Drinking water wells have to be constructed according to the Austrian water act and the legislation concerning water supply.
A drinking water well has to be covered impermeably and to protrude at least 30 cm from the soil.
On the well cover a ventilation has to be installed. On the inside a fly screen has to be attached.
This is necessary, so that flies, worms and other pests are prevented from intruding into the well.
If a fly screen is missing, toxic germs can be inserted into the well.