not exist. Whilst large amount of our P resources are not recovered, urban agriculture creates a perfect opportunity for practicing the reuse of urban organic waste, which naturally includes P.
In the city of Rotterdam, it was investigated that 99% of the potentially recoverable P (572 tons) is not being reused on agricultural land. This is largely due to the fact that most of the organic waste is not collected separately and therefore incinerated all together with other solid waste types, as well as due to no P recovery during waste water treatment. Based on that finding the estimated demand for that P in terms of urban agriculture was calculated based on its current estimated surface area and whilst taking into account the demand needs of certain crops. The study shows that there is currently lack of urban agricultural land in the city of Rotterdam to close the P cycle. The amount of P which is thrown away in Rotterdam urban households is as significant 500 times higher of the present UA demand. Therefore, taking into account the P flow calculations which were made for this specific study, it was estimated that closing the P loop within the city would only be possible if all the green surface area in Rotterdam would be used for growing crops, and even more. This, however, requires an enormous change to the whole socio-economic urban system. In chapter 2.4 at the end of this manuscript, future suggestions for more sustainable waste management have been summarized in tables.
Reference
Kirsimaa, Kerli. (2013). Urban farming in Rotterdam: an opportunity for sustainable phosphorus management? An approach for linking urban household waste management with urban farming, Wageningen University, Wageningen, the Netherlands.