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Volume 38, Issue 4 (2023)
GeoRes 2023, 38(4): 491-498 |
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Received: 2023/10/10 | Accepted: 2023/12/8 | Published: 2023/12/16
Received: 2023/10/10 | Accepted: 2023/12/8 | Published: 2023/12/16
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Salarian H, Memarian G, Mohammad Moradi A. Physical And Social Feasibility Study Of The Use Of Rainwater Harvesting System In The Housing Of Mazandaran Cities Based On Geographical Differences. GeoRes 2023; 38 (4) :491-498
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1- Department of Architecture, Faculty of Architecture and Urban Planning, Iran University of Science and Technology, Tehran, Iran
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Introduction
In recent decades, climate change manifested in droughts, reduced water resources, and floods has increased the importance of addressing water-related issues across various fields, including geography and urban planning. In Iran’s arid and semi-arid climates, water conservation and management in the residential sector have long been recognized as crucial by experts. However, due to the prevailing perception of abundant water in humid regions, particularly along the Caspian Sea coast, such considerations are often overlooked.
Contrary to the common belief of plentiful water resources in Mazandaran Province, climate change has placed this region at risk of water scarcity and drought. Drought zoning studies indicate that slightly more than 50% of Mazandaran’s area falls within the very dry to dry-normal categories [Hakimdost et al., 2015]. In recent years, this trend has spread unprecedentedly across all monitoring stations in the province, revealing an overarching “hyper-arid” trajectory [Mohammadpour & Bozorgmehr, 2014].
The unique climate of the Caspian littoral has historically influenced local housing typologies in conjunction with cultural and social factors. Ensuring comfort in this humid and rainy environment was a challenge that traditional architecture largely managed to address [Qobadian, 1993]. A close examination of vernacular settlements shows that both directly and indirectly, most spatial elements and relationships in the region are shaped by water [Diba & Yaghini, 1993]. From large-scale urban structures to micro-components, water has been a defining force a fact that is equally evident in contemporary urban planning in Mazandaran. This underlines the necessity of studying the role of water in the region.
Over recent decades, housing patterns in Mazandaran have undergone major transformations. These changes have altered urban infrastructure, increasing impermeable surfaces such as rooftops, roads, parking lots, and pavements. Consequently, natural filtration processes, infiltration capacity, and soil water retention have been replaced with compacted soil and impermeable layers. This shift has led to greater volumes of excess water flowing rapidly toward surface water receptors [Lamera et al., 2014]. Meanwhile, recent studies have demonstrated that the volume of water that can be harvested from impermeable rooftops and similar surfaces is significant, and scaling these results across urban areas could provide a practical solution to the province’s growing water supply crisis [Pahlavani et al., 2016].
Among the various approaches to residential water management, this paper focuses on rainwater harvesting (RWH) systems. Broadly defined, RWH refers to the collection and storage of rainwater for reuse. Historically, this practice was employed for drinking and irrigation. Numerous studies, both domestic and international, have confirmed the effectiveness of RWH, particularly in residential contexts [Fonseca et al., 2017; Amos et al., 2018; Noori, 2018].
Technical, economic, and environmental feasibility of RWH systems has been widely evaluated [Akter & Ahmed, 2015; Bailey et al., 2018; Taran & Mahtabi, 2016]. For instance, the positive impact of green roofs on stormwater management has been frequently highlighted [Lamera et al., 2014; Polinsky, 2009]. RWH systems are generally categorized into three types: large catchment systems, rooftop collection systems, and courtyard-based systems.
Research by Silva et al. [2015], Fonseca et al. [2017], and Komeh et al. [2015] confirm the efficiency of RWH in residential buildings, with particularly strong advantages in regions of moderate to high rainfall. Abedzadeh et al. [2015] also emphasize that in Mazandaran, beyond being technically feasible, RWH systems are economically justified.
Studies further stress the importance of understanding the components and physical features of RWH systems, since any planning or regulatory framework must be compatible with their technical requirements. For example, Amos et al. and Silva et al. identified the main components as: catchment surface, gutters, filtration unit, storage tank, delivery system, and purification unit. Beyond mechanical performance, the form and dimensions of these components can influence housing design and modifications, requiring careful consideration [Silva et al., 2015; Amos et al., 2018].
In Mazandaran’s cities, the shift from traditional to industrial building materials has significantly altered runoff patterns. The expansion of asphalt and other impermeable surfaces has increased urban runoff, thereby intensifying the demand for water management systems. While construction materials slightly affect harvested water quality (e.g., Mendez et al. [2011] found that metal roofs yield higher-quality rainwater than other materials), they do not eliminate the need for purification. In general, the transition from absorbent to impermeable materials presents both opportunities and challenges: while it reduces groundwater recharge and increases surface evaporation [Narin et al., 2005], it simultaneously enhances runoff volumes that could be captured through RWH.
In summary, vernacular housing in Mazandaran historically adopted a defensive approach to water, primarily seeking to divert rainfall and prevent structural damage. However, under current climate change conditions, broader aspects of water resource management including stormwater collection and wastewater disposal must also be addressed. Against this backdrop, the present study investigates the relationship between housing morphology, climatic and geographic conditions, and the potential for developing residential rainwater harvesting systems in Mazandaran’s urban areas. The aim is to analyze and compare the physical and social aspects of three cities in the province, categorized by their geographic conditions, to assess their potential for implementing RWH systems.
Methodology
The present study falls within the domain of applied research and was conducted between 2017 and 2021 in the cities of Noor, Amol, and Larijan. The research data were categorized into three groups:
The overall study methodology for evaluating rainwater harvesting feasibility involved identifying three main components: source (rainfall), demand (water needs for drinking, non-drinking, or irrigation), and collection and distribution system. Data for these components were obtained as follows:
a. Annual rainfall: Average annual precipitation data for each study area were collected.
b. Harvested rainwater volume: Calculated using the annual rainfall, catchment area, and runoff coefficient according to Equation 1:
S=Cr×A×R
Where:
S=max(∑Vd−∑Vs)
Where:
The Kolmogorov-Smirnov test was employed to compare data distributions with normal distribution. Parametric tests (e.g., one-sample t-test) and non-parametric tests (e.g., Wilcoxon and Kruskal-Wallis tests) were used to examine hypotheses. Data analysis was performed using SPSS version 24. To ensure validity, the draft questionnaire was reviewed by faculty members and housing and architecture experts, and their suggestions were incorporated. Cronbach’s alpha was used to assess reliability, and all sections had alpha values above 0.7.
The study area included the cities of Noor, Amol, and Larijan in Mazandaran Province. These cities were selected due to their geographical diversity, representing coastal (plain), foothill, and mountainous zones within a relatively small geographic area. For RWH feasibility assessment, the researcher-distributed questionnaire was administered in the three cities. Sample size was determined using Morgan’s table, resulting in 384 participants per city.
Findings
The findings can be categorized according to three data groups: physical, technical, and social. In the process of ranking physical variables using the Delphi method, consensus among experts was achieved on seven sub-indicators, resulting in panel agreement on the architectural criteria effective for rainwater harvesting (RWH).
Calculations were based on the area of urban land uses, which were extracted from city maps. Since residential land-use areas included both courtyard and rooftop surfaces, aerial imagery was used to differentiate and determine the roof-to-courtyard ratio. Using Google Earth images, selected houses were analyzed to separate courtyard and building areas, and the percentage of rooftop area relative to the courtyard was calculated. Each city was divided into three zones, and the average area of each zone was determined.
After calculating the mean area in each study zone, the amount of harvestable water dependent on rainfall and rooftop area was computed for each month of the study years.
To determine the appropriate tank volume for the RWH system, tank volume optimization was conducted using the mass curve method. This method maximizes the difference between cumulative inflow and cumulative water demand over the active storage period, which is influenced by factors such as building area, number of residents, and water consumption. Optimal tank volumes were calculated both for 100% consumption fulfillment and for a 25% reduction in demand during rainy seasons.
Based on the data analysis, the mean optimal tank volumes in Larijan for the northern, central, and southern zones were 6,378, 5,426, and 6,138 liters, respectively. For Amol, the volumes were 9,250, 8,193, and 8,454 liters, and for Noor, 7,900, 6,247, and 8,453 liters for the respective zones.
The findings indicated that rainwater harvesting provides an effective solution compatible with the physical housing structure in Mazandaran, supporting optimal water management and conservation.
For the social dimension, the study variables included multiple sub-indicators. Considering the central limit theorem, the mean values followed a normal distribution, with 3 considered as the neutral midpoint. The test values for the three variables were below 0.05, indicating statistical significance. In all urban areas, resident participation was above average, with a mean of 3.529. However, managerial capacity was below average, while physical compatibility was above average (mean=3.394). This trend was consistent across Larijan, Amol, and Noor.
The social feasibility assessment indicated that citizens were cooperative and participatory regarding the RWH system. Physical compatibility was above average, making the development of such systems feasible. However, the lack of municipal management capacity was identified as the main barrier to implementing RWH systems in residential areas of Mazandaran.
Considering the existing conditions and the presence of both social and physical capacity for RWH adoption, technical findings regarding average catchment area and tank volume were identified as the two key physical elements in residential housing within the study area.
Discussion
The aim of this study was to analyze and assess the feasibility of implementing rainwater harvesting (RWH) systems in residential areas of Larijan, Amol, and Noor in Mazandaran Province based on physical, social, and managerial potential. Accordingly, the main findings were presented in three categories: physical, technical, and social.
The overall results of this research regarding the effectiveness of RWH systems in water management and reduction of environmental pollution are consistent with studies by Kuntz and Ghisi [Kuntz & Ghisi, 2020], Taran and Mahtabi [Taran & Mahtabi, 2016], and Bailey et al. [Bailey et al., 2018].
The most important physical variables influencing water management in Mazandaran’s housing included roof area, roof slope, yard and courtyard dimensions, site slope, gutters, proportions and dimensions, and insulation details. Some of these variables have been individually identified in other studies. For example, Che-Ani et al. [Che-Ani et al., 2009] highlight catchment area and gutters, which were also mentioned by Fonseca et al. [Fonseca et al., 2017] and Silva et al. [Silva et al., 2015]. However, similarity in other variables was limited, likely due to differences in research perspectives. This study approached the topic from an urban planning perspective, whereas most existing studies focus on technical aspects of water management in residential buildings. This distinction becomes clearer when compared with Elliott’s study [Elliott, 2014], which examined rural housing in Ghana.
On the other hand, in terms of the physical dimension, Angrill et al. demonstrate that rooftop tank solutions have less impact than underground tanks, as they increase energy and material efficiency, but their structural reinforcement needs can be addressed through safety factors without a tank [Angrill et al., 2017]. In the study by Şahin and Manioğlu, the relationship between harvested rainwater volume and building form across different climatic regions are comparatively analyzed [Şahin & Manioğlu, 2019]. These aspects were not addressed in the present study and could be explored further in dedicated research.
The mean optimal tank volume for warm seasons was 5,981 liters in Larijan, 8,632 liters in Amol, and 7,533 liters in Noor. For cold seasons, when water demand is lower, volumes were 4,486, 6,474, and 5,650 liters, respectively. These calculations are highly context-specific, depending on rainfall and local housing forms, and therefore are not directly comparable with other studies. However, Mollaei et al. have reached different volumes in various areas of Tehran using a similar method, attributing differences to variations in rainfall and topography [Mollaei et al., 2020]. Similar variability is reported in Shokati et al. and Pahlavani et al. [Pahlavani et al., 2016; Shokati et al., 2022].
The findings also indicated that system reliability increases directly with tank volume. However, as tank volume grows, the rate of increase gradually diminishes until reaching a plateau. This trend aligns with other studies [Mehrabadi et al., 2013; Bashar et al., 2018].
Regarding the social and institutional dimension, the study revealed above-average citizen participation in all three cities concerning RWH system development. This finding aligns with Masoudi, who observes public involvement in other water management projects [Masoudi, 2022]. However, Sheikh have argued that despite public acceptance of such systems, limited citizen knowledge and technical expertise were key barriers to their adoption [Sheikh, 2020; Sheikh, 2021].
Concerning the relationship between urban management and RWH system development, no prior studies were found in Iran. Soler et al. in Berlin have highlighted social participation as a primary factor in urban water management, a trend not observed in Iranian cities [Soler et al., 2018]. Additionally, Lee et al. and Campisano et al. [Campisano et al., 2017; Lee et al., 2016] have emphasized the importance of supportive policies, citizen training, and the provision of necessary infrastructure for RWH development issues not addressed in the present study.
The main limitation of this research was access to diverse geographic areas within Mazandaran Province. Therefore, future studies could apply this methodology to other cities in Mazandaran or Gilan to provide results applicable to similar climatic zones.
Conclusion
Citizen participation and the physical compatibility of residential buildings were assessed as above average. The structural characteristics of housing in the cities of Mazandaran provide favorable conditions for the implementation of rainwater harvesting (RWH) systems. However, the limited capacity of urban management in the studied cities remains a significant barrier to the development and expansion of these systems.
Acknowledgments: No acknowledgments were reported by the authors.
Ethical Permission: The authors adhered to scientific ethical principles, including honesty, confidentiality, and integrity.
Conflict of Interest: This article is based on the first author’s PhD dissertation titled “Identification and Analysis of Mazandaran Vernacular Architectural Elements with the Aim of Providing Architectural Solutions for Water Resource Management and Utilization in Contemporary Housing”, supervised by the second and third authors at Iran University of Science and Technology.
Author Contributions: Salarian (first author), Main Researcher (50%); Memarian GH (second author), Methodologist/Assistant Researcher (25%); Mohammad Moradi A (third author), Introduction Writer/Discussion Writer (25%)
Funding: No funding was reported by the authors.
In recent decades, climate change manifested in droughts, reduced water resources, and floods has increased the importance of addressing water-related issues across various fields, including geography and urban planning. In Iran’s arid and semi-arid climates, water conservation and management in the residential sector have long been recognized as crucial by experts. However, due to the prevailing perception of abundant water in humid regions, particularly along the Caspian Sea coast, such considerations are often overlooked.
Contrary to the common belief of plentiful water resources in Mazandaran Province, climate change has placed this region at risk of water scarcity and drought. Drought zoning studies indicate that slightly more than 50% of Mazandaran’s area falls within the very dry to dry-normal categories [Hakimdost et al., 2015]. In recent years, this trend has spread unprecedentedly across all monitoring stations in the province, revealing an overarching “hyper-arid” trajectory [Mohammadpour & Bozorgmehr, 2014].
The unique climate of the Caspian littoral has historically influenced local housing typologies in conjunction with cultural and social factors. Ensuring comfort in this humid and rainy environment was a challenge that traditional architecture largely managed to address [Qobadian, 1993]. A close examination of vernacular settlements shows that both directly and indirectly, most spatial elements and relationships in the region are shaped by water [Diba & Yaghini, 1993]. From large-scale urban structures to micro-components, water has been a defining force a fact that is equally evident in contemporary urban planning in Mazandaran. This underlines the necessity of studying the role of water in the region.
Over recent decades, housing patterns in Mazandaran have undergone major transformations. These changes have altered urban infrastructure, increasing impermeable surfaces such as rooftops, roads, parking lots, and pavements. Consequently, natural filtration processes, infiltration capacity, and soil water retention have been replaced with compacted soil and impermeable layers. This shift has led to greater volumes of excess water flowing rapidly toward surface water receptors [Lamera et al., 2014]. Meanwhile, recent studies have demonstrated that the volume of water that can be harvested from impermeable rooftops and similar surfaces is significant, and scaling these results across urban areas could provide a practical solution to the province’s growing water supply crisis [Pahlavani et al., 2016].
Among the various approaches to residential water management, this paper focuses on rainwater harvesting (RWH) systems. Broadly defined, RWH refers to the collection and storage of rainwater for reuse. Historically, this practice was employed for drinking and irrigation. Numerous studies, both domestic and international, have confirmed the effectiveness of RWH, particularly in residential contexts [Fonseca et al., 2017; Amos et al., 2018; Noori, 2018].
Technical, economic, and environmental feasibility of RWH systems has been widely evaluated [Akter & Ahmed, 2015; Bailey et al., 2018; Taran & Mahtabi, 2016]. For instance, the positive impact of green roofs on stormwater management has been frequently highlighted [Lamera et al., 2014; Polinsky, 2009]. RWH systems are generally categorized into three types: large catchment systems, rooftop collection systems, and courtyard-based systems.
Research by Silva et al. [2015], Fonseca et al. [2017], and Komeh et al. [2015] confirm the efficiency of RWH in residential buildings, with particularly strong advantages in regions of moderate to high rainfall. Abedzadeh et al. [2015] also emphasize that in Mazandaran, beyond being technically feasible, RWH systems are economically justified.
Studies further stress the importance of understanding the components and physical features of RWH systems, since any planning or regulatory framework must be compatible with their technical requirements. For example, Amos et al. and Silva et al. identified the main components as: catchment surface, gutters, filtration unit, storage tank, delivery system, and purification unit. Beyond mechanical performance, the form and dimensions of these components can influence housing design and modifications, requiring careful consideration [Silva et al., 2015; Amos et al., 2018].
In Mazandaran’s cities, the shift from traditional to industrial building materials has significantly altered runoff patterns. The expansion of asphalt and other impermeable surfaces has increased urban runoff, thereby intensifying the demand for water management systems. While construction materials slightly affect harvested water quality (e.g., Mendez et al. [2011] found that metal roofs yield higher-quality rainwater than other materials), they do not eliminate the need for purification. In general, the transition from absorbent to impermeable materials presents both opportunities and challenges: while it reduces groundwater recharge and increases surface evaporation [Narin et al., 2005], it simultaneously enhances runoff volumes that could be captured through RWH.
In summary, vernacular housing in Mazandaran historically adopted a defensive approach to water, primarily seeking to divert rainfall and prevent structural damage. However, under current climate change conditions, broader aspects of water resource management including stormwater collection and wastewater disposal must also be addressed. Against this backdrop, the present study investigates the relationship between housing morphology, climatic and geographic conditions, and the potential for developing residential rainwater harvesting systems in Mazandaran’s urban areas. The aim is to analyze and compare the physical and social aspects of three cities in the province, categorized by their geographic conditions, to assess their potential for implementing RWH systems.
Methodology
The present study falls within the domain of applied research and was conducted between 2017 and 2021 in the cities of Noor, Amol, and Larijan. The research data were categorized into three groups:
- Physical housing data for the cities of Noor, Amol, and Larijan, collected through indirect observation by the researcher and prioritized using the Delphi method.
- Technical data, calculated based on rainfall statistics from 2017 to 2021.
- Feasibility data for implementing rainwater harvesting (RWH) systems, collected through a social questionnaire.
The overall study methodology for evaluating rainwater harvesting feasibility involved identifying three main components: source (rainfall), demand (water needs for drinking, non-drinking, or irrigation), and collection and distribution system. Data for these components were obtained as follows:
a. Annual rainfall: Average annual precipitation data for each study area were collected.
b. Harvested rainwater volume: Calculated using the annual rainfall, catchment area, and runoff coefficient according to Equation 1:
S=Cr×A×R
Where:
- S = harvested rainwater volume (m³/year)
- Cr = runoff coefficient
- R = rainfall (mm)
- A = catchment area (m²)
S=max(∑Vd−∑Vs)
Where:
- S = required or stored water volume (m³)
- Vd = inflow volume (m³)
- s = effective storage volume (m³)
The Kolmogorov-Smirnov test was employed to compare data distributions with normal distribution. Parametric tests (e.g., one-sample t-test) and non-parametric tests (e.g., Wilcoxon and Kruskal-Wallis tests) were used to examine hypotheses. Data analysis was performed using SPSS version 24. To ensure validity, the draft questionnaire was reviewed by faculty members and housing and architecture experts, and their suggestions were incorporated. Cronbach’s alpha was used to assess reliability, and all sections had alpha values above 0.7.
The study area included the cities of Noor, Amol, and Larijan in Mazandaran Province. These cities were selected due to their geographical diversity, representing coastal (plain), foothill, and mountainous zones within a relatively small geographic area. For RWH feasibility assessment, the researcher-distributed questionnaire was administered in the three cities. Sample size was determined using Morgan’s table, resulting in 384 participants per city.
Findings
The findings can be categorized according to three data groups: physical, technical, and social. In the process of ranking physical variables using the Delphi method, consensus among experts was achieved on seven sub-indicators, resulting in panel agreement on the architectural criteria effective for rainwater harvesting (RWH).
Calculations were based on the area of urban land uses, which were extracted from city maps. Since residential land-use areas included both courtyard and rooftop surfaces, aerial imagery was used to differentiate and determine the roof-to-courtyard ratio. Using Google Earth images, selected houses were analyzed to separate courtyard and building areas, and the percentage of rooftop area relative to the courtyard was calculated. Each city was divided into three zones, and the average area of each zone was determined.
After calculating the mean area in each study zone, the amount of harvestable water dependent on rainfall and rooftop area was computed for each month of the study years.
To determine the appropriate tank volume for the RWH system, tank volume optimization was conducted using the mass curve method. This method maximizes the difference between cumulative inflow and cumulative water demand over the active storage period, which is influenced by factors such as building area, number of residents, and water consumption. Optimal tank volumes were calculated both for 100% consumption fulfillment and for a 25% reduction in demand during rainy seasons.
Based on the data analysis, the mean optimal tank volumes in Larijan for the northern, central, and southern zones were 6,378, 5,426, and 6,138 liters, respectively. For Amol, the volumes were 9,250, 8,193, and 8,454 liters, and for Noor, 7,900, 6,247, and 8,453 liters for the respective zones.
The findings indicated that rainwater harvesting provides an effective solution compatible with the physical housing structure in Mazandaran, supporting optimal water management and conservation.
For the social dimension, the study variables included multiple sub-indicators. Considering the central limit theorem, the mean values followed a normal distribution, with 3 considered as the neutral midpoint. The test values for the three variables were below 0.05, indicating statistical significance. In all urban areas, resident participation was above average, with a mean of 3.529. However, managerial capacity was below average, while physical compatibility was above average (mean=3.394). This trend was consistent across Larijan, Amol, and Noor.
The social feasibility assessment indicated that citizens were cooperative and participatory regarding the RWH system. Physical compatibility was above average, making the development of such systems feasible. However, the lack of municipal management capacity was identified as the main barrier to implementing RWH systems in residential areas of Mazandaran.
Considering the existing conditions and the presence of both social and physical capacity for RWH adoption, technical findings regarding average catchment area and tank volume were identified as the two key physical elements in residential housing within the study area.
Discussion
The aim of this study was to analyze and assess the feasibility of implementing rainwater harvesting (RWH) systems in residential areas of Larijan, Amol, and Noor in Mazandaran Province based on physical, social, and managerial potential. Accordingly, the main findings were presented in three categories: physical, technical, and social.
The overall results of this research regarding the effectiveness of RWH systems in water management and reduction of environmental pollution are consistent with studies by Kuntz and Ghisi [Kuntz & Ghisi, 2020], Taran and Mahtabi [Taran & Mahtabi, 2016], and Bailey et al. [Bailey et al., 2018].
The most important physical variables influencing water management in Mazandaran’s housing included roof area, roof slope, yard and courtyard dimensions, site slope, gutters, proportions and dimensions, and insulation details. Some of these variables have been individually identified in other studies. For example, Che-Ani et al. [Che-Ani et al., 2009] highlight catchment area and gutters, which were also mentioned by Fonseca et al. [Fonseca et al., 2017] and Silva et al. [Silva et al., 2015]. However, similarity in other variables was limited, likely due to differences in research perspectives. This study approached the topic from an urban planning perspective, whereas most existing studies focus on technical aspects of water management in residential buildings. This distinction becomes clearer when compared with Elliott’s study [Elliott, 2014], which examined rural housing in Ghana.
On the other hand, in terms of the physical dimension, Angrill et al. demonstrate that rooftop tank solutions have less impact than underground tanks, as they increase energy and material efficiency, but their structural reinforcement needs can be addressed through safety factors without a tank [Angrill et al., 2017]. In the study by Şahin and Manioğlu, the relationship between harvested rainwater volume and building form across different climatic regions are comparatively analyzed [Şahin & Manioğlu, 2019]. These aspects were not addressed in the present study and could be explored further in dedicated research.
The mean optimal tank volume for warm seasons was 5,981 liters in Larijan, 8,632 liters in Amol, and 7,533 liters in Noor. For cold seasons, when water demand is lower, volumes were 4,486, 6,474, and 5,650 liters, respectively. These calculations are highly context-specific, depending on rainfall and local housing forms, and therefore are not directly comparable with other studies. However, Mollaei et al. have reached different volumes in various areas of Tehran using a similar method, attributing differences to variations in rainfall and topography [Mollaei et al., 2020]. Similar variability is reported in Shokati et al. and Pahlavani et al. [Pahlavani et al., 2016; Shokati et al., 2022].
The findings also indicated that system reliability increases directly with tank volume. However, as tank volume grows, the rate of increase gradually diminishes until reaching a plateau. This trend aligns with other studies [Mehrabadi et al., 2013; Bashar et al., 2018].
Regarding the social and institutional dimension, the study revealed above-average citizen participation in all three cities concerning RWH system development. This finding aligns with Masoudi, who observes public involvement in other water management projects [Masoudi, 2022]. However, Sheikh have argued that despite public acceptance of such systems, limited citizen knowledge and technical expertise were key barriers to their adoption [Sheikh, 2020; Sheikh, 2021].
Concerning the relationship between urban management and RWH system development, no prior studies were found in Iran. Soler et al. in Berlin have highlighted social participation as a primary factor in urban water management, a trend not observed in Iranian cities [Soler et al., 2018]. Additionally, Lee et al. and Campisano et al. [Campisano et al., 2017; Lee et al., 2016] have emphasized the importance of supportive policies, citizen training, and the provision of necessary infrastructure for RWH development issues not addressed in the present study.
The main limitation of this research was access to diverse geographic areas within Mazandaran Province. Therefore, future studies could apply this methodology to other cities in Mazandaran or Gilan to provide results applicable to similar climatic zones.
Conclusion
Citizen participation and the physical compatibility of residential buildings were assessed as above average. The structural characteristics of housing in the cities of Mazandaran provide favorable conditions for the implementation of rainwater harvesting (RWH) systems. However, the limited capacity of urban management in the studied cities remains a significant barrier to the development and expansion of these systems.
Acknowledgments: No acknowledgments were reported by the authors.
Ethical Permission: The authors adhered to scientific ethical principles, including honesty, confidentiality, and integrity.
Conflict of Interest: This article is based on the first author’s PhD dissertation titled “Identification and Analysis of Mazandaran Vernacular Architectural Elements with the Aim of Providing Architectural Solutions for Water Resource Management and Utilization in Contemporary Housing”, supervised by the second and third authors at Iran University of Science and Technology.
Author Contributions: Salarian (first author), Main Researcher (50%); Memarian GH (second author), Methodologist/Assistant Researcher (25%); Mohammad Moradi A (third author), Introduction Writer/Discussion Writer (25%)
Funding: No funding was reported by the authors.
Keywords:
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