With this design tool it is possible to carry out introductory calculations on your application in which the hard surfaces interact with storm water designs. The knowledge developed within the Vinnova financed projects “Grey green system solutions for sustainable cities” and “Climate secured system solutions for urban areas” has been integrated in the design tool.
The tool is intended to be used for introductory calculations before detailed planning is started, which means that it has some limitations. There are also some features missing due to restrictions in budget and time within the projects. Here are some bullets on limitations and identified needs for improvements:
- An interface in Swedish needs to be created.
- The input data set cannot be saved.
- Help menus in conjunction to the fields to be filled in needs to be added. Among others the default values on pore volumes and hydraulic conductivities should be shown.
- The current included pavements the design tool has to be completed with the possibility to choose from more types of surface courses.
- No water flow from surrounding areas is taken into account. Only the rain that over the areas over the application is taken into account.
- Only 10-year rain fall with a climate factor of 1.25 is implemented. The intensities and durations are according to Dahlström (2010).
- The maximum surface of the pavement is limited to 10 000 m2.
- The effect of subsequent rain falls is not taken into account, i.e. it is assumed that the no storm water is contained in the system when a rain fall starts.
- Only horizontal areas are considered.
- For non-permeable pavement with storm water retention capacity it is possible to temporary store storm water in the sub base layer. No flow calculations evacuating the water through draining pipes and the subgrade or inflow from any storm water construction are included in the current version of the design tool. Only the available storage volume in the sub base layer is considered.
Research Institutes of Sweden
Urban Water Management
Tel: +46(0)10 516 50 00, (direct) +46 (0)10 516 63 35