Pressures on Surface Water Quality
- Land use impacts within the Murray Darling Basin including areas within other States
- Nutrient loading from diffuse and point sources
- Soil erosion
- Soil salinisation
- Dry climate, intermittent flows and natural salt stores in landscape
Main findings: Location of Water Quality problems and trends
As basin water quality monitoring coverage within Sth Aust was generally too limited to enable basin scale assessments some findings refer to individual monitoring station results.
In terms of number of basins recording site exceedances, salinity was the most wide spread water quality issue in Sth Aust followed by nutrients (both total nitrogen and total phosphorus) and turbidity. To some extent these findings reflect natural conditions within Sth Austn waterways including intermittent flows, a dry climate and naturally high salinity levels in groundwater. Major or significant basin salinity exceedances were recorded for the Mallee (Murray River stations), Myponga, Fleurieu River basin and Willochra Creek although the later is naturally saline. Site exceedances were also recorded within the Broughton, Gawler, Torrens, Onkaparinga, Millicent Coast and lower Murray basins. Although the Lower Murray River Basin did not exceed salinity guidelines at a basin scale it did have a number of highly salinised tributaries. Limited trend data generally indicated no salinity trends except for the Mallee and Lower Murray Basins, which had decreasing trends at Murray River sites for the monitored period.
River basins that recorded significant or major exceedances of total nitrogen included the Lower Murray, Myponga, Fleurieu Peninsula and Willochra Creek. Site exceedances were also recorded within the Broughton, Gawler, Millicent Coast, Coopers Creek and Torrens River basins, the later recording the highest median total nitrogen concentration for any SA site. Limited trend data generally indicated no trends for total nitrogen except for the Torrens and Millicent Coast basins, both which had sites with decreasing trends. However, as the Torrens system receives water transfers from the Murray River, trend patterns are confounded by pumping rates and demand for consumptive use.
Exceedance of total phosphorus guidelines were also wide spread with major and significant basin exceedances recorded for Lower Murray, Myponga, Fleurieu Peninsula and Mallee River basins. Site exceedances were also recorded within the Broughton, Millicent Coast, Coopers Creek and Torrens River basins. Trend analyses indicated no trends for total phosphorus.
Major or significant basin exceedances for turbidity were recorded for the Mallee, Lower Murray and Fleurieu Peninsula River basins. Site exceedances were also recorded within the Broughton, Millicent Coast, Torrens River and Coopers Creek basins, the latter recording the highest median turbidity values. Limited trend data generally indicated no trends for turbidity except for the Mallee and Lower Murray basins both which had Murray River sites with increasing trends. There was an apparent relationship between sites with phosphorus and turbidity exceedances, highlighting that a significant proportion of the phosphorus load in the water column was attached to soil particles
An NLWRA consultant has compiled the Sth Austn summary presented within this section. A State project report is not available for Sth Aust. For further information see the Sth Austn Environment Protection Agency web site or the Sth Austn Department of Water Resources web site. A summary document on water quality in Sth Austn can be viewed at www.dwr.sa.gov.au/publications.pdfs/vol2.pdf
- Department of Environment, Heritage and Aboriginal Affairs (DEHAA)
- South Australian Environment Protection Authority (EPA)
- State established guidelines based on ANZECC (1992) guidelines for protection of aquatic ecosystems
- NHMRC (1996) drinking water guidelines
Routine (regular time period) monitoring (see detailed methodology report).
An Audit consultant has compiled the South Australian summary presented within this section. A State project report is not available for South Australia. For further information see the South Australian Environment Protection Agency web site or the South Australian Department of Water Resources
The following table lists the coverage of water quality monitoring in South Australia. Basins that had no stations used in this assessment of water quality monitoring are not listed in this table.
|Drainage Basin||Number of stations used in water quality reporting||Number of attributes for which exceedance analyses could be determined||Number of attributes for which trend analyses could be determined|
|Lower Murray River||9||5||5|
Click on the basin name in the table to view a water quality report for that basin.
Monitoring coverage for the State is restricted to the more populated and developed areas within the South-East Coast, Murray-Darling and South-Australian Gulf Drainage Divisions. Exceedance analyses were possible for five variables: salinity, turbidity total nitrogen, total phosphorus and pH for a limited number of sites in all monitored basins. Trend analyses were possible for all variables for a limited number of sites in most basins. Monitoring station density and resultant basin coverage was too low to characterise water quality within most South-Australian Gulf and South-East Coast Drainage Division basins.
Not all available State data was included in analysis due to limitations in terms of period of record and frequency of collection.
An Audit consultant has compiled the South Australian summary presented within this section. A State project report is not available for South Australia.
Application of findings
Monitoring of the Murray River in South Australia provides an important indication of the health of the whole Murray-Darling River basin and the management responses required both within South Australia and other upstream States. The high turbidity and associated high concentrations of total phosphorus observed in the South Australian reach of the Murray point to the need to better manage soil erosion within the basin. It also indicates the importance of managing the mix of Murray and Darling River water within the context of South Australia's entitlement flows.
The measurement of conductivity is also important for identifying where management responses are required to reduce salt loads affecting the water resources of the Lower Murray basin which supplies up to 40% of Adelaide and its environs potable water requirements.
The highly eutrophic conditions observed for the Torrens River, including both high total nitrogen and phosphorus concentrations, highlights the problems associated with diffuse source pollutants and provides support for the South Australian Government and Catchment Water Management Board program to reduce stormwater pollution within this basin.
There is only limited information on the water quality of many inland waterways with most available data for the Lower Murray River and waterways in and around the Adelaide metropolitan area. Although it is recognised that most waterways in South Australia are intermittent and therefore difficult to monitor, this information is considered important as catchment modification and agriculture is wide spread throughout the southern section of the State.
There is also no water quality information on ecologically important waterways such as Lake Eyre and Torrens.
Based on the water quality assessments undertaken the following recommendations are made:
- The current monitoring program in the Murray River be maintained to ensure that any changes in water quality are detected;
- Monitoring of tributaries of the Murray River be maintained and possibly expanded to assess the continuing contribution of salt loads to the Murray-Darling River system;
- The collection of baseline water quality data in other waterways be considered especially in ephemeral waterbodies such as Lake Eyre
- Remedial actions and the continued monitoring of Torrens River be continued; and
- An assessment of catchment activities on salt loads in selected catchments be undertaken
- Further information can be obtain from:
- Link to Map Maker.
Links to an another web site
Opens a pop-up window