Hydrogeological Groundwater Units (HGU) are based on, within the water control districts (WCD), 1:250K surface geology mapping of the Northern Territory, except for separately mapped palaeovalleys ﾿ no units added which don﾿t outcrop and quaternary sediments in place. Outside of the WCD area's HGU mapping based on Geological Units: NT 1:2.5 million surface geology except for separately mapped palaeovalleys ﾿ no units added which don﾿t outcrop. Quaternary sediments have been stripped off. Units that don﾿t outcrop in the NT have been added to the HGU geodatabase list. HGU Naming Within WCD HGU naming, in the first instance, is based on managed geological units in water allocation plans (WAP) in the WCD. The remaining units are lumped into geological units with simular hydrological characteristics. HGU Naming Outside WCD HGU Naming based on geological province, lithology class, undifferentiated. Geodatabase Schema provided by the Bureau Of Meteorology (BOM). Bore information was mainly sourced from the Northern Territory Government database Hydstra and populated into the Schema. Other sources of information such as records of all licensed bores from the Water Management Division were used to determine bore status and feature types. Reference to technical reports, bore completions records, driller﾿s logs, and field data such as gamma logs were made to complete stratigraphic bore interpretations. Interpretations were undertaken by: Natural Resources, Environment, the Arts & Sports (NRETAS) Sinclair Knights Mertzs (SKM) Queensland University of Technology (QUT)