Real-Time Water Data and Surface Water Data

Monitoring sites throughout South Australia measure a range of hydrological and meteorological parameters. The range of data available for each monitoring site will vary.

Each site is configured for a specific purpose. Some parameters are region specific and may not be present for sites in all regions.

The following describe principal parameters deployed at monitoring sites throughout South Australia.

Water Quantity

Water quantity available for a site may include:

• Water level: Water level values are measured in metres (m). Surface Water levels are measured by either local datum with an arbitrary value (generally 1.000 or 10.000 metres) representing Cease to Flow or referenced to the Australian Height Datum (AHD). Groundwater data is generally measured as Depth to Water, being the depth from a reference point on the well casing down to the water surface.

• Flow rate: Flow rates are measured in Megalitres per day (Ml/d).

• Storage volume: The Storage Volume of a lake or reservoir may be expressed in two ways: Absolute volume in Gigalitres (Gl); or Proportion (%) of its Full Supply Level (FSL).

Water Quality

The continuously recorded physical and chemical water quality data available is:

• pH: Acidity or alkalinity is measured in pH units.

• Dissolved oxygen: Dissolved Oxygen (DO) is measured in Milligrams per Litres (mg/l) but can also be expressed as a percentage. To convert a reading in mg/l to a percentage, divide by 10,000.

• Salinity: The salinity of a water body is measured by its Electrical Conductivity (EC), which is expressed in microSiemens per centimetre (μS/cm), commonly termed "EC Units". Due to the fact that EC varies with temperature, values are "corrected" to the EC at 25°C.

Salinity is commonly measured as follows:

• Near the surface of a water body, which gives a general indication of the salinity of a water body.

• Near the bed of a water body, which can indicate saline groundwater accessions to a water body.

• In a groundwater bore when the measuring point is considered a reasonable representation of the salinity of the adjacent aquifer.

• Typical Electrical Conductivity Ranges of various water bodies are shown in the table below.

Meteorological

• precipitation (rainfall) measured in millimetres (mm).

• relative humidity as a percentage.

• wind speed measured in kilometres per hour (km/h), as an average over a time period.

• wind direction measured in degrees, as an average over a time period.

Data accuracy

Site data may be biased towards specific requirement(s). For example, a site measuring salinity may be equipped with a sensor that is highly accurate in fresh or brackish conditions, but less accurate in saline or brine conditions. In this case, the data outside of the specific range of interest may not have the same level of accuracy.

The location of a site is often a compromise between accessibility, engineering constraints, environmental sensitivity and technical requirements. Site location factors have a significant influence on data quality.

Other influences include the method used to measure and record the data, damage to recording equipment during extreme weather and equipment calibration changes over time.

Whilst all data undergoes a thorough validation process prior to archiving, this is not the case for telemetered data, which is published in near real-time. Users must be aware of these factors can affect the usability of the data.

More detailed data quality information is available by request, using the Contact Us page. We can assist you in the suitability of data for your purposes.