Water Management
Salinity modelling
Modelling is used to fill information gaps where data is limited or to add value to data by combining it in ways that represent processes that are otherwise not directly mappable. For example, it is not possible to directly map the extent of salinisation in 2050, but by using a model that represents the processes of dryland salinisation, it is possible to extrapolate from existing spatial data to make predictions about future condition.
To manage salinity in a catchment we need to know:
- Where and how much salt is stored in the landscape
- How salt and water moves in the landscape
- How the geology and structure of the landscape contributes to the problem
- What affects the rate of movement of salt
- How changing something in one location affects the rest of the catchment or basin.
Computer based modelling tools also support natural resource management by enabling different management options to be explored and evaluated, or to allow data to be extrapolated in time and space when limited data is available.
Instream salinity models of NSW tributaries in the Murray-Darling Basin
- Volume 1 – Border Rivers Salinity Integrated Quantity and Quality Model (PDF 4 MB)
- Volume 2 – Gwydir River Salinity Integrated Quantity and Quality Model (PDF 2.7 MB)
- Volume 3 – Namoi River Salinity Integrated Quantity and Quality Model (PDF 2.8 MB)
- Volume 4 – Macquarie River Salinity Integrated Quantity and Quality Model (PDF 3.5 MB)
- Volume 5 – Lachlan River Salinity Integrated Quantity and Quality Model (PDF 4.3 MB)
- Volume 6 – Murrumbidgee River Salinity Integrated Quantity and Quality Model (PDF 3.2 MB)
- Volume 7 – Barwon-Darling River Salinity Integrated Quantity and Quality Model (PDF 2.9 MB)
The department monitors river salinity at a number of locations across NSW. The following table shows salinity levels at key river sites over recent years:
Recorded NSW river salinity for selected locations from 2000 to 2003 and 2003 to 2006
| Stream and Measuring Point | Mean daily river salinity levels (EC) for specified period | |||
|---|---|---|---|---|
| * indicates end of valley | Period of record | 2000 to 2003 | 2003–2006# | Maximum @ |
| Murrumbidgee at Balranald* | 1992–2006 | 158 | 135 | 1133 |
| Murrumbidgee at Wagga Wagga | 1993–2006 | 142 | 135 | 521 |
| Lachlan at Booligal* | 1999–2006 | 545 | 723 | 1097 |
| Lachlan at Forbes | 1999–2006 | 472 | 552 | 1170 |
| Barwon–Darling at Collarenebri | 2002–2006 | 345** | 300 | 533 |
| Bogan at Gongolgon* | 2000––2006 | 534 | 425 | 982 |
| Macquarie at Carinda* | 1999–2006 | 559 | 651 | 1207 |
| Macquarie at Baroona | 1999–2006 | 476 | 499 | 989 |
| Castlereagh at Gungalman Bridge * | 2001–2006 | 985** | 531 | 1555 |
| Namoi at Goangara* | 1995–2006 | 495 | 395 | 1165 |
| Namoi at Gunnedah | 1995–2006 | 578 | 534 | 1170 |
| Mehi at Bronte* | 2001–2006 | 505** | 511 | 966 |
| Macintyre at Holdfast | 2002–2006 | 349** | 309 | 575 |
| Hunter at Greta | 1992–2006 | 672 | 690 | 1417 |
Source: DNR 2006.
Note: * indicates end of valley site
** indicates incomplete period of record
# data only available to March 2006
@ maximum spot readings