INTRODUCTION

In Rotterdam, sustainable development and responsible approaches towards climate change are crucial because of two correlational reasons. On the one hand, it is a low lying delta city with an expanded water system, so it is exceptionally exposed to rising sea levels. On the other hand, the Port of Rotterdam -the largest in Europe (^{Eurostat, 2020})- is a major producer of CO₂ emissions (^{Port of Rotterdam [PR], 2019}). These contradictory factors make Rotterdam’s case particularly interesting. They have evoked the question of how to reconcile such conflicting interests and maintain the dynamic development of the city.

The search for proper solutions has driven local authorities to create a strategy aiming to make the city sustainable. Most of municipality documents concerning sustainability were passed in 2019, in some cases replacing or updating previous ones. In the moment, Rotterdam has an extensive but coherent and up-to-date strategy. The sustainable development process is supervised by councilor of a dedicated municipality unit responsible for sustainability, air quality and energy transition.

The departure point of the municipality strategies analysis is the city’s Sustainability Compass (Rotterdams Duurzaamheidskompas) (^{Municipality of Rotterdam [MR], 2019e}). It is a tool first created in 1997 to enable common understanding of sustainability. Directions of a regular compass are renamed following well-known first letters: nature, economy, society and wellbeing (^{Compass Education, 2017}). The tool allows to easily comprehend major aspects of sustainability. In Rotterdam, the directions of the Sustainable Compass are energy transition, circularity, climate resilience and healthy living environment (^{MR, 2019e}). Through isolating given factors from the broad understanding of sustainable development, Rotterdam puts clear emphasis on the importance of these elements.

The main focus of this paper is to demonstrate sustainability strategy adopted by Rotterdam’s municipality and its presence in the city planning documents: strategies, agreements and initial outlines. Each element of the policy -energy transition, circularity, climate resilience and healthy living environment- is described and complemented with tables summarizing the targets of the sector, as well as relevant documents. Subsequently, selected documents are discussed in more detail. The paper gives a view on main aspects of Rotterdam’s complex sustainability strategy.

1. ENERGY TRANSITION

Energy transition is the most elaborated aspect of the sustainability strategy and it is directly based on various documents, as well as divided into further elements: infrastructure, clean energy sources, port, mobility and construction. It is a major challenge for the municipality and a crucial process on a national level. Due to the harborside activities, Rotterdam is responsible for one-fifth of CO2 emissions in the Netherlands (^{Verheij, 2019}), while being home for less than 4 % of its population (^{CBS, 2020}; ^{MR, 2020}). In this situation, transition to clean energy is a priority for the municipality.

City of Rotterdam aims to fulfill postulates of the Paris Agreement and limit the temperature rise to a maximum of 2 °C, compared to the pre-industrial era (^{UN, 2015}). The municipality is also obliged to meet the targets provided in the national Climate Agreement of 2019 (Klimaatakkoord) (^{CN, 2019}). These include lowering CO₂ emissions to the half of 1990 emissions by 2030. In order to make it possible, annual city CO2 emissions are supposed to be in a downward trend by 2022. The National Climate Agreement also requires disconnection of 1.5 million apartments from the natural gas network by 2030 and intends that all buildings will be heated sustainably by 2050, so the country is completely independent from natural gas. The municipality itself aims to become climate neutral by 2050 (^{MR, 2019c}) (table 1).

The basis of all of the municipality’s activities in the field of energy transition is Rotterdam’s Climate Agreement, adopted in autumn 2019. The set of documents is the result of cooperation between the municipality and over a hundred companies and social organizations. Under the leadership of independent chairmen, participants of five climate boards -Port & Industry, Built Environment, Mobility, Clean Energy and Consumption- have developed 49 so-called climate deals which provide an impulse for the low-carbon economy (^{MR, 2019c}). The Agreement aims to reduce CO2 emissions by half by 2030, compared to 2017, so under 15 mt CO2/yr (^{MR, 2019e}). The document contains proposals for large wind farms off the Rotterdam coast, the construction of a hydrogen network and the large-scale insulation of Rotterdam homes.

Within the scope of clean energy, the following documents have been adopted: Energy Infrastructure Plan, Solar and Wind Energy Acceleration Outlines, and Clean Energy Strategy. The last-mentioned indicates which sources of clean energy are available and demanded in the city. It consists of sources qualification, indication of their potential in 2050, 2030 and now, as well as a prognosis of the demand. In other words, the document provides insight into the possibilities for generating clean energy in Rotterdam, including the associated potential. (^{MR, 2019f}).

Clean Energy Strategy serves as a background for another document -Rotterdam Power System Strategy (Rotterdamse Energiesysteemvisie)- which is going to be completed in 2021. Knowing the possibilities of using clean energy sources in advance allows to prepare a strategy that meets the challenges of sustainability better. What is more, maintaining a proper order of adopting documents works for the consistency of strategic planning (table 2).

2. CIRCULARITY

The Netherlands is a major waste generator. In 2016, the country generated 520 kg of municipal waste per person, nearly 40 kg more than the EU average (^{EP, 2018}). A sustainable economy requires a well-developed waste management, which means both reduction and effective processing of remaining waste. To achieve that, Rotterdam aspires to become circular. The basis for a circular economy consists of preventing and reducing the use of primary raw materials; extending the life of products; reusing products and parts; recycling materials into raw materials (^{Murray, 2017}). It is contrary to the current linear economy where products simply devaluate and materials they are made of are wasted (^{Murray, Skene & Haynes, 2017}). Rotterdam aims to become fully circular by 2050 (^{MR, 2019d}) (table 3).

Municipal documents directly concerning circularity:

The basis of all of the municipality’s activities in the field of circularity is Rotterdam’s Circularity Programme 2019-2023. Main points of focus includes increasing circular awareness among residents and increasing activity in the circular economy and employment. The program emphasizes on aspirations in sectors of construction, green streams, consumer goods and health care. Goals aimed to be achieved by 2023 include:

Construction plays the most important role in the document. This sector includes the development, design and management of areas, buildings, infrastructure and public spaces. It is a crucial element of the strategy, as it is responsible for generating 66 % of waste in the Netherlands (^{OECD, 2020}) and the sector is expected to continue to grow in Rotterdam (^{MR, 2019d}). Its importance rests on the belief that a lot can be achieved in a relatively short time due to the low efficiency of construction today. Rotterdam’s Municipality aims to extend the lifetime of existing buildings and dismantle as many materials as possible for efficient reuse. It is to be achieved through strategic issuing of permits and mostly through promotion of circular construction. Just like circular economy in general, it translates in reducing the use of primary raw materials, reusing and recycling materials (^{Murray et al., 2017}).

Separating and collecting raw materials in densely populated cities is a major challenge due to the lack of physical space for various bins. In 2018, 129 kilograms of raw materials were collected separately per person in Rotterdam (^{MR, 2019b}). That same year, another 296 kilograms of residual materials were burned per person (^{MR, 2019b}). Raw Materials Management Outline (Grondstoffennota) postulates that households in the city will no longer produce residual waste by 2050. The first step is to reduce it to 249 kilograms per person in 2020. About 40 % of the household residual material consists of organic waste which is difficult to limit. The municipality successively provides residents with proper containers, so organic waste can be reused. The best way to reduce the amount of residual materials is to prevent their usage (^{Bortoleto, 2015}). Among other things, the document requires educational actions aiming to create awareness among residents.

3. CLIMATE RESILIENCE

Rotterdam is a low laying city with an extensive water system, situated in the estuary of the Rhine, Meuse and Scheldt rivers. It is linked directly with the North See, only around 30 kilometers down the broad waterway. Like many parts of the Netherlands, Rotterdam is significantly threatened by backflow and flooding. To prevent that, the Delta Works programme (Deltawerken) initiated in the 1950s. It is a series of construction projects aiming to protect the Rhine delta through a system of dams, dykes, etc. (^{Schaminee et al., 2019}). Rotterdam had been the weak spot of the system until the 1997 completion of the Maeslant barrier which cuts off the waterway automatically in the event of danger (^{Deltawerken Online, 2004}). As the sea level rises, solutions created several dozen years ago might not be sufficient. It’s not just a question of how to protect, but how to protect and function normally in matters of economy and social life. Greater susceptibility to floods will result in more frequent closing of barriers (including the Maeslant), thus hindering the operation of the port.

Other climate change problems facing Rotterdam include increase in rainfall, longer periods of drought and longer heat waves (^{MR, 2013}). In order to absorb heavy rainfall, long-term drought and heat interventions are required in public and private areas. At the same time, flexibility is needed to adjust the approach based on new insights. All of that is intended to make Rotterdam a climate-resilient city.

The strategy in this field focuses mainly on the challenges, needs and measures at neighborhood level. Many solutions not only have functional value (water storage) and financial value (less damage due to flooding), but also social value (^{MR, 2019a}). For example, water squares and green roofs are places where people meet, and children can play. They contribute to the quality of life and recreational opportunities in the city. Only 40 % of Rotterdam area is public land. Since creating a resilient city requires physical solutions in urban space, cooperation with private entities and residents is essential (^{MR, 2019a}).

The municipality has adopted the Rotterdam Adaptation Strategy to set the framework for the city to become resilient. The document indicates expected effects of the climate change and proposes available solutions (^{MR, 2013}). It is based on four principles:

Rotterdam Adaptation Strategy aims to protect the city and its residence from negative effects of climate change. Residents are expected to be aware of the consequences of climate change and of the action options they have. The municipality wants them to take their responsibility and contribute to the city efforts (^{MR, 2013}). The document also emphasizes on the port’s safety and accessibility, as it is a crucial part of the city’s economy. What is more, Rotterdam wants to gain profit from becoming climate-resilient, both economically and marketing-wise (table 4 and 5). It is to be achieved through new economic impulses and creating the image of a progressive, leading city (^{MR, 2013}). Actions taken as a part of climate adaptation contribute to a comfortable and attractive city.

4. HEALTHY LIVING ENVIRONMENT

Number of residents and households in Rotterdam is expected to grow at least until 2,035 (^{MR, 2018b}). Intensification of space usage might bring negative effects, including health, safety and comfort issues for residents. One of the examples is housing being increasingly realized at locations close to highways and railways, which is associated to noise. Another challenge is transforming industrial areas into new forms of use, due to possible soil contamination. Also clean air is essential for a livable and healthy city. As mentioned before, Rotterdam and its port are major CO₂ emissions generators.

Rotterdam’s municipality believes that eliminating the above-mentioned problems and creating a healthy living environment is a crucial element of the sustainability strategy (^{MR, 2019e}). It is reflected in already adopted Clean Air Course Plan and documents which are intended to be released in 2020: Noise Action Plan, Soil Course Plan and Environmental Safety Course Plan. This part of the sustainability strategy is centered mostly around residents and their needs but requires action in various fields.

The Noise Action Plan is an interesting document, as it demonstrates the importance of living comfort in the city strategy. Excessive noise exposure can lead to health problems in both the living and working environment (^{MR, 2018a}). The municipality wants to limit the impact of noise on health through a number of initiatives. Rotterdam expects to construct a total of 22.7 hectares of silent asphalt by 2024 and connect the process with the road maintenance program. It is a crucial element of the strategy, as road traffic is responsible for 93 % of noise in the city. Decreasing the noise levels of road traffic is also relatively easy to achieve by local authorities, since over 90 % of all roads in the city are municipal (^{MR, 2018a}).

In land development plans, the municipality is increasingly confronted with conflicting spatial claims, as well as competing wishes and interests between business and housing, construction and greenery, or transport and livability. This requires choices, in which creating the healthy living environment has priority (^{MR, 2019e}). Such policy stimulates the realization of high-quality public and private spaces (table 6).

Municipal documents directly concerning healthy living environment:

5. CONCLUSION

Rotterdam is heavily exposed to the negative consequences of climate change. At the same time, its economy is profoundly dependent on the work of the largest port in Europe, whose activities generate significant CO2 emissions. To reconcile these two opposing factors, the municipality of Rotterdam has developed an extensive strategy for sustainable development. The city intends to use its complicated situation to create an innovative model combining ecological, economic and social benefits, and thus also image-related. The municipality of Rotterdam divides its sustainability strategy into four elements: energy transition, circularity, climate resilience and healthy living environment.

As of 2020, the sustainability strategy consists of twenty-one documents developed by the municipality. They operate in correlation with regional, national and international strategies. The process of creating documents that make up the strategy is noteworthy, it is continuous rather than closed. This can be seen in the naming, where in addition to strategies, there are also outlines and approaches. The latter are usually acts initiating work on more detailed documents. Grading the policy-making process in a given field allows for both greater coherence and needed alterations of the general strategy.

The municipality’s efforts to showcase individual elements of the strategy are worth mentioning. The documents are characterized by high accessibility, understandable language, and attractive graphic design. They all build up a vision of a healthy, safe and economically innovative city fueled by clean energy. As such prospect is an ambition of many cities, Rotterdam’s municipality stands out in terms of social participation, actively encouraging its citizens to contribute to the process of becoming sustainable. Many of them contain elements designed directly for residents, educational or inspiring action. Making residents conscious and active is part of the strategy itself. For this reason, accessible communication of its elements increases its coherence.