The Role of Urban Design in Creating Resilient Public Open Spaces Surrounding Urban Small Watercourses: A Case Study of the Kumodraz Stream in Belgrade

Abstract

Small urban watercourses, often neglected and underdeveloped, have the potential to become integrated parts of the network of urban open public spaces. In this process, urban design plays the key role in their functioning and resilience, strengthening their capacity as high-quality open spaces. The current principles and roles of urban design only partially meet the requirements in making these spaces resilient. This article questions the existing principles and roles of the current practice and proposes a different perspective on the urban design of open public spaces surrounding small urban watercourses, within a framework of socio-ecological resilience. The research consisted of two parts. In the first part, based on both the specific characteristics of the public open spaces surrounding small urban watercourses and discussions of their quality, framed by the concept of socio-ecological resilience, a set of attributes was developed that defined their quality. In the second part, this set was tested through a case study of the Kumodraz stream in Belgrade, Serbia and translated into responsive urban design guidelines in a specific context. This was supported by a pilot survey of 346 potential users of the location. The findings of the case study show that urban design occupies a redefined and very specific position in the revitalization process of open public spaces surrounding small urban watercourses. In addition to its fundamental role in increasing the capacity of spaces and creating high-quality open spaces, it also helps to establish an integrated approach to the revitalization of the spaces surrounding small urban watercourses in a local context.

1. Introduction

Public open spaces surrounding small urban watercourses belong to a unique type of public open spaces because of their specific characteristics. Their uniqueness stems from the specific interchange between the water and the surrounding environment. The combination of nature and human activities makes them important in increasing the urban quality and appealing places in which people can spend their free time.

The regulation of small watercourses, which has dominated the last century, relies mainly on conventional solutions—concrete channels and culverted and buried rivers and streams. This has contributed to the loss of their role and importance, which has affected the ambient, functional and aesthetic qualities of urban spaces [1,2,3]. Often neglected and unkempt, many of them have been transformed into barriers between different parts of the city, neglected spaces [4] and spontaneous open green spaces [5]. However, they still have the potential to exert a positive effect in improving the quality of life of urban residents and regenerating parts of the city—and, in special cases, even the entire city—and can be considered a catalyst for the development of residential areas [6,7].

With their attractive design, open public spaces surrounding small urban watercourses serve as important gathering places for communities, by providing recreational opportunities and enhancing the quality of urban areas. However, these spaces also have a crucial role in helping cities to respond to climate change in a sustainable manner. Given their location in the urban environment, along with their characteristics, these spaces can positively contribute to cities’ efforts to address the challenges posed by climate change, by adapting to the disturbances that have resulted from these changes [1,2,8,9]. Climate change, which is rapidly accelerating and becoming more intense [10], is now considered a key factor shaping the future and poses a significant challenge to sustainable development and the achievement of the Agenda 2030 goals [11]. Climate change awareness is now at the center of the sustainability debate and is creating interest in new directions of development within the sustainability framework [12].

The uncertainty surrounding the development of cities due to climate change has led to a shift in thinking towards a new approach. The objectives and approach have changed the ways in which the natural disturbances affecting cities are considered, as well as the ways in which cities cope with them. The goal is no longer to restore the affected system and return it to its previous state. Instead, it focuses on strengthening the system and enabling it to cope with any subsequent change or possible threat [13,14]. Drawing strength from knowledge and past experiences, the system uses both external and internal changes to become better prepared for future disturbances [13]. Such an approach is based on the concept of socio-ecological resilience [13,14,15,16,17,18], which establishes part of the theoretical foundation of this article.

When a socio-ecological system is resilient, this does not necessarily mean that it has a positive effect on other systems within the same space, nor does it mean that the entire space can be considered resilient [14,19,20]. For example, some highly resilient configurations can negatively impact people’s quality of life [14]. Similarly, focusing on strengthening only ecological resilience by promoting biodiversity and green space connectivity in a specific area does not necessarily enhance the resilience of the community and infrastructure simultaneously [20]. A space can be resilient in some aspects but may lack other qualities of open public spaces, and, as such, may not enhance the overall quality of life [14,20]. This represents the main challenges of resilience: how to harmonize the resilience of different systems in one space [14,20] and how to guide trajectories towards positive outcomes [13,21]. The quality of open public spaces is considered a universal value that must be attained and operates within the framework of sustainability [22]. Enhancing resilience is the best means to increase sustainability in an uncertain and insecure future [13,18,23].

The role of open public spaces surrounding small urban watercourses and their potential are recognized as important in responding to the consequences of climate change by enhancing their resilience [1,2,8,9,24,25,26]. This can be achieved by improving the quality of these areas, as well as by strengthening their capacities to create attractive, safe and accessible spaces for citizens, throughout the year. Urban design plays the key role in this process, and its principles must be redefined according to the principles of socio-ecological resilience in order to address the ongoing challenges effectively.

The empirical part of this research is conducted in Belgrade, Serbia and focuses on small urban watercourses. Small watercourses, as per the Serbian classification based on their watershed areas, include streams with watershed areas smaller than 100 km² and small rivers with watershed areas between 100 km² and 1000 km² [27]. In Belgrade, the open public spaces surrounding small urban watercourses are currently inaccessible, unmaintained and unsafe, creating barriers in the city environment [28,29]. Despite the clear strategy of creating green–blue corridors, along with the understanding of the need for an integrated and holistic approach to flood risk management that significantly emphasizes both ecological and social value [24,25,27], there are still numerous practical solutions in places where small watercourses are regulated in concrete channels and culverted. Studies and research addressing the revitalization of small urban watercourses within the scope of urban planning and design are scarce, not only in Belgrade but also across Serbia [9,25,28,30]. It has been observed that urban design is often overlooked in studies focusing on the revitalization of the areas surrounding small urban watercourses. In response to such a gap, this research is undertaken to underscore and advance the significance of urban design in this revitalization process and highlight its role in shaping open public spaces that align with the principles of socio-ecological resilience. Moreover, it aims to position urban design as part of an integral approach, together with related fields of research that share a concern for the same issues within a local context. The empirical segment of the research is conducted on the example of the Kumodraz stream in Belgrade.

Therefore, the aim of this research is twofold: (1) to identify ways to enhance the space capacities within the scope of urban design and (2) to define the position and significance of urban design in the revitalization of open public spaces surrounding small urban watercourses, supporting both resilience and the creation of high-quality open public spaces. This research calls for the redefinition of the principles on which the urban design of open public spaces rests, suggesting that it should be based on the principles of resilience within the context of small urban watercourses. By defining this new approach and establishing guidelines for urban design, it aims to enhance the capacity of spaces to create high-quality resilient areas and support their revitalization in an integrative and resilient way. The findings presented in the Discussion section show how change can be achieved and how urban design can play the key role in revitalizing the open public spaces around small urban watercourses, offering valuable insights for local planning authorities.

2. Research Framework

2.1. Characteristics of Open Public Spaces in Areas Surrounding Small Urban Watercourses

In the context of socio-ecological resilience, the open public spaces surrounding small urban watercourses can be considered specific socio-ecological resilient systems. Many studies investigating how cities function under conditions of uncertainty have identified cities with this type of system [13,15,31].

The fundamental principles of socio-ecological resilience are based on the characteristics of socio-ecological systems, their dynamics and their self-organization [13,18,31]. They represent a type of complex adaptive system and they have been created in response to an unpredictable future [32]. When faced with disturbances and changes, these systems reconfigure themselves, creating a more robust system with the ability to adapt and respond to change more effectively [13,18]. Raising the capacity to improve resilience increases the likelihood that the desired trajectories will develop when faced with an uncertain future, in areas where disruptions are frequent [13].

The term “socio-ecological” is used to emphasize the integral connection between man and nature and to show that the separation of the natural from the social system is an unnatural and artificial creation [13,31]. In this context, the term “social” is taken broadly and represents a wider framework, encompassing the economic, social and cultural characteristics of the system [31,33].

When looking at the areas surrounding small urban watercourses, it has been noted that the characteristics of such socio-ecological systems are more visible and prominent than in many other open public spaces. This is mainly due to the abundant natural features present here, such as water and a variety of green spaces. They represent a specific type of open public space that creates a variety of interchanges between water bodies—streams and retention basins, their banks and floodplains, and greenery [7,9]. Because of the nature, diversity and wealth of natural elements present here, these spaces have the potential to become resilient in their own right. What is considered the key relevant factor in the planning and design of these spaces, along with their integration into the urban fabric, is the understanding of the ecological value that is present here and how the existing natural processes function, both separately and in connection with each other, as well as the dynamics that their existence brings [34].

In many cities, the open spaces surrounding small urban watercourses are still in an underdeveloped and unkempt state. According to the typology developed by Matthew Carmona [3], three categories of unorganized spaces that do not fulfil their potential, and need to be restored and recovered, are identified: (1) neglected spaces, in terms of their physical characteristics or vis a vis market forces; (2) isolated spaces where physical and psychological barriers are present; and (3) homogenized spaces that do not stand out in any way and do not fit into the environment [4]. Michael Hough recognizes a group of forgotten urban spaces, overgrown with unkempt greenery, that are often flooded and characterized by low-quality ecosystems. He believes that such spaces, which are common in cities, have much greater potential for the introduction of nature into cities after their rehabilitation and recovery from formally arranged green park areas [5].

Spaces that can support more than one function and combine their uses in accordance with the needs and aspirations of society have great potential if properly managed [34,35]. In order to realize their full potential, the open public spaces surrounding small watercourses must be of high quality and successful in meeting the ecological, social, aesthetic and economic requirements, as well as being developed in accordance with the climate change mitigation and adaptation principles, measures and standards. The role of the multifunctionality provided by ecosystem services is important, but the multifunctionality brought by an adequately designed space that organizes activities temporally and spatially, and, at the same time, serves as a training ground in responding to the consequences of climate change—especially floods and warming—should also not be neglected. For example, if a flood occurs, open public spaces, combined with green infrastructure, are important in spreading water and collecting it [36]. Green infrastructure refers to a carefully planned network of natural areas, as well as their environmental features, designed and managed to provide various ecosystem services. It includes green spaces or blue spaces (for aquatic ecosystems) [37]. Green infrastructure, as an integral part of open public spaces, makes a great contribution in terms of increasing the diversity of ecosystem services, reduces the flow speed, reduces erosion, enables purification and contributes in social and aesthetic terms [25,38,39,40]. In addition to fulfilling the role of being climate-responsive and protecting the population from the effects of climate change, along with improving ecosystems, these spaces must also play a role in the lives of citizens—they must be designed to be part of the everyday life of a city. To achieve this function, they must be designed as high-quality open public spaces to give vitality to city life.

The open public spaces that surround small city watercourses must be viewed integrally with the environment, because, due to their dimensions and characteristics, they represent, both visually and functionally, an inseparable whole. They are determined by the spatial context within which they exist and must be designed following all of the specifics of these spaces. As such, they present great potential to become the key drivers resilience, capable of providing sensitive responses to disturbances, preserving the functionality and quality of urban systems and constantly adapting, transforming and re-adapting to new conditions. As such, they serve the citizens—allowing them to live in a healthy, safe and attractive local environment.

2.2. Quality of Public Open Spaces Surrounding Urban Small Watercourses to Support Resilience

Understanding what constitutes the quality of open public spaces and the factors contributing to it is a widely studied issue in urban design [41,42,43,44,45,46,47,48,49,50], and the resilience of a space is recognized as one of the most important factors that influences its quality [50,51]. This is particularly important for open public spaces near small watercourses. Open public spaces, as socio-ecological systems [13,15,31], enhance their resilience by building their capacities, thereby improving and increasing their quality [13]. Each open space possesses distinct quality attributes that contribute to its unique identity and characteristics [48]. Capacity building improves all aspects of quality, which is essential in creating quality spaces that support resilience.

Understanding the quality of an open space often depends on the perspective from which it is viewed. There is an angle or a layer of observation that is important: this may be perceptual, visual, morphological, temporal, social or functional, i.e., the relationship with the dominant activities or physical aspects of the space [41]. Seen from the authors’ point of view, who consider natural processes as the most important prerequisite for urban design, the quality of an open public space depends on the vitality of the natural processes and ecosystem services that enable people to enjoy high quality of life [34]. The importance of nature is not neglected by other authors who focus on social processes in space. Jan Gehl states that the most attractive combinations for the creation of open public spaces arise when spaces are connected to greenery, interesting landscapes or water surfaces that create completely new patterns in the use of space [42]. Water and greenery have the properties of providing relaxation and recovery and are therefore among the most important elements of a modern open public space [41].

Urban designers often neglect the time factor when creating open public spaces, while the place where activities occur is considered the most important [28,30,31]. Both the time and the place in which activities will be performed need to be of equal importance for urban designers [52]. The activities that arise in a space must be coordinated in time. Understanding the patterns of activity in space and time, and the constant search for new patterns, makes it possible to achieve the synergy of the activities in one space and increases the quality of the space [41,43,52,53].

High-quality open public space is the right of every human being. A space with a greater humane dimension cares for people and enables connection within the community, indicating its potential to create a living city and improve its resilience [42]. Cities that enable visible urban life have the most numerous and high-quality open public spaces. The interactions that occur strengthen the community and help community members to organize and cooperate, which is especially important when faced with a problem or threat. Public open spaces are probably the best platforms for the connection of people [44]. A high-quality space stimulates openness and communication between people [42], and the space must be accessible, attractive to users and available to all groups of users equally [45].

The quality of open public spaces is a universal concept, but the criteria used to evaluate it must constantly be adjusted to the changes that society faces [41,52]. At present, the greatest emphasis is on climate uncertainty, but we should not neglect the impacts and changes that occur at the level of each city individually and at the levels of different local communities.

3. Materials and Methods

This research consisted of two main parts: theoretical and empirical. The purpose of the theoretical part, whose framework was presented in the previous section, was to produce a set of attributes that determine the quality of open public spaces along small urban watercourses. These attributes were then used in the empirical part of the research.

The empirical part involved a case study of the Kumodraz stream in Belgrade, Serbia. In this case study, the derived set of attributes was applied to the specific context. The methods used in the case study included a survey, a review of the existing research and planning documents and fieldwork. The results were then translated into urban design guidelines tailored to the specific context (Figure 1). The details regarding the research methodology are outlined and presented in the sections below.

3.1. Theoretical Part

The theoretical part of the research focused on the specific characteristics of the public open spaces surrounding small urban watercourses and examined their quality through the lens of socio-ecological resilience. A literature review on the quality of open public spaces in the specific context of small urban watercourses identified various factors influencing the quality of such spaces, including the natural characteristics, social interactions, the spatial and temporal arrangement of activities, socio-ecological resilience, etc. These factors were consolidated into a set of attributes that either influence or determine the quality of the public open spaces around small urban watercourses.

The quality of these spaces was evaluated based on four categories, each containing specific quality attributes: (1) comfort and character, (2) accessibility and connectivity, (3) activities and use and (4) social qualities. The categories were based on the Project for Public Spaces (PPS) classification [46]. This set of attributes, presented in

Table 1. The attributes of the quality of a space.

Comfort and Character	Connectivity, Integration and Accessibility
connection between water and banks protection of floodplains climate-responsible design diversity and visibility of green infrastructure presence of water-permeable surfaces biodiversity use of autochthonous species integration of flood control structures in an attractive way integration of natural heritage into the space integration of cultural heritage into the space adaptability transformability combination of natural and man-made elements spaces with unique character appropriate street furniture smart street furniture that supports digital technologies safety use of green infrastructure and water in a safe way use of local resources dynamics of space	connection to public city transport pedestrian connections cycle routes connection with other green areas within the city boundaries connection to other open public spaces along watercourses connection to other green infrastructure areas ecosystem networks sufficient parking spaces integration into the surrounding environment (built and natural) access to open public spaces access for users with special needs areas that allow water to be observed from above interconnection of places with pathways and water crossings integration of existing barriers into the space linkages of units with different character recognizability of public open spaces responsive to citizens’ cultural attitudes related to public spaces
Activities and Use	Social Qualities
interactivity diversity of functions and uses compatibility with surrounding uses variety of activities temporal compatibility of activities grouping of different activities in space representation of local activities various options for different groups of users (something for everyone) scheduling activities in relation to the dynamics of natural disturbances multifunctionality of flood and erosion control structures establishing a relationship between people and greenery through a variety of activities establishing a relationship between people and water through a variety of activities support for exploration and discovery	space for all social groups designated areas for children, the elderly and people with special needs areas for pets liveliness of space existence of many optional activities multiculturalism community self-organization variety of social interactions—encouragement of openness and communication space that supports education raising awareness about the protection of nature raising awareness of the importance of maintaining nature-based systems raising awareness about potential disturbances (e.g., flash floods) raising social capacity for learning providing areas for people to socialize

, was then used and validated in the empirical part of the research.

The set of space quality attributes was not intended to form a model for the quantification of resilience criteria; rather, it reflected the qualitative aspects of a space. It served to highlight the key factors of space quality in the context of socio-ecological resilience and to identify systems whose capacities need to be enhanced when developing resilient and high-quality public open spaces surrounding small watercourses. Therefore, urban design is recognized as the key tool in improving the quality of public open spaces and should be used to enhance selected attributes to increase their resilience. The selection of attributes depends on the local context, i.e., the characteristics of the public open spaces, as well as the attitudes and opinions of respondents about the potential future appearance of the open public spaces surrounding small urban watercourses.

3.2. Empirical Part

The second part of the research—the empirical part—was conducted within a defined theoretical framework [36]. Its goal was to test and potentially verify a predetermined set of attributes in a specific context. An additional objective was to use the results as input for the development of guidelines that could be further used to improve the resilience quality of a space. The practical research was conducted as a case study of the Kumodraz stream in Belgrade.

The case study method was chosen for several reasons. First, it is appropriate for the verification of an established set of attributes, based on an extensive theoretical framework, in a specific context. Second, this research did not clearly distinguish between a phenomenon and context, which is characteristic of case studies [54,55]. In addition, this method tends to yield descriptive results [55]. Finally, it can encompass other methods within itself. In this research, the following methods and techniques were used: a critical review of the literature, content analysis, observations of the objective reality and the survey technique, which presents subjective views on the objective reality and the future state.

The pilot survey used in this research served two main purposes: (1) to obtain the data, which would otherwise have been difficult to collect using other methods, and (2) to involve local residents in the urban design process. It had a limited scope and therefore could be seen as a supplementary tool and an illustrative example of the importance of the participation of citizens in the planning and design of these spaces.

The survey aimed to determine to what extent the respondents (the potential users of the open public spaces) were familiar with the current state of the streams and their expectations with regard to them.

The pilot survey was structured into two parts. The first part assessed the citizens’ knowledge about the streams, their current state and the issues that they faced. This section consisted of multiple-choice, close-ended questions where the respondents could choose up to 5 out of 11 provided answers. The questions were based on both fieldwork and a review of the current research and planning documents, and they were eventually used to identify the key issues that the streams were faced with (presented in Section 5.1).

The second part of the survey focused on the respondents’ vision and how they wished to use the spaces along the streams (presented in Section 5.2). The respondents answered two multiple-choice, closed-ended questions (choosing up to 5 out of 10 options and up to 6 out of 12 options) and one single-choice question that included photographs. The questions were formed based on the knowledge obtained from the research framework. The future users’ needs largely determine the activities that will be performed in public open spaces and their appearances. The questions and options were categorized as per the needs identified by Carr et al.: (a) comfort, (b) relaxation, (c) passive involvement, (d) active involvement and (e) discovery [47].

The pilot survey was carried out online in February 2024. Since it was used as a supplementary tool to verify a set of attributes and support the research methodology, and was not intended for perfect generalization, we distributed it via email and social media groups frequented by Belgrade residents interested in urban development issues. This approach allowed us to avoid complex participant recruitment. By targeting Belgrade citizens interested in urban development and the preservation of public spaces, we were able to achieve higher completion rates for the survey. The survey was anonymous, and the participants were informed about its purpose and given the choice to participate. It was indicated at the beginning that only adult residents of Belgrade should complete it. The initial number of respondents was 355, with nine eliminated due to incomplete information or an incorrect place of residence, which consequently resulted in 346 valid responses.

The main goal of the survey data analysis was to identify the respondents’ attitudes regarding the current state of the streams and their desired future appearance. The analysis was conducted using statistical methods and processed using the SPSS statistical software (IBM SPSS Statistics 27). Applying the SPSS frequencies method to the overall sample revealed the most significant problems associated with small watercourses, the preferred appearance of streams and the desired activities along streams, as well as the preferred design of the pathways alongside the streams.

However, it was crucial to identify the preferences not only of the overall survey sample but also of specific groups, in order to ensure that the spaces would be designed for all and could accommodate diverse lifestyles, offering activities and spatial units for everyone [49]. Therefore, the respondents were categorized by age into six groups to ensure the presence of all age groups and by the part of the city that they lived in, i.e., those who lived near the Kumodraz stream (47.9%) and those who lived farther away (52.1%), since the temporal dynamics of space usage, i.e., organizing activities over time [41,52,53], will differ between these two groups. To achieve these objectives, the cross-tabulation method was utilized to determine whether there were statistically significant correlations between the respondents’ age groups, their places of residence and their individual responses to the three multi-choice and one single-choice questions. A significance level of 0.05 was applied. The results were then used to (a) define specific aspects of the quality of the space in order to identify attributes whose capacities should be strengthened and (b) provide input for the urban design guidelines.

The limitations of the sample and the survey were as follows. (a) The survey was conducted online, restricting participation to individuals with internet access. This can be considered a partial limitation, although, according to the Republic of Serbia’s Institute of Statistics, 95.7% of citizens own a mobile phone and 85.4% of citizens use the internet [56]. (b) The survey only included adult citizens, excluding the opinions of those under 18 years old. (c) The number of respondents was small relative to the total population of Belgrade, but it was suitable for a pilot survey. The sample did not necessarily reflect the opinions of all Belgrade residents due to the specific nature of the survey and its targeted distribution. (d) The sample included all age categories, which were approximately equally represented, although it was noted that the majority of the participants fell within the 35–44 age group (29.9%), while the 65+ age group constituted the smallest percentage of respondents (8.9%).

The research results are presented in two sections: Section 5.1 and Section 5.2.

Section 5.1 defines the characteristics of the public open spaces surrounding the selected small watercourse—the Kumodraz stream. The data on the stream’s current state were obtained by studying relevant planning documents, reviewing the literature related to the Kumodraz stream, observing the site and analyzing the results of the first part of the residents’ survey, related to the most significant problems. These data were then organized through a SWOT analysis, a standard analytical method in urban design [57].

Section 5.2 presents the pilot survey results pertaining to the area’s appearance, environment and the activities that the respondents wished to see around the stream. This section provides input for the next step, defining the aspects of the quality of the space in the local context.

Finally, the Discussion section connects the results obtained in Section 5.1 (SWOT analysis) and Section 5.2 (aspects of space quality in the local context) using analytical methods from urban design [47,58]. This connection forms the basis for the selection of appropriate features in the local context, ultimately resulting in urban design guidelines focused on enhancing the capacities presented in the specific context.

The following sections will present the results of the practical research methodology and the main findings from the survey translated into urban design guidelines, as well as the conclusions on the role of urban design in creating resilient public open spaces surrounding small urban watercourses.

4. Study Site—Kumodraz Stream, Belgrade, Serbia

The Kumodraz stream is one of 187 small urban watercourses in Belgrade [25]. The upper part has remained unregulated and open. The lower section of the flow is culverted in accordance with conventional stream regulation practices [29]. Throughout its entire course, the Kumodraz stream serves as a recipient of untreated wastewater, rainwater, landfill and agricultural runoff. It has also been noted that the stream carries pollutants from the surrounding catchment area [28].

The catchment area of the Kumodraz stream is approximately 8 km². The wider area through which the Kumodraz stream flows consists of hilly terrain with formed valleys [59]. The upper section of the stream, which is less urbanized, is often surrounded by green open spaces. The valley of the Kumodraz stream is rich in vegetation and wet habitats [60].

The research was carried out in the upper and middle sections of the Kumodraz stream, flowing on the surface and unregulated. The open public spaces are surrounded mainly by residential areas. The map indicates the specific area where the research was conducted in relation to the city center (Figure 2). The current state of the stream is shown in Figure 3.

5. Results

5.1. Characteristics of Public Open Spaces Surrounding Kumodraz Stream

This section will present the results of the first part of the survey and SWOT analyses.

Firstly, the respondents were asked about the most important problems facing urban small watercourses. They were given eleven options to choose from and could select a maximum of five. The survey results showed that the majority of the respondents considered ecological problems related to river pollution to be the most important. Specifically, untreated wastewater discharge into streams (85.3%) and the littering of streams and surrounding areas (77.2%) were cited as major concerns. Social and aesthetic issues were also highlighted as significant, with the citizens expressing concerns over illegal construction along the banks and the presence of informal settlements (

Table 2. Percentage frequency distribution of respondents’ opinions about the most important problems facing urban small watercourses (total of 346 respondents).

Problem	Frequency	Percentage
Littering of streams and surrounding areas	267	77.2
Untreated wastewater discharge into streams	295	85.3
Inaccessibility of streams	107	30.9
Flooding	25	7.2
Underutilization of areas that can be used for socialization and recreation	166	48
Unappealing look	120	34.7
Illegal construction along the banks	118	34.1
Unsanitary informal settlements surrounding waterways	146	42.2
Lack of fish and other wildlife due to pollution	98	28.3
Areas feel unsafe due to poor access and/or lack of maintenance	60	17.3
Degraded ecosystem	111	32.1

).

Using the cross-tabulation method and analyzing the contingency table, the chi-square statistic indicated a significant correlation between the age of the respondents and the issue of illegal construction along the banks, χ² (5) = 12.683, p < 0.05. The percentages shown in the table indicate that respondents aged 35–44 and 45–54 years considered this problem less significant, while those aged 25–34 and over 65 years viewed it as more significant. Another statistically significant association was found between the age of the respondents and the issue of the inaccessibility of the streams, χ² (5) = 16.400, p < 0.01. Older respondents regarded this as a problem, while younger respondents considered it less significant (

Table 3. Cross-tabulation showing the relationship between the age of the respondents and (1) illegal construction along the banks and (2) the inaccessibility of streams.

	Illegal Construction along the Banks (%)		Inaccessibility of Streams (%)
Age	No	Yes	No	Yes
18–24	22.9	20.3	25.2	15
25–34	17.6	28.8	22.3	19.6
35–44	30.8	28	30.7	28.0
45–54	11.5	7.6	9.2	12.1
55–64	10.1	3.4	7.6	8.4
65+	7	11.9	5	16.8

). Interestingly, the survey also revealed that the citizens perceived floods as the least significant problem (7.2%), despite relatively recent incidents that caused significant material damage and even human casualties [28]. Other cross-tabulations related to the correlation of the respondents’ gender, place of residence and age with the problems with small watercourses found no statistically significant chi-square statistics in most cases. Men, women and residents living both near and farther from the streams viewed the problems of small watercourses similarly.

Table 4. Characteristics of public open spaces presented through strengths, opportunities, weaknesses and threats.

Strengths	Weaknesses
Preserved surface flow Lots of greenery Location relating to downtown area Location relating to nearby residential areas Preserved floodplains	Existing landslides Unregulated settlements nearby Can dry out Inaccessibility of streams Littering of surrounding areas and water Filled in in some places
Opportunities	Threats
Undeveloped areas adjacent to the stream Can be integrated into the blue–green network Preserved surface flow Preserved riparian areas Existing open public areas in the upper segment of the stream can be used for socialization and recreation Presence of wetlands	Pollution and sewage discharge Illegal settlements on the streambanks Illegal landfill adjacent to the stream Prone to flooding in the area where it enters a sewage system Prone to flooding Can dry out

presents the SWOT analysis. This analysis summarizes the characteristics of the public open spaces surrounding the Kumodraz stream. The data for the SWOT analysis were collected through observations of the current state of the areas surrounding the small urban watercourse, a review of the existing research on the Kumodraz stream, planning documentation and the survey respondents’ opinions on the problems facing these streams.

5.2. Respondents’ Attitudes Regarding Future Appearance of Stream

This section will present the results from the second part of the survey. The results indicate the respondents’ views on the desired appearance and activities of small watercourses.

The pilot survey was used to determine whether the preferences of all groups of users, categorized by age and place of residence, were aligned with the views of the entire sample. This was crucial in ensuring that the provision of spaces and activities would cater to all types of users. The first question inquired about the future state of the streams, offering the respondents a choice of ten spatial units with different appearances and characteristics (

Table 5. Percentage frequency distribution of the preferred development options for the Belgrade streams (total of 346 respondents).

Spatial Units with Different Appearances and Characteristics	Frequency	Percentage
Historical parks	98	28.3
Natural park with educational elements	188	54.3
Art in open space	63	18.2
Walkways along streams	313	90.5
Park rich in nature and wildlife	229	66.2
Areas for relaxation and observation of local flora and fauna	186	53.8
Spaces for interaction with water	180	52
Spaces for socialization and relaxation	92	26.6
Gathering places and areas for public performances	46	13.3
Restaurants and cafes	33	9.5

). The results revealed that the majority of the respondents favored walkways along the stream (90.5%), followed by a park rich in nature and wildlife (66.2%) and a natural park with educational elements (54.3%). Conversely, the respondents showed the least interest in places like cafes or similar (9.5%).

Using the cross-tabulation method and analyzing the contingency table, the chi-square statistic indicated a significant correlation between the age of the respondents and their preferences for different types of spaces—specifically spaces with cafes, χ² (5) = 11.907, p < 0.05. It was observed that the overall sample differed from the specific groups’ responses. Although the smallest number of respondents expressed a desire for cafes in the open spaces surrounding the small urban watercourses relative to the total number, the largest percentage of young people aged 18–24 (45.5%) considered them desirable (

Table 6. Cross-tabulation showing the relationship between the age of the respondents and spaces with cafes and restaurants.

	Restaurants and Cafes (%)
Age	No	Yes
18–24	19.6	45.5
25–34	22.1	15.2
35–44	31.7	18.2
45–54	10.3	9.1
55–64	8	6.1
65+	9	6.1

).

The first question in this part of the survey focused on comfort, relaxation and passive forms of engagement in the space (33), while the second question considered more active forms of entertainment. The respondents could choose multiple activities from the twelve provided, with a maximum of six selections. The survey results indicated that the respondents overwhelmingly preferred walking (91.9%) and cycling and rollerblading (65.9%) as activities. Conversely, they least preferred skate parks (5.8%) and mini golf (6.1%). It was determined that the most desirable activities should be integrated throughout all open spaces along the stream, while the less preferred activities should be incorporated into specialized areas, as indicated in

Table 7. Percentage frequency distribution of the chosen activities (total 346 respondents).

Activity	Frequency	Percentage
Fishing	90	26
Swimming and playing in the water	95	27.5
Walking and hiking	318	91.9
Dog walking	144	41.6
Cycling and rollerblading	228	65.9
Mini golf	21	6.1
Skate parks	20	5.8
Kayaking and canoeing	113	32.7
Ice skating trails	59	17.1
Playgrounds	150	43.4
Plein air painting and outdoor art	88	25.4
Sports fields	89	25.7

.

After analyzing the contingency tables, the chi-square statistic was found to be statistically significant, indicating a relationship between the distance between the respondent’s place of residence and the location and children’s playgrounds, χ² (1) = 10.598, p < 0.01 (analyzed by SPSS cross-tabulation). Respondents who lived closer to the stream preferred this activity (58% of them) significantly more compared to those who lived farther away.

The third question presented three different types of walking paths along the stream for citizens to choose from (Figure 4). The majority of the respondents preferred a boardwalk, an elevated pathway above the ground and water and water in a natural setting within a city park (46.6%). This was followed by a naturally designed path near a naturally landscaped stream in an environment that resembled untouched nature (40.8%). The least favored option for the respondents was a concrete promenade (12.5%). After analyzing the contingency tables, no statistically significant chi-square statistic was found for the place of residence, age or gender in relation to this question.

6. Discussion and Conclusions

6.1. Survey Findings—Aspects of Quality of Space

The pilot survey results indicated that nature is the most important factor in the creation of open public spaces surrounding small urban watercourses. The responses emphasized the importance of nature in the city, the protection and removal of pollution and the prevalence of informal landscapes. Contact with water and green elements, along with plant and animal life, promoting relaxation and unwinding, is considered noteworthy. The pilot survey results also highlighted the significance of the social aspect of a space, in terms of socializing and gathering, as well as the educational aspect in the context of climate change and nature conservation. This summary highlights the key findings of the pilot survey that influence the aspects of quality of open public spaces in the specific context of the Kumodraz stream. These aspects determined the selection of attributes regarding the quality of the space along the Kumodraz stream, from the set of attributes derived from the research framework presented in Table 1.

The pilot survey results from specific groups of respondents are equally as important as those of the overall sample in designing public open spaces surrounding small urban watercourses. The findings are as follows: (1) users aged 65 and above emphasize the importance of accessibility, which differs from the total number of respondents; (2) residents living near the Kumodraz stream believe that having children’s playgrounds in the area is desirable; (3) while all respondents indicate that open spaces with cafes and restaurants are less desirable (9.5%), it is important to note that, among the 18–24 age group, 45.5% find them attractive. These findings were integrated into the urban design guidelines, along with the overall results.

According to the pilot survey results, most users chose the following answers: (a) spatial units with different appearances and characteristics—walkways along the stream (90.5%), parks rich in nature and wildlife (66.2%), educational elements in natural parks (54.3%), areas for relaxation and the observation of local flora and fauna (53.8%), spaces for interaction with water (52%); and (b) activities—walking and hiking (91.9%), cycling and rollerblading (65.9%), playgrounds (43.4%), dog walking (41.6%). These units and activities should be integrated longitudinally along the entire flow as connecting elements. Less popular activities, such as kayaking and canoeing (32.7%), outdoor art and plein air painting (25.4%), sports fields (25.7%), ice skating trails (17.1%), fishing (26%), swimming and playing in the water (27.5%), historical parks (28.3%) and areas for socialization and relaxation (26.6%), should also be included in public open spaces to offer a variety of activities, as points of interest in these areas. Additionally, activities favored by a small number of users, like mini-golf or skate parks, should also be considered in specific open spaces to cater to smaller groups of users.

The pilot survey findings are used as input data for the findings and conclusions presented in the next section. The purpose of the pilot survey findings in this research was to select the relevant attributes related to the quality of the space, chosen according to the context, as well as to support the urban design guidelines.

6.2. Urban Design Guidelines and Capacity Improvement Measures

An analytical approach to urban design that connects (1) the set of attributes derived from the theoretical framework, (2) the data obtained from the analysis of the site, along with corresponding planning documents, (3) the results of a survey on the citizens’ attitudes towards the current situation at the site, possible changes and the future appearance of the restored streams, and (4) the attributes applicable in the context of the location of the Kumodraz stream, was used to propose guidelines for urban design (

Table 8. The quality attributes of the open public spaces surrounding the Kumodraz stream—comfort and character.

Comfort and Character
Space Quality Attribute	Capacity Improvement Measures and Guidelines for Urban Design
Connections between water and banks	Riparian areas are especially important. Create a clear boundary of retention, using rocks in some areas and natural vegetation in others. This area should be attractive and rich in diverse plants. Designate places for interaction with water in a safe way. Overall, 52% of respondents highlighted spaces for interaction with water.
Climate-responsible design	Use nature-based systems, increase the amount of greenery, provide various sunshade structures, use trees and shrubs as windbreaks, utilize flood control structures in a multifunctional way and manage water levels and flood waves with designated flood zones and retention areas.
Diversity and visibility of green infrastructure	Utilizing natural materials and vegetation and nature-based systems can greatly contribute to the collection and treatment of stormwater and wastewater. Integrate a wide range of systems and make them visible and accessible for educational purposes. Overall, 54.3% of respondents highlighted natural parks with educational elements.
Protection of floodplains	Preserve the undeveloped space surrounding the Kumodraz stream in order to enable future expansion and adaptation to climate change. Preserved floodplains are recognized as a strength.
Integration of flood control structures in attractive ways	With natural channel design, it is very important to integrate nature-based systems in a visually appealing way. They should be positioned to be accessible, with retention as the central element, allowing safe access, and with plant selections that enhance the quality of the space. Detention basins should be integrated as attractive spaces that can be used daily—for example, as playgrounds, mini-golf areas or parks.
Presence of water-permeable surfaces	Potentially, the entire area can be preserved as a permeable surface, with natural paths and walkways. Overall, 46.6% of respondents preferred elevated paths, while 40.8% preferred naturally designed paths.
Adaptability	Use nature-based living systems that can adapt to varying amounts of precipitation. Utilize multifunctional flood control structures.
Transformability	Using aquatic systems for water treatment can improve the water quality, allowing for activities like swimming and fishing, while also restoring animal and plant life. Overall, 27.5% of respondents chose swimming and playing in the water as a desirable activity, and 26% preferred fishing.
Biodiversity	It is important to enhance existing ecosystems and introduce compatible species. Consider selecting plants that will attract birds or butterflies. Overall, 53.8% of the respondents highlighted areas for relaxation and the observation of flora and fauna.
Use of green infrastructure and water in a safe way	When designing retention areas, safety is crucial. In wet habitats, it is important to plant dense vegetation to prevent public access to unsafe areas. Design access to nature-based systems with safety in mind. Designate areas adjacent to retention areas where it is safe to interact with the water. Ensure that access points and paths are fenced. Place markers to indicate where the floodplain begins.
Dynamics of space	Design diverse open public spaces along the watercourse. Enhance the dynamism of the water flow. Create places where the water cascades, producing sounds while flowing over rocks, etc. Introduce wetland expansions along the watercourse to slow down the stream [61].

,

Table 9. The quality attributes of the open public spaces surrounding the Kumodraz stream—connectivity, integration and accessibility.

Connectivity, Integration and Accessibility
Space Quality Attribute	Capacity Improvement Measures and Guidelines for Urban Design
Connection to other open public spaces along the watercourse	Different areas along the watercourse should be designed holistically, connecting ecosystems and ensuring a cohesive form, visual appeal and functionality.
Connection with other green areas within the city boundaries	Establish pedestrian and bicycle paths that link with surrounding urban forests and green corridors in the wider area.
Pedestrian connections	When asked about their preferred activities along restored streams, 91.9% of respondents chose walking. Pedestrian paths should extend along the entire open public space, especially along the watercourse, with easy connections to the surrounding areas and nearby green spaces.
Cycle routes	Two-thirds of the respondents (65.9%) believed that it is essential to have bicycle and rollerblading paths. These paths, together with pedestrian routes along the stream, will link the riverbanks to other parts of the city.
Responsiveness to citizens’ cultural attitudes relating to public spaces	Based on the photographs provided in the survey, citizens prefer a more natural look. Therefore, landscaping should prioritize native species and avoid overly formal designs to encourage the return of nature through urban green corridors.
Interconnection of places with pathways and water crossings	Special attention should be given to intersections between bike routes and pedestrian paths or where paths from residential areas connect with open public spaces. These intersections should be carefully designed and equipped with appropriate street furniture. Places where they intersect with the stream offer numerous opportunities to design different types of crossings using natural materials.
Areas that allow water to be observed from above	Elevated walkways and various crossings allow water to be observed from above, providing an attractive solution. The elevated boardwalk option was selected by 46.6% of respondents.
Integration of existing barriers into the space	In the underdeveloped areas surrounding the stream, logs, old walls and infrastructure remains are often found. It is necessary to remove all barriers and creatively integrate these elements into the space wherever possible, revitalizing them with local art.
Accessibility for users with special needs	Ensure that all pedestrian paths are accessible to people with disabilities. According to the survey results, individuals aged 65 and above considered it crucial to improve accessibility. Provide accessible crossings over the water, considering slopes, widths and potential obstacles, such as steps.

,

Table 10. The quality attributes of the open public spaces surrounding the Kumodraz stream—activities and uses.

Activities and Uses
Space Quality Attribute	Capacity Improvement Measures and Guidelines for Urban Design
Compatibility with surrounding uses	The area is bordered by multiple residential neighborhoods, some of which are informal settlements with plans for future regulation. The green corridor of the Kumodraz stream is seen as a potentially significant recreational center for the neighborhood.
Various options for different groups of users—something for everyone	Various activities can be grouped into different areas, each with a primary function and a range of supporting activities.
Temporal compatibility	One way to utilize the same space differently in summer and winter is by converting walkways into ice skating paths during winter. Overall, 17.1% of respondents expressed a desire for skating paths along the stream. This transforms the character of the space entirely between summer and winter. Likewise, detention basins that are filled with water during high-water periods can be used for different activities during low-water periods.
Grouping activities in space	Some activities occur along the entire length of the stream, while others are confined to specific open public spaces along the stream. Combine complementary activities within dedicated spaces with a unique character, emphasizing one or two dominant activities along with several supporting ones.
Support exploration and discovery	Provide discovery kit rentals (binoculars, maps, etc.) for both children and adults and ensure access to nature.
Establishing a relationship between people and water though a variety of activities	Encourage users to make direct contact with the water, allowing activities on the water, such as swimming or fishing, as well as opportunities to observe and learn about water elements. Overall, 27.5% of respondents highlighted swimming and playing in the water, and 26% highlighted fishing.
Interactivity	Provide safe access to water and/or through water where feasible and enable users to interact with their surroundings.

and

Table 11. The quality attributes of the open public spaces surrounding the Kumodraz stream—social quality.

Social Quality
Space Quality Attribute	Capacity Improvement Measures and Guidelines for Urban Design
Spaces that support education	According to the survey results, 54.3% of the respondents chose natural parks with educational aspects. To create a park with educational content, it is important to incorporate informational boards that form an engaging narrative and reflect the different zones within the space. These boards should aim to educate citizens about the importance of preserving nature and maintaining nature-based systems, the role of native species and biodiversity and ways to respond to flash floods. Additionally, it is essential to include educational boards designed specifically for children, using materials that are easily understandable among them.
Designated areas for the elderly, children and people with special needs	Respondents living closer to the stream preferred children’s playgrounds (58%). Along the walkways, more space should be dedicated to children’s playgrounds, composed of natural materials, with the possibility of incorporating water features to enhance their appeal. The areas should also be designed and equipped to meet the needs of specific users—for example, with sensory considerations—ensuring that they are accessible to people with disabilities.
Areas for people to socialize	Create spaces that encourage socializing and interaction between users along the stream and in the retention area. Overall, 48% of respondents found the lack of socializing and recreation options in these areas important. Although the total sample considered cafes and restaurants undesirable, the 18–24 age group found them attractive.
Areas for pets	Designate specific areas for pets. Overall, 41.6% of respondents preferred dog walking as an activity.

). The urban design guidelines have been developed by utilizing knowledge and information obtained from analyzing the existing research, fieldwork and pilot survey results. These guidelines aim to enhance the resilience and quality of the open public spaces surrounding small urban watercourses. They are specifically tailored to the design of spaces around the Kumodraz stream but can be adjusted for use around other streams in Belgrade, with the necessary modifications. For broader application in different contexts, it is essential to make adjustments that align with the specific context and update the input data based on the current state of the research and surveys. These guidelines also serve as an example of the implementation of the methodology described in this research.

6.3. Role of Urban Design in Creating Resilient Public Open Spaces Surrounding Urban Small Watercourses

The natural design of the stream, wetland ecosystems and the preservation of green areas will significantly enhance the quality of open public spaces surrounding streams and create opportunities for their use for recreation and relaxation as an integral part of Belgrade’s blue–green corridors [25,28,60]. In accordance with planning documentation [59,60,62,63] and existing research in related fields [8,9,24,25,28,29], the role of urban design is recognized as crucial in the revitalization of areas surrounding small urban watercourses.

Based on the guidelines as presented above, a generalization process was undertaken and the principles as well as the role of urban design in the revitalization of open public spaces along small waterways towards resilience were redefined. In addition to the basic purpose of increasing the capacity of spaces and creating high-quality open public spaces, urban design can also contribute to other aspects of the process of revitalization in the areas surrounding the small urban watercourses.

• To harmonize different goals in the design of a space and reconcile numerous functions in order to create high-quality, resilient spaces. Open public spaces with a large number of functions require a specific approach to design that is able to respond to many different goals: to improve the quality of life for citizens, to connect and support watercourse revitalization and improvement projects with urban regeneration projects, to create a system of recreational areas and to protect from floods, reduce pollution and safely restore the entire ecosystem. These are all coordinated within the concept of quality open public spaces. This perspective aligns with current urban design research by recognizing the various roles of open public spaces [35,64,65].
• To integrate open public spaces functionally and spatially into the wider urban context and create a basis for further capacity building. The areas surrounding small urban waterways are often barriers to the overall circulation of people and goods and cannot connect with other parts of the city. Instead, organized and functionally developed open public spaces must be redesigned to be visually and functionally connecting elements that, while ensuring accessibility, encourage citizens to visit and enjoy them. Research that addresses various forms of spatial barriers offers a range of measures to overcome them [4,5,50,64,66].
• To achieve functional and visual unity in the design of individual open spaces along the watercourse, but, at the same time, to ensure that they are not monotonous and uniform. The watercourse is an element that binds several different urban entities together with ecosystems along the course into a whole. An approach that emphasizes the importance of considering the entire watercourse as a single entity is recognized in related research [3,7,24].
• To achieve the functional and visual connection of the left and right banks, including the watercourse and the surrounding environment. In contrast to large rivers, where the left and right banks are far apart, in the case of small watercourses, the banks and the water must be treated as an inseparable entity that has a unique shape. From the point of view of flood protection, this transverse connection is very important because it creates a connection between the water and floodplains, directs the water movement and connects the water and riparian ecosystems.
• To ensure the functionality of open public spaces under different circumstances caused by large variations in water levels, to harmonize changes and to ensure, to the highest possible extent, the high-quality use of the space during the year and in periods after disturbances. In the case of small watercourses, there are large differences in the water level during the year [28].
• To realize the visual and functional integration of systems used in flood protection, including green infrastructure, to increase the attractiveness and appealing qualities of the areas surrounding small urban watercourses. Several studies recognize the importance of integrating green infrastructure in areas surrounding watercourses [2,38,61]. However, it is essential for this integration to be attractive. To improve their quality, flood, erosion and heatwave protection elements should be given the ability to perform multiple functions at the same time. It is important to enable citizens to access these systems and use the services that they provide.
• To encourage, with adequate spatial patterns, the development of the largest possible number of diverse activities, coordinated in space and time, for the purpose of greater attendance at the space and raising its quality and resilience. Grouping complementary activities and separating conflicting ones in space and time encourages stronger social interactions and connections.
• To make the space capable of providing better information and awareness-building and to stimulate openness, communication and self-organization among citizens so that, with proper information and knowledge, they are more adequately prepared to face the disturbances that are likely to arise in the future.

The challenges encountered in preparing and conducting this research are exemplified in the difficulties that occurred during data collection, which are important from the point of view of the urban design methodology applied in the Kumodraz watercourse case study. This was mainly due to the difficulty in accessing the sites along the watercourse valley, where several micro-sites were impossible to visit. Another challenging issue was the survey. The pilot survey used here was based on and conducted on a limited sample. For this reason, more advanced additional research is needed that included a larger number of respondents, focusing on selected target groups of respondents, as a further extension of the research presented in this work. A set of comparable case studies at different locations in the area of Belgrade, on one hand, and in multiple cities in Serbia, on the other, would be useful in order to obtain more reliable results. These steps would advance the points of view originally developed here and enable the development of a general approach to the issue of urban design in areas surrounding small urban watercourses.

Defining the role of urban design in the process of the revitalization of open public spaces in areas surrounding small urban water bodies can be seen as a starting point for further research. The results presented here can be used as an incentive in areas facing similar challenges and help to establish an integral approach to the revitalization of the areas surrounding small urban watercourses in a local context. This research opens up questions for new research that could explore measures to establish an integrated approach and interdisciplinary collaboration. The pilot survey conducted in this study provides some input and raises a number of questions regarding how to involve citizens in the urban design of these spaces.