Water conservation districts and zones and the location of wells and well galleries are demarcated following the large-scale maps Berlin Public Water Companies and the Berlin Department of Urban Development and Environmental Protection. Amounts withdrawn by waterworks wells or well galleries are set by the public water companies. The location and removal amounts of private sector water supply plants for West Berlin are taken from the corresponding data base of the Arbeitsgruppe Wasserwirtschaftliche Grundlagen (Work Group Water Management Standards) of the Berlin Department of Urban Development and Environmental Protection. East Berlin data was taken from a provisional regional committee list made by a GDR Institute for Water Management.
The delineation of protection areas and the removal amounts of the Brandenburg Waterworks was made available by the water supply operators themselves.
The data for withdrawal volumes of private sector water supply plants and the waterworks or well galleries in West Berlin are based on the water economy year (November – October). All other figures are based on the calendar year. Figures for Berlin Public Water Companies plants are from 1990; those of the private sector water supply plants and of the Brandenburg Waterworks are from 1989.