Rain Garden Selection Tool
The Rain Garden Selection Tool, developed by the experts at RetencjaPL, enables users to quickly assess the potential for managing stormwater through the implementation of rain gardens. The tool helps identify the solution best suited to the site’s soil and groundwater conditions, available space, and catchment characteristics.
In just a few simple steps, users can determine whether a rain garden is suitable for a given location and select the most appropriate solution from the following options:
- Container rain garden
- Rain garden in permeable soil
- Rain garden in impermeable soil
The analysis considers key design parameters, including soil infiltration capacity, groundwater level, site constraints, and local rainfall conditions. Based on these inputs, the tool provides a recommendation that supports sustainable stormwater management and the design of blue-green infrastructure.
The application is available in Poland.
Rain Garden Design Parameters
After selecting the preferred solution, users proceed to the rain garden sizing stage. For each rain garden type, the tool provides a construction diagram illustrating the system layout, operating principle, layer configuration, and the inflow and outflow of stormwater.
Depending on the selected solution, users can define parameters such as:
- catchment area,
- available rain garden area,
- water ponding depth,
- filter and drainage layer properties,
- native soil characteristics,
- drainage or infiltration conditions,
- design rainfall parameters based on the rainfall model.
Based on these inputs, the tool determines the required technical parameters of the rain garden and provides practical guidance on its location, design, and operation.
Rain Garden Design Results
After completing the calculations, users receive a recommended solution together with the key technical parameters, including:
- required rain garden area,
- retention volume,
- stormwater inflow for the selected design rainfall event,
- infiltration rate or controlled outflow,
- utilisation of the available installation area,
- facility drawdown time.
The results are complemented by design recommendations aimed at improving the performance of the rain garden, optimising its size, and ensuring appropriate management of excess stormwater.
In addition, users have access to:
- examples of completed rain garden projects,
- a list of recommended plant species,
- a PDF report summarising the calculations,
- a contact form enabling consultation of the results with RetencjaPL experts.
The generated report can serve as supporting documentation during the investment planning phase and when preparing project documentation related to stormwater management, retention, and blue-green infrastructure.
