A tool for sizing infiltration components

Infiltration volume estimation

The Infiltration volume estimation tool calculates the depth of storage required and the drain-down time to half empty for soakaways based on information on their plan area dimensions, fill porosity and infiltration rate. Various soakaway arrangements can be analysed. The tool applies the method defined originally in the report Infiltration Drainage (CIRIA report R156, 1996), which is re-stated in the SuDS Manual C753.

When to use this tool?

The Infiltration volume estimation tool enables the user to size soakaways where runoff from paved surfaces is to be infiltrated

How to use the tool?

The tool is available as an excel spreadsheet, which all registered users can download and saved locally for free. Once saved locally, the tool is only valid for 19 days. After that, you will need to download the spreadsheet again from this website.

Important note
The spreadsheet does not work on a Mac. To the best of our knowledge the spreadsheet also does not work in Excel 2016. However it does work in Excel 2010 (and earlier versions) and in Excel 365. When you open the spreadsheet it will ask you to ‘Enable Editing’ and ‘Enable Content’ before you can use it. You do not need a password to use the spreadsheet. 

What values will the tool give?

For a given geometry of a soakaway, a porosity value and infiltration rate, the tool gives you the minimum required depth for the soakaway and the time it takes to half empty. 
User can save and compare the results obtained.  





HR Wallingford provides training in the use of UK SuDS tools, plus planning and design of SuDS to meet current standards and best practice. 

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