Do-it-yourself rapid soil test

The builder can use the following quick soil test to roughly assess whether the building ground is basically suitable for rainwater infiltration:

1. dig a pit measuring 50 x 50 x 50 cm with a spade. The ground should be level.

2. cover the floor with 1 - 2 cm of gravel or chippings and attach a folding rule to a stick driven into the floor.

3. water the pit for approx. 30 minutes to moisten the soil. The pit must be completely emptied before starting the experiment.

4 Fill the pit to approx. 20 cm with water, note the time and water level.
5. Check the water level after 30 minutes. If it has sunk less than 2 cm, check again after 120 minutes.
6. carry out the test a second time. If there are deviations from the first test, a third run is necessary.

• 0 - 2 cm infiltration depth: very low soil permeability (clay/silt)
• 2 - 16 cm infiltration height: low soil permeability (fine sand)
• > 16 cm infiltration height: medium soil permeability (medium sand)
• 20 cm in < 3 min: good soil permeability (gravel)

• < 4 cm infiltration height: insufficient soil permeability (no infiltration possible)
• 4 - 8 cm infiltration height: very low soil permeability (clay/silt)
• > 8 cm infiltration height: low soil permeability (fine sand)