Data fields: groundwater level

Groundwater level observations made manually with a dipping tape are available. The frequency of observations varies from monthly to once every six months, with significant missing periods across different drillholes depending on the monitoring requirements.

There are three different datums in which groundwater level data is available. This figure shows how they inter-relate:

Automated groundwater level measurements are available for some monitoring wells on the Aquarius Web Portal at Water Data SA. These measurements are not available through Groundwater Data.

Depth to Water (DTW)

This is the depth to water level in metres measured below a reference point. Increasing numbers indicate an increasing depth to water. Negative numbers indicate flowing artesian conditions. The reference point’s true elevation above ground surface can change i.e. if a casing standpipe is installed, removed, or modified, so although this number is the “raw measurement” it should generally not be used for analysis.

Warning

Do not use Depth to Water for analysis.

Standing Water Level (SWL)

This is the Depth to Water, automatically corrected such that it represents a depth below ground level. Increasing numbers indicate an increasing depth to water. Negative numbers indicate flowing artesian conditions. The SWL and DTW values are only different when well elevation data is available and the two elevation values (of the reference point, and the ground) are different - the difference is used to calculate the SWL. If they are the same (e.g. maybe the elevation was derived from a digital elevation model), or no elevation data is available, then the SWL will be present but it will be identical to the DTW.

Note

Use Standing Water Level for all trend or status analysis of data from individual wells.

Reduced Standing Water Level (RSWL)

This value has been corrected to represent the groundwater level measured above Australian Height Datum (AHD). Increasing numbers indicate a decreasing depth to water. RSWL values are only present when we have an elevation survey for that well. This is obviously the correct value to use for most purposes, if it is available.

Note

Use Reduced Standing Water Level for all analysis of data between wells i.e. groundwater flow analysis.

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Fields and field names are listed below for: the CSV file obtainable from Groundwater Data; the JSON returned by GetWaterLevelDetails; and the pandas DataFrame returned by sa_gwdata.water_levels(). A dash indicates the field is missing.

Property	Description	CSV	DataFrame	JSON
Drillhole number	Alternative unique well ID	DHNO	dh_no
Observation well network	Not all wells are part of a network - most are not, in fact.	network	network
Unit number (integer format)	Alternative unique well ID	Unit_Number	unit_long
Aquifer monitored	Aquifer interval(s) opposite the production zone	Aquifer	aquifer
UTM easting		Easting	easting
UTM northing		Northing	northing
UTM zone		Zone	zone
Unit number (hyphenated)	Alternative unique well ID	Unit_No	unit_hyphen
Obswell number	Alternative unique well ID - not assigned for all wells	Obs_No	obs_no
Water level observation date		obs_date	obs_date	OBS_DATE
Depth to water (DTW)	The actual measurement recorded in most cases	dtw	dtw
Standing water level (SWL)	Automatically derived from DTW	swl	swl	STANDING_WATER_LEVEL
Reduced standing water level (RSWL)	Automatically derived from RSWL	rswl	rswl	REDUCED_STANDING_WATER_LEVEL
Pressure		pressure	pressure
Temperature		temperature	temperature
Dry indicator		dry_ind	dry_ind
Anomalous indicator	Y/N indicating anomalous data	anom_ind	anomalous_ind	ANOMALOUS_IND
Pumping indicator	Y/N indicating that pumping was observed locally at the time of measurement	pump_ind	pump_ind	PUMPING_IND
Measured during		measured_during	measured_during	MEASURED_DURING
Data source		data_source	data_source	DATA_SOURCE_CODE
Comments		Comments	comments