home > Services > calculations/standards > Attenuation tank sizing

The required capacity for attenuation tanks depends on a number of factors which are unique to each project. We can
model the circumstances on a project using Microdrain software to calculate the volume of water storage required.
To undertake this exercise, we need the following information:

1. Impermeable drained area, i.e. roads,
   car parks, roofs
2. Maximum rate of discharge permitted
   from the site
3. Storm return period, now typically
   1 in 100 years
4. Geographical location
5. Approx depth of drainage system
6. Plan area where attenuation needs
   to be located