State of the Environment Report title
2 0 0 4

2004 Report



Tumbarumba

Surface water quality

Indicator description

Results for this indicator are also available for  

What the results tell us for Tumbarumba

| Water quality graphs | Data summary | Trends |

Most rivers in Tumbarumba Shire are part of the upper Murray River catchment, with some in the Murrumbidgee River catchment. No surface water quality data were available for rivers in the Murrumbidgee catchment. The quality of surface waters in the upper Murray River catchment continued to be poor in the current reporting period in relation to three water quality parameters, although it had improved for these and some other parameters compared with the previous period.

This assessment was based on the results for a variety of physico-chemical parameters at seven monitoring sites in the upper Murray River catchment (see Interpreting the data). The results showed that the median values for total nitrogen, total oxidised nitrogen and total phosphorus exceeded the default trigger values during the current period at all five sites for which data were available. The median values were 2.5–3 times the trigger value at two sites for total nitrogen, 2–22 times the trigger value for total oxidised nitrogen at four sites, and 2–4 times the median value for total phosphorus at all five sites. Although all exceedences for these parameters were smaller in magnitude than for the previous reporting period, they remain a warning for land managers to prioritise action to improve surface water quality for rivers in the shire.

The main environmental value for most water bodies in Tumbarumba Shire was the protection of aquatic ecosystems. These ecosystems sustain a diverse range of plants and animals and provide a focus for water-based recreational activities and eco-tourism. Water from the shire's rivers also sustains much of the area's irrigated agriculture.

Trends in surface water quality

| Graphs | Data table |

The seven monitoring site in the shire which data were available are:

All sites were classified as upland streams.

Water quality at each site was assessed by comparing the median values of parameters for the reporting period with the appropriate default trigger values . This approach acts as a warning system to alert natural resource managers of when management changes may be needed. Where individual parameter values exceeded the default trigger values at the time of monitoring, this did not necessarily change the median value sufficiently to trigger a management warning.

Limited data were available for the current reporting period for two monitoring sites (Tooma River at Warbrook; Tumbarumba Creek at Tooma, MacGinnity Bridge) and comparable data for both reporting periods were available for only four sites (see Table 1).

The default trigger values for total nitrogen, total oxidised nitrogen and total phosphorus were exceeded, often substantially, at five of the seven monitoring sites (Tumbarumba Creek at Tumbarumba, Mannus Creek at Tooma, Maragle Creek at Maragle, Jingellic Creek at Jingellic and Murray River at Indi Bridge) during the current reporting period (see Table 1). These results are a serious warning to alert natural resource managers to take action to improve water quality at the sites, especially for total nitrogen at Mannus Creek and Jingellic Creek, total oxidised nitrogen at Jingellic Creek, Mannus Creek and Tumbarumba Creek, and total phosphorus at Tumbarumba Creek, as the median values were from 2.5 to 22 times higher than the default values at these sites.

The median values for total dissolved solids were relatively high (45–95 mg/L) during the current reporting period at all six sites for which these data were collected, and were highest at Manus Creek and Jingellic Creek (see Table 1). The median value for total suspended solids was highest at the Murray River at Indi Bridge site (32 mg/L; see Table 1).

Despite the above exceedences for total nitrogen, total oxidised nitrogen and total phosphorus, the median values for these parameters had improved (often substantially) compared with the previous reporting period. Water quality at some monitoring sites had also improved during the current period compared with the previous period for other parameters (e.g. pH, turbidity; see Table 1).

Table 1. Water quality at Tumbarumba Shire monitoring sites, 1997 to 2004
Parameter* and locationMedian valuesDefault trigger
values**
1997–20002000–04
Tooma River at Warbrook (site 401003) view graph
Total dissolved solids (mg/L)-50
Total suspended solids (mg/L)-12
Dissolved oxygen (mg/L)15-
Electrical conductivity (µS/cm)70-350
pH7.9-Lower limit 6.5
Upper limit 7.5
Temperature (degrees C)30-
Total nitrogen (µg/L)500-250
Total oxidised nitrogen (µg/L)110-15
Total phosphorus (µg/L)50-20
Turbidity (NTU)26-25
Tumbarumba Creek at Tumbarumba (site 401007) view graph
Dissolved oxygen (mg/L)1110
Electrical conductivity (µS/cm)4835350
pH7.67Lower limit 6.5
Upper limit 7.5
Temperature (degrees C)2010
Total nitrogen (µg/L)470255250
Total oxidised nitrogen (µg/L)1008015
Total phosphorus (µg/L)1005815
Total suspended solids (mg/L)-9
Turbidity (NTU)641220
Mannus Creek at Tooma (site 401008) view graph
Dissolved oxygen (mg/L)1510
Electrical conductivity (µS/cm)125107350
Nitrate as N-0.2
pH8.37.4Lower limit 6.5
Upper limit 7.5
Temperature (degrees C)3017
Total dissolved solids (mg/L)-84
Total nitrogen (µg/L)800620250
Total oxidised nitrogen (µg/L)3409015
Total phosphorus (µg/L)403820
Total suspended solids (mg/L)-14
Turbidity (NTU)311120
Maragle Creek at Maragle (site 401009) view graph
Dissolved oxygen (mg/L)1310
Electrical conductivity (µS/cm)17985350
Nitrate as N-0.2
pH8.37.5Lower limit 6.5
Upper limit 7.5
Temperature (degrees C)2514
Total dissolved solids (mg/L)-70
Total nitrogen (µg/L)850300250
Total oxidised nitrogen (µg/L)1502015
Total phosphorus (µg/L)653720
Total suspended solids (mg/L)-5
Turbidity (NTU)42920
Jingellic Creek at Jingellic (site 401013) view graph
Dissolved organic carbon (mg/L)-5
Dissolved oxygen (mg/L)1710
Electrical conductivity (µS/cm)135120350
Nitrate as N-0.4
pH8.17.4Lower limit 6.5
Upper limit 7.5
Temperature (degrees C)3020
Total dissolved solids (mg/L)-95
Total nitrogen (µg/L)1150765250
Total organic carbon (mg/L)-5
Total oxidised nitrogen (µg/L)630>33015
Total phosphorus (µg/L)1054220
Total suspended solids (mg/L)-15
Turbidity (NTU)1121525
Tumbarumba Creek at Tooma, MacGinnity Bridge (site 40110001) view graph
Dissolved oxygen (mg/L)15-
Electrical conductivity (µS/cm)51-350
pH8-Lower limit 6.5
Upper limit 7.5
Temperature (degrees C)26-
Total nitrogen (µg/L)500-250
Total oxidised nitrogen (µg/L)60-15
Total phosphorus (µg/L)80-15
Turbidity (NTU)60-20
Total dissolved solids (mg/L)-46
Total suspended solids (mg/L)-8
Murray River at Indi Bridge (site 401556) view graph
Dissolved organic carbon (mg/L)-2
Dissolved oxygen (mg/L)-10
Electrical conductivity (µS/cm)-51350
Nitrate as N-0.2
pH-7.3Lower limit 6.5
Upper limit 7.5
Temperature (degrees C)-16
Total dissolved solids (mg/L)-45
Total nitrogen (µg/L)-330250
Total organic carbon (mg/L)-3
Total oxidised nitrogen (µg/L)-30<15
Total phosphorus (µg/L)-4020
Total suspended solids (mg/L)-32
Turbidity (NTU)-925

* µS/cm = microsiemens per centimetre; µg/L = microgram per litre; NTU = nephelometric turbidity unit; mg/L = milligram per litre; ** For information on default trigger values, see Interpreting the data; – = no data; = exceedence of the default trigger value

About the data

The water quality sites covered in this report were monitored by the NSW Department of Infrastructure Planning and Natural Resources (DIPNR), which is also responsible for quality control and on-going maintenance of the data collected in their databases http://waterinfo.nsw.gov.au/wq/sitelist.html.

Interpreting the data

Default environmental value
The Water Quality and River Flow Interim Environmental Objectives (EPA 1999) for NSW, which are still current, indicate that protection of aquatic ecosystems is the default environmental value for most water bodies in the Murrumbidgee catchment (in which the shire is mostly located). Although individual councils are free to assign additional or different value through local processes and based on site-specific information, so far no councils in the Australian Capital Region have done so.
Default trigger values
The default trigger values used in this report were those values set out in ANZECC and ARMCANZ (2000). The values applicable to the Australian Capital Region are those for 'south-east Australia for slightly disturbed ecosystems' (ANZECC and ARMCANZ 2000). The default trigger values for different water quality parameters for the protection of aquatic ecosystems are based on the type of water body in question. Compared to most other environmental objectives, the protection of aquatic ecosystems is one that requires more stringent water quality guidelines.
Type of waterbody
For the purposes of this State of the Environment Report, an appropriate waterbody type—lowland coastal rivers below 150 metres altitude or upland streams above 150 metres altitude—was assigned to each monitoring site in the shire.

The median value (i.e. middle value of a data series) for each monitoring site in the shire over the reporting period was compared with the default trigger value from the guideline values suggested in ANZECC and ARMCANZ (2000). This approach was recommended when no environmental values were set, water quality objectives were not determined, local reference sites were unavailable and local site-specific information could not be sourced. This broad reporting approach cannot be used to assess 'compliance'; it is merely a warning system to alert natural resource managers.

Additional data

Other potential sources of water quality monitoring data include the Community Access to Natural Resources Information (CANRI) website and the Waterwatch program. A search of Waterwatch Australia's web-based database in July 2005 did not provide any surface water quality data relevant to Tumbarumba Shire.

References

ANZECC and ARMCANZ (2000) Australian and New Zealand Guidelines for Fresh and Marine Water Quality, National Water Quality Management Strategy No. 4, Australian and New Zealand Environment and Conservation Council and the Agriculture and Resource Management Council of Australia and New Zealand, October 2000.

Environmental Protection Authority (NSW) (1999) Water Quality and River Flow Interim Environmental Objectives: Murrumbidgee River and Lake George, NSW Environment Protection Authority, Sydney, on-line at http://www.epa.nsw.gov.au/ieo/Murrumbidgee/index.htm.

EPA—see Environmental Protection Authority (NSW)