Elhadi Mohsen Hassan Abdalla, T. Muthanna, K. Alfredsen, E. Sivertsen
The common approach of the hydrologic design of permeable pavements (PPs) uses synthetic rainfall events. This study assessed the validity of the design approach using synthetic rainfall events for undrained PP. Synthetic rainfall events (25-year return period) were used to design undrained pavements for five Norwegian cities. The effectiveness of these pavements was tested using long-term simulation (12–30 years) with high temporal resolution (1 min). The Storm Water Management Model (SWMM) was used to generate time series of surface runoff for PPs and flow duration curves were applied to analyse the hydrological performances. Designing PP using synthetic rainfall events was found to underestimate the storage layer depth of the permeable pavements leading to the frequent occurrence of surface runoff, which is considered a failure of the hydrologic design of undrained pavements. Long-term simulation of surface runoff was found to provide valuable information for the hydrologic design of PP and can be used as a basis for the PP hydrologic design. In the future, it is recommended to use long-term precipitation data generated from climate change models to incorporate the effect of climate change in the design of PP.
{"title":"Towards improving the hydrologic design of permeable pavements","authors":"Elhadi Mohsen Hassan Abdalla, T. Muthanna, K. Alfredsen, E. Sivertsen","doi":"10.2166/bgs.2022.004","DOIUrl":"https://doi.org/10.2166/bgs.2022.004","url":null,"abstract":"\u0000 The common approach of the hydrologic design of permeable pavements (PPs) uses synthetic rainfall events. This study assessed the validity of the design approach using synthetic rainfall events for undrained PP. Synthetic rainfall events (25-year return period) were used to design undrained pavements for five Norwegian cities. The effectiveness of these pavements was tested using long-term simulation (12–30 years) with high temporal resolution (1 min). The Storm Water Management Model (SWMM) was used to generate time series of surface runoff for PPs and flow duration curves were applied to analyse the hydrological performances. Designing PP using synthetic rainfall events was found to underestimate the storage layer depth of the permeable pavements leading to the frequent occurrence of surface runoff, which is considered a failure of the hydrologic design of undrained pavements. Long-term simulation of surface runoff was found to provide valuable information for the hydrologic design of PP and can be used as a basis for the PP hydrologic design. In the future, it is recommended to use long-term precipitation data generated from climate change models to incorporate the effect of climate change in the design of PP.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43484655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Green roofs are a popular way to include nature in an urban environment. A reduction in stormwater runoff peaks and volumes are among the benefits one can expect. How is runoff from green roofs in the cold and snow-covered part of the year, when growth media freeze, plants are dormant and covered with melting snow? This paper investigates 11 years of runoff from three green extensive roofs in Oslo, Norway. Precipitation through the snow-covered period (SCP) was approximately one-third of the annual precipitation (970 mm). When runoff from green roofs is compared to runoff from a non-vegetated bitumen roof, retention of 16–31% is seen through the SCP, depending on the drainage system, fabric, soil quality, and depth. The difference in buildup did not influence the detention of the largest runoff intensities. Dampening the runoff happened even though the substrate was saturated. According to the soil moisture sensors, the capacity of the roof with the highest water retention could be increased even more if drainage could be restricted. The runoff from bitumen roofs always exceeded the runoff from green roofs. As a result, harmful inundation may be reduced in a part of the year when infiltration is restricted due to frost.
{"title":"Retention of snowmelt and rain from extensive green roofs during snow-covered periods","authors":"B. Braskerud, K. Paus","doi":"10.2166/bgs.2022.011","DOIUrl":"https://doi.org/10.2166/bgs.2022.011","url":null,"abstract":"\u0000 Green roofs are a popular way to include nature in an urban environment. A reduction in stormwater runoff peaks and volumes are among the benefits one can expect. How is runoff from green roofs in the cold and snow-covered part of the year, when growth media freeze, plants are dormant and covered with melting snow? This paper investigates 11 years of runoff from three green extensive roofs in Oslo, Norway. Precipitation through the snow-covered period (SCP) was approximately one-third of the annual precipitation (970 mm). When runoff from green roofs is compared to runoff from a non-vegetated bitumen roof, retention of 16–31% is seen through the SCP, depending on the drainage system, fabric, soil quality, and depth. The difference in buildup did not influence the detention of the largest runoff intensities. Dampening the runoff happened even though the substrate was saturated. According to the soil moisture sensors, the capacity of the roof with the highest water retention could be increased even more if drainage could be restricted. The runoff from bitumen roofs always exceeded the runoff from green roofs. As a result, harmful inundation may be reduced in a part of the year when infiltration is restricted due to frost.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45271060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water distribution networks (WDNs) are an important part of water distribution systems and are responsible for water transportation from the reservoirs to the demand nodes at adequate pressure and velocity. In the present paper, the synthesis of WDN is treated as an optimization problem with a mixed integer nonlinear programming formulation. The objective function to be minimized is the total network cost, considering installation and energy costs, with unknown flow directions, which is the novelty in the paper. Disjunctive programming and linearization techniques are used in the model formulation to avoid nonlinear and nonconvex problems. Two case studies are used to test the model's applicability. Results show that operational costs can represent a significant part of the total cost in sustainable networks. In the first case study, the total cost was better than the literature results (US$ 2,272,538.85 vs. US$ 2,272,387.49) and the operational costs represent ¼ of the total WDN costs. In the second case study, the operation cost corresponds to almost 2/3 of the total WDN cost. These results show the importance of considering operational costs in the WDN design. Also, the consideration of unknown flow directions can lead to better results for the network topology.
{"title":"Optimization of installation and energy costs in water distribution systems with unknown flow directions","authors":"G. Cassiolato, E. Carvalho, M. Ravagnani","doi":"10.2166/bgs.2022.003","DOIUrl":"https://doi.org/10.2166/bgs.2022.003","url":null,"abstract":"\u0000 Water distribution networks (WDNs) are an important part of water distribution systems and are responsible for water transportation from the reservoirs to the demand nodes at adequate pressure and velocity. In the present paper, the synthesis of WDN is treated as an optimization problem with a mixed integer nonlinear programming formulation. The objective function to be minimized is the total network cost, considering installation and energy costs, with unknown flow directions, which is the novelty in the paper. Disjunctive programming and linearization techniques are used in the model formulation to avoid nonlinear and nonconvex problems. Two case studies are used to test the model's applicability. Results show that operational costs can represent a significant part of the total cost in sustainable networks. In the first case study, the total cost was better than the literature results (US$ 2,272,538.85 vs. US$ 2,272,387.49) and the operational costs represent ¼ of the total WDN costs. In the second case study, the operation cost corresponds to almost 2/3 of the total WDN cost. These results show the importance of considering operational costs in the WDN design. Also, the consideration of unknown flow directions can lead to better results for the network topology.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49134803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Blue-green and blue roofs are increasingly promoted to adapt to climate change by providing multiple benefits. However, uncertainties about their design and how they differ from conventional green roofs hinder their implementation. This study investigates the potential of green, blue-green, and blue roofs to control urban stormwater and improve microclimate by monitoring their performance in Toronto, Ontario, Canada. Experimental setups were built and varied with the following design factors: substrate type and thickness, drainage layer thickness and orifice size. The results revealed that blue-green roofs with organic and FLL (blended according to the German Forschungsgesellschaft Landschaftsentiwicklung Landschaftsbau) substrates significantly improved detention compared to green roofs with similar substrates. The organic blue-green roof achieved maximum retention, but FLL blue-green roof did not have higher retention than FLL green roof. The blue roof with smaller orifices had comparable hydrologic performance to vegetated roofs but suffered from long water standing durations. Organic substrates followed by FLL substrates result in the highest air cooling in the noon, but blue roofs had the highest air cooling in the evening. In-substrate temperatures in blue-green roofs were lower than those in green roofs. Trade-offs between the benefits and drawbacks need to be considered in future designs.
{"title":"Impact of design variables on hydrologic and thermal performance of green, blue-green and blue roofs","authors":"Tamer Almaaitah, J. Drake, D. Joksimovic","doi":"10.2166/bgs.2022.016","DOIUrl":"https://doi.org/10.2166/bgs.2022.016","url":null,"abstract":"\u0000 Blue-green and blue roofs are increasingly promoted to adapt to climate change by providing multiple benefits. However, uncertainties about their design and how they differ from conventional green roofs hinder their implementation. This study investigates the potential of green, blue-green, and blue roofs to control urban stormwater and improve microclimate by monitoring their performance in Toronto, Ontario, Canada. Experimental setups were built and varied with the following design factors: substrate type and thickness, drainage layer thickness and orifice size. The results revealed that blue-green roofs with organic and FLL (blended according to the German Forschungsgesellschaft Landschaftsentiwicklung Landschaftsbau) substrates significantly improved detention compared to green roofs with similar substrates. The organic blue-green roof achieved maximum retention, but FLL blue-green roof did not have higher retention than FLL green roof. The blue roof with smaller orifices had comparable hydrologic performance to vegetated roofs but suffered from long water standing durations. Organic substrates followed by FLL substrates result in the highest air cooling in the noon, but blue roofs had the highest air cooling in the evening. In-substrate temperatures in blue-green roofs were lower than those in green roofs. Trade-offs between the benefits and drawbacks need to be considered in future designs.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":"1 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41389252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Assessing the Nature-Based Solutions (NBS) contribution to urban resilience, along with developing tools capable of demonstrating their long-term value, comprises a most needed step forward. Nevertheless, the NBS contribution to urban resilience has been yet slightly explored. Given the urban resilience complexity and multiple NBS capabilities, specific needs for a robust assessment should be investigated. This paper identifies the requirements for a comprehensive assessment of the NBS contribution to urban resilience and analyses the main assessment frameworks focused on resilience and NBS for urban drainage. First, the evolution of the resilience concept and relevant resilience assessment frameworks (RAF) are presented. Secondly, NBS challenges to enhance resilience and NBS assessment proposals are analysed. Thirdly, the attributes for assessing urban resilience and aspects to assess the NBS contribution are analysed. To conclude, a critical analysis of the assessment approaches is presented. Important challenges across the RAF have been identified, especially regarding their feasibility of application. Based on the performed analysis, most RAFs are not feasible for city benchmarking and assessing the resilience evolution over time, neither for assessing comprehensively the NBS contribution. Regarding specifically the NBS assessment proposals, just one focused on urban resilience was developed to date, which allows evaluating their contribution over time, between cities, or between different NBS.
{"title":"Nature-based solutions for water management: insights to assess the contribution to urban resilience","authors":"P. Beceiro, R. Brito, A. Galvão","doi":"10.2166/bgs.2022.009","DOIUrl":"https://doi.org/10.2166/bgs.2022.009","url":null,"abstract":"\u0000 Assessing the Nature-Based Solutions (NBS) contribution to urban resilience, along with developing tools capable of demonstrating their long-term value, comprises a most needed step forward. Nevertheless, the NBS contribution to urban resilience has been yet slightly explored. Given the urban resilience complexity and multiple NBS capabilities, specific needs for a robust assessment should be investigated. This paper identifies the requirements for a comprehensive assessment of the NBS contribution to urban resilience and analyses the main assessment frameworks focused on resilience and NBS for urban drainage. First, the evolution of the resilience concept and relevant resilience assessment frameworks (RAF) are presented. Secondly, NBS challenges to enhance resilience and NBS assessment proposals are analysed. Thirdly, the attributes for assessing urban resilience and aspects to assess the NBS contribution are analysed. To conclude, a critical analysis of the assessment approaches is presented. Important challenges across the RAF have been identified, especially regarding their feasibility of application. Based on the performed analysis, most RAFs are not feasible for city benchmarking and assessing the resilience evolution over time, neither for assessing comprehensively the NBS contribution. Regarding specifically the NBS assessment proposals, just one focused on urban resilience was developed to date, which allows evaluating their contribution over time, between cities, or between different NBS.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42086898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Gobatti, J. Martins, Maria Cristina Santana Pereira, B. C. Leite
Nature-based Solutions (NbS) Regulatory Ecosystem Services are less tangible and more complex to quantify. Among these, research to quantify water regulation services provided by Blue-Green Infrastructure is especially relevant for a range of different applications. However, to reach this quantification, experimentalists usually need to measure the flow rate, which can be costly if using high-end industry standard sensors. The present article brings, thus, a low-cost experimental setup for real-time data capture and logging using the US-025 ultrasonic sensor. The proposed setup measures a weir tanks’ water level in order to indirectly estimate the flow rate. A successful pilot experiment is described, estimating the water quantity performance of a vegetated roof in comparison to a ceramic tiled roof. For a same event, flow rate measures taken by the proposed setup are compared to readings from a rain gauge and results show a close trend. The performance of the vegetated roof has shown substantial rainfall retention and detention when compared to the ceramic roof. It is concluded that the setup is a cost-effective tool that can be attached to inlets and outlets of different NbS for characterising a range of water flow rates capable of supporting laboratory and field data capture.
{"title":"Real-time sensing and low-cost experimental setup for water quantity investigation in Nature-based Solutions","authors":"L. Gobatti, J. Martins, Maria Cristina Santana Pereira, B. C. Leite","doi":"10.2166/bgs.2022.007","DOIUrl":"https://doi.org/10.2166/bgs.2022.007","url":null,"abstract":"Nature-based Solutions (NbS) Regulatory Ecosystem Services are less tangible and more complex to quantify. Among these, research to quantify water regulation services provided by Blue-Green Infrastructure is especially relevant for a range of different applications. However, to reach this quantification, experimentalists usually need to measure the flow rate, which can be costly if using high-end industry standard sensors. The present article brings, thus, a low-cost experimental setup for real-time data capture and logging using the US-025 ultrasonic sensor. The proposed setup measures a weir tanks’ water level in order to indirectly estimate the flow rate. A successful pilot experiment is described, estimating the water quantity performance of a vegetated roof in comparison to a ceramic tiled roof. For a same event, flow rate measures taken by the proposed setup are compared to readings from a rain gauge and results show a close trend. The performance of the vegetated roof has shown substantial rainfall retention and detention when compared to the ceramic roof. It is concluded that the setup is a cost-effective tool that can be attached to inlets and outlets of different NbS for characterising a range of water flow rates capable of supporting laboratory and field data capture.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48032286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With city growth, the development of vacant or under-used land parcels is becoming more common compared to the past. The current ‘water-sensitive urban design (WSUD)’ approach to such development will improve resource efficiency, liveability, and the amenity of cities, especially natural water systems. However, there is a need to quantify the water performance of site-scale WSUD options, especially about how these options impact the ‘natural’ and ‘anthropogenic’ flows in the urban water cycle. This study reviewed research about site-scale applications, summarizing the urban water cycle studies from before development to after development. Key findings (i) include very big margin was quantified by (a) water retention (30–100%) and (b) portable water demand reduction (18–100%) for selected site-scale WSUD options through six research studies; (ii) still unclear about the selected site-scale WSUD options’ interaction performance in the urban water cycle between each water accounts, and (iii) need to clarify the site-scale WSUD option's contribution under specific rainfall scenarios. In summary, this study aims to review the literature on the urban water cycle; review the effects of site-scale WSUD options in the urban water cycle; review the water mass balance and relevant evaluation application, and highlight the opportunities for the future urban water cycle studies.
{"title":"Understanding the effects of site-scale water-sensitive urban design (WSUD) in the urban water cycle: a review","authors":"Xuliang Meng","doi":"10.2166/bgs.2022.026","DOIUrl":"https://doi.org/10.2166/bgs.2022.026","url":null,"abstract":"\u0000 With city growth, the development of vacant or under-used land parcels is becoming more common compared to the past. The current ‘water-sensitive urban design (WSUD)’ approach to such development will improve resource efficiency, liveability, and the amenity of cities, especially natural water systems. However, there is a need to quantify the water performance of site-scale WSUD options, especially about how these options impact the ‘natural’ and ‘anthropogenic’ flows in the urban water cycle. This study reviewed research about site-scale applications, summarizing the urban water cycle studies from before development to after development. Key findings (i) include very big margin was quantified by (a) water retention (30–100%) and (b) portable water demand reduction (18–100%) for selected site-scale WSUD options through six research studies; (ii) still unclear about the selected site-scale WSUD options’ interaction performance in the urban water cycle between each water accounts, and (iii) need to clarify the site-scale WSUD option's contribution under specific rainfall scenarios. In summary, this study aims to review the literature on the urban water cycle; review the effects of site-scale WSUD options in the urban water cycle; review the water mass balance and relevant evaluation application, and highlight the opportunities for the future urban water cycle studies.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43405583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Mitchell, F. Chan, Wendy Y. Chen, D. Thadani, G. Robinson, Zilin Wang, Lei Li, Xiang Li, M. Mullins, Patrick Y. K. Chau
China's Sponge City Programme (SCP) is one of the world's most ambitious sustainable urban drainage programmes. By 2030, Chinese cities must have 80% of their land drained by Blue–Green Infrastructure (BGI) to build critically needed flood resilience. Costs must be met from municipal and private finance, but BGI lacks the revenue streams of public assets like utilities, so has limited appeal to public–private partnerships. Finance options, including Green Bonds targeting institutional investors, and Payment for Urban Ecosystem Service schemes targeting local citizens and businesses, need developing. Green city branding could lever such finance but despite widespread use of green branding to attract investment, sponge branding strategies are immature, and alignment is needed in green branding between sponge project type (e.g., flagship and retrofit), financial instrument, and target financier, to develop differentiated brands that appeal to a diversity of SCP investors. With little grassroots input into city branding, and SCP problems of green gentrification, local support for SCP implementation may be at risk. This is concerning, because cities need local citizens and businesses to invest in the SCP to achieve the extensive retrofit needed, as retrofit (using small-scale BGI such as stormwater planters, de-paving, and raingardens) has little appeal for institutional investors.
{"title":"Can green city branding support China's Sponge City Programme?","authors":"G. Mitchell, F. Chan, Wendy Y. Chen, D. Thadani, G. Robinson, Zilin Wang, Lei Li, Xiang Li, M. Mullins, Patrick Y. K. Chau","doi":"10.2166/bgs.2022.005","DOIUrl":"https://doi.org/10.2166/bgs.2022.005","url":null,"abstract":"\u0000 China's Sponge City Programme (SCP) is one of the world's most ambitious sustainable urban drainage programmes. By 2030, Chinese cities must have 80% of their land drained by Blue–Green Infrastructure (BGI) to build critically needed flood resilience. Costs must be met from municipal and private finance, but BGI lacks the revenue streams of public assets like utilities, so has limited appeal to public–private partnerships. Finance options, including Green Bonds targeting institutional investors, and Payment for Urban Ecosystem Service schemes targeting local citizens and businesses, need developing. Green city branding could lever such finance but despite widespread use of green branding to attract investment, sponge branding strategies are immature, and alignment is needed in green branding between sponge project type (e.g., flagship and retrofit), financial instrument, and target financier, to develop differentiated brands that appeal to a diversity of SCP investors. With little grassroots input into city branding, and SCP problems of green gentrification, local support for SCP implementation may be at risk. This is concerning, because cities need local citizens and businesses to invest in the SCP to achieve the extensive retrofit needed, as retrofit (using small-scale BGI such as stormwater planters, de-paving, and raingardens) has little appeal for institutional investors.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47427441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stormwater harvesting systems are a viable option to adapt cities to cope with climate change and reduce pressure on water supply services. This is particularly crucial in the event of natural disasters (e.g., earthquakes, floods), where large parts of cities may become disconnected from a secure water supply for prolonged time periods. We demonstrate how optimum location, density and storage size can be determined using UrbanBEATS, a spatial planning-support system for planning and design of sustainable Blue-Green Infrastructure strategies. We investigate the Ōtākaro/Avon River catchment, Christchurch, New Zealand for the time periods 2011–2020, 2041–2050 and 2091–2100 (for the RCP 8.5 climate change scenario). For targets of 30% of potable water substitution and 70% storage volumetric reliability, we found that stormwater harvesting systems in all climate scenarios required a larger capacity compared to the baseline. Most storages achieved their set targets and were larger than the municipality's recommended 9 m3 for flood inundation, indicating that the identified storages would also reduce minor flooding while ensuring water savings. A shift in the spatial layout of modelled systems from highly distributed to more centralised, however, raises a potential conflict with disaster resilience where more local solutions would be preferable.
{"title":"Multi-scale stormwater harvesting to enhance urban resilience to climate change impacts and natural disasters","authors":"Thuy Thi Nguyen, P. Bach, M. Pahlow","doi":"10.2166/bgs.2022.008","DOIUrl":"https://doi.org/10.2166/bgs.2022.008","url":null,"abstract":"\u0000 Stormwater harvesting systems are a viable option to adapt cities to cope with climate change and reduce pressure on water supply services. This is particularly crucial in the event of natural disasters (e.g., earthquakes, floods), where large parts of cities may become disconnected from a secure water supply for prolonged time periods. We demonstrate how optimum location, density and storage size can be determined using UrbanBEATS, a spatial planning-support system for planning and design of sustainable Blue-Green Infrastructure strategies. We investigate the Ōtākaro/Avon River catchment, Christchurch, New Zealand for the time periods 2011–2020, 2041–2050 and 2091–2100 (for the RCP 8.5 climate change scenario). For targets of 30% of potable water substitution and 70% storage volumetric reliability, we found that stormwater harvesting systems in all climate scenarios required a larger capacity compared to the baseline. Most storages achieved their set targets and were larger than the municipality's recommended 9 m3 for flood inundation, indicating that the identified storages would also reduce minor flooding while ensuring water savings. A shift in the spatial layout of modelled systems from highly distributed to more centralised, however, raises a potential conflict with disaster resilience where more local solutions would be preferable.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44120825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Krivtsov, Heather Forbes, S. Birkinshaw, V. Olive, D. Chamberlain, J. Buckman, R. Yahr, S. Arthur, D. Christie, Yamina Monteiro, Cameron Diekonigin
Ponds and the adjacent green spaces are an important part of urban blue-green Infrastructure (BGI) and contribute to a number of ecosystem services, including alleviation of flood risk, amelioration of climatic fluctuations, and improvement of runoff water quality, as well as biodiversity and amenity values. Multiple benefits associated with urban ponds have only recently started to be appreciated, and examples of in-depth interdisciplinary insights remain rare. This paper gives an account of the ecosystem services provided by Blackford Pond, a semi-natural water body located within a nature reserve and nominated as a site globally important for scientific research. Despite elevated levels of polluting substances and eutrophication, the overall species richness of the site is high and the biodiversity of the locality is enhanced by the ecotone effect. The diversity of available plant hosts and substrates appears to benefit the fungal community and the abundance of aquatic invertebrate fauna appears to benefit the higher trophic levels. Hydrological modelling clearly shows that the pond increases the flood resilience of the surrounding area, despite not having been designed as a drainage feature. The application of the Natural Capital Planning Tool (NCPT) also reveals higher values (in relation to the values of amenity grassland) of such ecosystem services categories as biodiversity (+4.76 per hectare), aesthetic values (+4.67), flood risk regulation (+0.41), air quality (+0.28), local (+0.6) and global (+0.14) climate regulations. The discussion highlights a number of trade-offs among different ecosystem services (e.g. water quality vs. diatom research value, flood resilience vs. air quality and carbon capture, biodiversity of ectomycorrhizal vs. lichenised fungi), and considers which of the multiple benefits provided by the site may have not been fully reflected in NCPT calculations or the economic estimates obtained using contingent valuation (e.g. effects on hydrology, water quality, wildlife corridors, education and research value). The simultaneous consideration of biodiversity, hydrology, water chemistry and amenity, education, research and other values presented in this paper contributes towards a better understanding of the ecology and overall functioning of urban ponds, and helps to increase appreciation of their benefits and promote their public acceptability and further implementation.
{"title":"Ecosystem services provided by urban ponds and green spaces: a detailed study of a semi-natural site with global importance for research","authors":"V. Krivtsov, Heather Forbes, S. Birkinshaw, V. Olive, D. Chamberlain, J. Buckman, R. Yahr, S. Arthur, D. Christie, Yamina Monteiro, Cameron Diekonigin","doi":"10.2166/bgs.2022.021","DOIUrl":"https://doi.org/10.2166/bgs.2022.021","url":null,"abstract":"\u0000 Ponds and the adjacent green spaces are an important part of urban blue-green Infrastructure (BGI) and contribute to a number of ecosystem services, including alleviation of flood risk, amelioration of climatic fluctuations, and improvement of runoff water quality, as well as biodiversity and amenity values. Multiple benefits associated with urban ponds have only recently started to be appreciated, and examples of in-depth interdisciplinary insights remain rare. This paper gives an account of the ecosystem services provided by Blackford Pond, a semi-natural water body located within a nature reserve and nominated as a site globally important for scientific research. Despite elevated levels of polluting substances and eutrophication, the overall species richness of the site is high and the biodiversity of the locality is enhanced by the ecotone effect. The diversity of available plant hosts and substrates appears to benefit the fungal community and the abundance of aquatic invertebrate fauna appears to benefit the higher trophic levels. Hydrological modelling clearly shows that the pond increases the flood resilience of the surrounding area, despite not having been designed as a drainage feature. The application of the Natural Capital Planning Tool (NCPT) also reveals higher values (in relation to the values of amenity grassland) of such ecosystem services categories as biodiversity (+4.76 per hectare), aesthetic values (+4.67), flood risk regulation (+0.41), air quality (+0.28), local (+0.6) and global (+0.14) climate regulations. The discussion highlights a number of trade-offs among different ecosystem services (e.g. water quality vs. diatom research value, flood resilience vs. air quality and carbon capture, biodiversity of ectomycorrhizal vs. lichenised fungi), and considers which of the multiple benefits provided by the site may have not been fully reflected in NCPT calculations or the economic estimates obtained using contingent valuation (e.g. effects on hydrology, water quality, wildlife corridors, education and research value). The simultaneous consideration of biodiversity, hydrology, water chemistry and amenity, education, research and other values presented in this paper contributes towards a better understanding of the ecology and overall functioning of urban ponds, and helps to increase appreciation of their benefits and promote their public acceptability and further implementation.","PeriodicalId":9337,"journal":{"name":"Blue-Green Systems","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48641604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}