Phreatic Standing Water Level Contours at 10m Intervals - ARC

## **Abstract** \n\nThis dataset and its metadata statement were supplied to the Bioregional Assessment Programme by a third party and are presented here as originally supplied.\n\nPoints at 10m intervals of the SWL depths to the phreatic groundwater zone.\n\n## **Purpose** \n\nTo represent SWL depths to the phreatic groundwater zone at 10m intervals.\n\n## **Dataset History** \n\nAll drillholes with recorded construction information, water cut and static water level (SWL) information within the study area were extracted from the South Australian Government Geological database SAGeodata.\n\nAs a first pass, the first water cut was compared to the SWL if the SWL was lower than the first water cut, the SWL was accepted. If the SWL was more elevated than the first water cut, further analysis was undertaken.\n\nFurther analysis involved reviewing the construction details of the well. If either a) the top of the well screen was more elevated than the SWL, b) the well screen included the first water cut or c) the well was open, the SWL was accepted as phreatic. However, if a) the well was artesian b) the screen did not cover the first water cut interval or b) no construction information was available, the well was rejected.\n\nFinally, in order to both ensure adequate well coverage and to limit the amount of work undertaken, phreatic surfaces that included SWL that appeared slightly sub artesian were calculated and compared. In areas of adequate well coverage, minimal difference was not between wells where there was a 1, 5 and 10m sub-artesian difference between the first water cut and the SWL. Consequently, a margin of error of +10m was allowed for wells with SWLs more elevated than the recorded water cut.\n\n## **Dataset Citation** \n\nSA Department of Environment, Water and Natural Resources (2015) Phreatic Standing Water Level Contours at 10m Intervals - ARC. Bioregional Assessment Source Dataset. Viewed 26 May 2016, http://data.bioregionalassessments.gov.au/dataset/5abaeb6a-fa54-48c9-bc92-41bb4ac12fcf.