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Environmental information systems
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Objective(s)
The Stormwater Management Toolbox introduces useful approaches and concrete tools for urban stormwater management. The toolbox allows to integrate stormwater management into urban planning and development processes. For example, the Green Factor Tool allows for calculating the ratio between scored green area and total area for a lot of an urban development plan to address stormwater risks.
Short description
The Green Factor Tool is a practical and user-friendly Excel-based tool for urban planning. It aids the urban planner in increasing the quantity and quality of green areas. It helps to ensure sufficient green infrastructure for stormwater control when building new lots in a dense urban environment. The Green Factor is calculated as the ratio of the scored green area to a lot area. The target level for the lot can be achieved flexibly by the garden designer by selecting some of the 39 green elements, such as planted and maintained vegetation or various run-off water solutions, when designing the lot. The green factor can, for example, be included in the zoning regulations or used for granting concessions during a construction permit application process.
It is part of a broader toolbox that offers 16 different tools for urban stormwater management, which are classified into 1) strategic approaches, 2) planning supporting tools, 3) design/ structural solutions, and 4) assessment tools.
Free keywords
Urban stormwater
Readiness for use
Applications
In the iWater project (2015-2018), the Green Factor Tool has been adopted and piloted in several cities, mostly in Northern Europe: Riga, Jelgava, Tartu, Gävle, Söderhamn and Turku, and finally incorporated into their urban planning processes.
In the city of Helsinki, the Green Factor Tool has been updated, bringing stormwater elements a greater weight and improving the usability of the tool. The results are reflected in this report.
Strengths and weaknesses, comparative added value to other similar tools
Strengths:
(+) The Green Factor Tool can be complemented by other tools out of the iWater Integrated Stormwater management toolbox.
(+) It consists of an Excel sheet, which can be adapted to a specific local baseline (guidance on how to do so is provided).
(+) For some of the pilot cities (e.g., Riga and Turku), the tool has been integrated into the urban regulation for new development or urban regeneration areas.
Weaknesses:
(-) it does not offer the ability to monitor the implementation progress, nor evaluate the success of the green areas.
(-) The tool does not consider the local regulations that might limit what can be done in a particular urban area, even if the tool would suggest it.
Input(s)
The Green Factor Tool excel sheet needs to be filled with site information (including rainfall) and measured green urban elements such as “Preserved vegetation and soil”, “Planted and/or new vegetation”, “Pavements” or “Stormwater elements”.
Output(s)
The tool automatically weights existing and planned green areas and calculates the Green Factor. It also calculates the average runoff coefficient of the lot as an estimation. Based on the average runoff coefficient and the amount of precipitation set by the user, the approximate amount of stormwater originating from the lot is calculated automatically. The “Results” sheet (see figure) offers a pre-defined summary of the calculation and its results, alerting about remaining stormwater risks.
Replicability: Cost/effort for (new) usage
The Green Factor Tool is easily adaptable to other urban areas, based on the existing Excel sheet.
Materials or other support available
A user manual is available, as well as a guide to modify/adapt the excel sheet. In addition, the website offers information about the tool’s adaptation to Estonia, Finland, Latvia and Sweden.
Website and maintenance
https://www.integratedstormwater.eu/iwatertoolbox
Contact
Riga City Municipality
City Development Department
Nika Kotoviča, e-mail: nika.kotovica@riga.lv
Associated project(s)
Interreg Central Baltic iWater
Step 4 Assessing and selecting adaptation options
Step 5 Implementing adaptation policies and actions
Municipal
The tool is used for new urban development or urban regeneration areas.
Geographical area
All
The toolbox is targeted at landscape architects, architects, urban planners and designers, including those interested in or working with the design, planning or management of urban water.
The user shall be enabled to use Microsoft Excel and shall be able to provide the needed inputs (e.g., rainfall data, green area calculated/estimated).
Disclaimer
The contents and links to third-party items on this Mission webpage are developed by the MIP4Adapt team led by Ricardo, under contract CINEA/2022/OP/0013/SI2.884597 funded by the European Union and do not necessarily reflect those of the European Union, CINEA, or those of the European Environment Agency (EEA) as host of the Climate-ADAPT Platform. Neither the European Union nor CINEA nor the EEA accepts responsibility or liability arising out of or in connection with the information on these pages.
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This translation is generated by eTranslation, a machine translation tool provided by the European Commission.