Title

VAF_EXTENT_108UMTD 

Alternate title

VAF_EXTENT_108UMTD 

Supplemental Information

Related Documents: None 

Status

Completed  

Code

4283 

Maintenance and update frequency

As needed  

Topic category

• Inland waters
• Geoscientific information

Use limitation

General 

Classification

Unclassified  

Statement

Dataset Source: Data were obtained from the Victorian Stratigraphic Database and included: (1) salinity readings from register bores (such as stock and domestic, licensed and observation bores); (2) the date of each salinity reading; (3) bore locations (coordinates). In addition, pre-existing watertable salinity data was obtained from a project conducted by Southern Rural Water. This dataset was used for Catchment Management Areas (CMAs) south of the divide. For the northern portion of the State, bore data were input into the surface modelling utility ANUDEM. To identify the data to be used as input, a point representing the screened interval of the bore was calculated. The established screen location was then compared to the watertable depth compiled as part of the Victorian Watertable Mapping project. Screen locations within 30m of the watertable depth were adopted as watertable bores. Only those bores with salinity readings taken on or after January 1 1980 were used as input. The next step in the process involved creating a series of draft watertable salinity maps using the bore data and contours and visually assessing areas for review. This assessment also involved evaluating the residual values or difference between the modelled surface and the original bore inputs. All residuals greater than 250 were identified and resolved. The resultant model was then merged with the SRW data. A final dataset containing Total Dissolved Solids (TDS) concentrations in mg/L was then produced using the following classes: <500, 500-1000, 1000-3500, 3500-7000, 7000-13000,13000-35000, >35000. Dataset Originality: Derived 

Classification

Unclassified  

Attribute Quality

Comments

Attribute values are as accurate as the attributes of the source data used to derive the final dataset. 

Positional Accuracy

Comments

The dataset is as accurate as the data from which it has been derived. These source datasets include: (1) the SRW watertable salinity layer; (2) the Victorian Stratigraphic Database; (3) borehole locations from GMS. 

Conceptual Consistency

Comments

Not known 

Missing Data

Comments

Victoria 

Excess Data