Feature layer depicting the location of boreholes observing groundwater level in shallow and deep aquifers. Currently, most of the measuring objects are equipped with automatic stations that record locally or transmit the data. These stations record once a day. Originally, the boreholes were observed by volunteers with a weekly frequency of measurement. Most of new measuring objects were built during the so-called ISPA project. They went into operation in 2007. The data are stored in the Central Regime Database of Groundwater which is maintained by the Hydrology Database and Water Budget Department.