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Kirstin Miller 3151044 Using physio-chemical parameters and biological indicator species to assess the water quality at Tillegra Bridge, Bandon Grove and Alison Rd overpass along the Williams River, NSW. This report was undertaken in the Williams River catchment area in the Hunter region, NSW and discusses the use of physio-chemical parameters and biological indicator species in assessing the condition of sites along the Williams River( Appendix a). Originating in the pristine Barrington Plateau, with an elevation of approximately 1500m ASL, the Williams and Chichester rivers catchments cover a combined total of 1173km² and are part of the wider Hunter Water catchment which supplies the drinking water for the lower Hunter regions. Draining the southern slopes of the world heritage listed Barrington Tops National Park the Williams River travels 140km and is fed by ten creeks and rivers, before it unites with the Hunter River decreasing in elevation by 750m over this distance. The land in the headwaters is pristine National park and forestry with the influence of extensive cattle farming and irrigation demands increasing further downstream on the river flats. The river receives input from ten creeks and rivers including the Chichester, a major tributary. The Chichester River drains the eastern slopes of the Barrington Tops NP and is impounded forming the 18,356 ML Chichester dam. The 199km² catchment is 76% national park (HWC 2011a). Although only 20km in length the Wangat River is a major tributary to the Chichester. Elevation decreases by 900 m over the short distance. The entire catchment area of the Wangat is located in the pristine rainforests and alpine environment of Barrington Tops NP and flows directly into the dam. The Chichester and Wangat catchments are of the most pure catchments within Australia with large remote areas unaffected by human influence. There is high runoff due to high precipitation averages and therefore the dam fills quickly after periods of rain. Chichester Dam was the regions first drinking water storage site replacing the outdated water works at Maitland, and today supplies around 35% of water to the lower Hunter (HWC, 2011b). Water is treated with chlorine at the dam then as a benefit of the elevation of the impoundment, water is gravity fed almost 80km for further treatment at Dungog Water Treatment Plant. Average environmental flows of 14 ML/day and 30 ML/day during peak periods are released to maintain ecological integrity downstream of the impoundment. The Chichester River drops rapidly in elevation by 1240m along the 42km course from headwaters before its confluence with the Williams at Bandon Grove (HWC, 2011b). The Williams passes through the towns of Dungog and Clarence Town, both of which have small waste water treatment facilities. The Williams is free flowing until reaching Mill Dam Falls, 18km before its confluence with the Hunter River at Raymond Terrace. Flow is disrupted by the Seaham weir to create a weir pool which acts as a barrier, limiting the movement of tidal waters upstream. The water from here is conveyed (canal and pumped) to Grahamstown Dam, an off river storage facility (HWC, 2011c). Grahamstown Dam is the Hunters largest drinking water storage dam, 1

Kirstin Miller 3151044 holding up to 182,305ML. The Williams River is responsible for 50% of Grahamstown dam inflow. Therefore the monitoring of the water quality of the Williams River is important so as any biological degradation can be addressed accordingly. This study aims to assess the water quality of three sites along the Williams River using biological indicator organisms for rapid assessment and selected physio-chemical parameters. Study sites Tillegra Bridge, Sailbury Rd, Munni. This site was the furthest upstream sample site of this study. The adjoining land use of the left bank is unfenced pastoral land whist the right bank of the site it was moderate density of isolated vegetation approximately 10Ha. Left riparian zone was of semicontinuous vegetation which is highly eroded, allowing stock access to the sample site. Using Google Earth for assessment of upstream, erosion was not as severe as at the site. Visual water and sediment quality and characteristics at this site were all normal/none. Water level was at base flow and visually assessed as clear. Less than 5% debris was present in one location on the edges of the left bank riparian zone. No unnatural alteration to the flow at this site was evident. Main factors influencing this site were cattle effluent and bank erosion. Chichester Dam Rd, Bandon Grove The sample site at Bandon Grove is 200m after the Chichester meets the Williams and approximately 4km downstream from the sample site at Tillegra Bridge. A weir is present with a rock ramp fishway to accommodate migrating fish species. Chichester Dam Rd passes over the site via a high bridge with large concrete supports built into the river bed. All samples were collected downstream of the fishway. There was a continuous riparian zone on both sides from the confluence of the Chichester and the Williams to Bandon Grove. There is high erosion on the Williams just upstream from the confluence; the Chichester however has very limited erosion and continuous riparian zone. The site is adjacent to a picnic/overnight camping ground which has direct access to the river via several scattered tracks for recreational activities. Water level was at base flow and visually assessed as clear. Alison Rd, Alison The Alison Rd sample site is downstream from the towns of Dungog and Clarence Town. The riparian zone on both sides was the most dense and most continuous of all sample sites. Light penetration to the site was hindered due to the density of foliage cover. There is no evidence of bank erosion or stock access; however there is evidence of human use for recreational activities such as fishing or kayaking. Surrounding land use is primarily agricultural; more intense on the left. There was a large stump caught under the bridge which may be from the last flood. Water level was at base flow and visually assessed as slightly turbid with suspended and dissolved materials.

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Kirstin Miller 3151044

Investigations will be made as to whether i) Nitrate and Orthophosphate levels increase further downstream due to influencing factors such as cattle access to the river and human activities. ii)Dissolved Oxygen decreases the further downstream and if so does this influence macro invertebrate assemblages. iii)Turbidity is higher downstream due to influence of suspended and dissolved particulate matter. Results The results for the three selected water quality variables have mean plotted with standard error of the means. Nutrients There have been significant differences in nutrient levels identified in this data. The nitrate level at Bandon grove was the lowest at 0.205 mg/L., around half the average concentration recorded at Tillegra and Alison Rd. Bandon Grove also returned the lowest standard error which suggests this sample was closest representation of the true nitrate level of all sites. Taking in to account the high standard error associated with each site average orthophosphate levels were fairly evenly distributed between sites. There is no significant difference in Nitrate and Orthophosphate levels on a spatial scale between sites (Figure 1).

0.5 0.45 0.4 0.35

m g/L

0.3 0.25 0.2 0.15 0.1 0.05 0 Tillegra Bridge

Bandon Grove

Alison Road

Figure 1: Mean (+/- SE, n=16) Nitrate and Orthophospate concentrations (mg/L) of the sample sites along the Williams River, NSW.

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Kirstin Miller 3151044 However temporal variations were apparent within the sites. Orthophosphate levels were significantly different between sample days at Bandon Grove and Alison Rd. The highest levels of Orthophosphate at these sites were both recorded on the 18/8 (Fig 2).

0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 Figure:2. Mean (+/- SE. n=8) Nitrate and Othophosphate concentrations (mg/L) of the sample days and sites along the Williams River, NSW.

Turbidity Turbidity has been identified as having spatial differences. There are significant differences in turbidity between all sample sites. Alison Rd the furthest downstream point of sample had the highest average NTU with a high variation of replicate sample values. The lowest average NTU was at Bandon Grove supported by small standard error (Fig 3).

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Kirstin Miller 3151044

14 12 10

NTU

8 6 4 2 0 Tillegra Bridge

Bandon Grove

Alison Rd

Figure 3: Mean (+/- SE, n=16) Turbidity (NTU) of the sample sites along the Williams River, NSW.

Turbidity was significantly different between sample days at Bandon Grove and at Alison Rd. Sampling on the 17/8 at Alison Rd showed the highest average NTU and the highest mean of 21.28 NTU. The remaining sites ranged from 1.01 NTU to 7.08 NTU. Turbidity at all sites was greater on the 17/8 (Fig 4). 25

20

NTU

15 10 5

0 Figure4: Mean (+/- SE, n=8) Turbidity (NTU) of the sample days and sites along the Williams River, NSW.

Dissolved Oxygen (DO) There are significant differences in the Dissolved Oxygen content of the sample sites. DO was highest at the most upstream point of sample and decreased in concentration the further downstream sampled. DO decreased by 0.6mg/L between Tillegra and Alison Rd (Fig 5).

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Kirstin Miller 3151044

10.2 10

mg/L

9.8 9.6 9.4 9.2 9 Tillegra Bridge

Bandon Grove

Alison Rd

Figure 5: Mean (+/- SE, n=16) Dissolved Oxygen concentrations (mg/L) of the sample sites along the Williams River, NSW.

All site showed temporal and spatial variation in DO. The greatest mean difference between days was at Alison Rd. Tillegra had the most consistent concentration across both days. Average DO levels were lower on the 18/8 at all sites (Fig 6). 10 9 8 7 mg/L

6 5 4 3 2 1 0 Figure 6: Mean (+/- SE, n=8) Dissolved Oxygen concentrations (mg/L) of sample days and sites along the Williams River, NSW.

Macro invertebrates Macro invertebrate and associated data was combined over the two days. Using macro invertebrates collected at the sample sites the Stream Comparison Index, Stream Pollution Index and the # of taxa has been calculated to determine the condition of these sites and give an indication to the health of the Williams River. This study followed the methods outlined by Chessman (2003) in the SIGNAL2.iv Users Guide. However instead of the recommended 100 organisms required for calculating SCI, only 75 organisms per sample were used. The SCI has been averaged by 16 samples per site and is representative of the 2 sample days combined to as there was little difference in macro invertebrate

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Kirstin Miller 3151044 assemblages between days. Tillegra Bridge had the highest pollution index and the highest mean sensitivity rating. Alison Road had the highest diversity of species with the lowest mean sensitivity rating which suggests the quality of the water at the furthest downstream point is slightly degraded and of less quality then the upstream sites. When compared to the SIGNAL2.iv Users Guide table 2Other rivers and creeks, all sites fell within the high SPI and high taxa richness (Table 1). Table 1: Summary of SPI, SCI and # of taxa of sample sites along the Williams River, NSW.

Tillegra Bridge 6.61 5.09 46

SPI SCI # of Taxa

Bandon Grove 5.82 5.56 44

Alison Rd 6.02 5.2 58

For each site the # of taxa has been plotted against the % relative abundance to give an indication of species diversity and abundance. The # of taxa encountered at Tillegra Bridge totalled 48. The % relative abundance was dominated the order Ephemeroptera, making up over 50% of taxa at Tillegra. Decapoda, Atyidae, Paratua australiensis was the second most represented taxa ( position 6 in plot)with 41 identified and a % relative abundance of 3.89 (Fig 7). 35 30

% Relative Abundance

25 20 15 10 5 0 1

3

5

7

9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47

# of Taxa Figure 7: Relative abundance of Macroinvertebrates at Tillegra Bridge, Williams River, NSW.

The total #of taxa encountered at Bandon Grove was 46. Ephemeroptera showed the highest %

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Kirstin Miller 3151044 relative abundance and represented the top 5 taxa 7 families and 4 genus (Fig 8).

40 35

% Relative Abundance

30 25 20 15 10 5

43 45

39 41

35 37

31 33

27 29

23 25

19 21

15 17

9 11 13

7

5

3

1

0

# of Taxa FIgure 8:Relative abundance of Macroinvertebrates at Bandon Grove, Williams River, NSW.

Decapoda, Atyidae, Paratua australiensis was the second most represented taxa with 19 representatives and a sensitivity rating of 3.Diversity was greatest at Alison Rd with 57 taxa identified. Ephemeroptera had the highest relative abundance and hold the first two positions on the plot. Trichoptera Hydropsychidea was the third most abundant with 91 individuals counted. At Alison Rd Ephemeroptera Siphlonuridae were identified 40, the highest number of individuals recorded with a sensitivity rating of 10 at any of the sites closely followed by Plecoptera with a count of 35 (Fig 9). 30

% Relative Abundance

25 20 15 10 5 0 1 3

5

7

9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57

# of taxa Figure 9: Relative abundance of Macroinvertebrates at Alison Rd, Williams River, NSW.

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Kirstin Miller 3151044 The most abundant macro invertebrate species across sites was identified to family Ephemeroptera Baetidae (705 individuals) with a sensitivity rating of 5. Tillegra Bridge had the highest diversity of organisms with a level 10 sensitivity rating with 6 taxa however none exceeding 10 individuals. Thirteen (13) taxa with a sensitivity rating 3 and under were present at Tillegra. Three (3) level 10 taxa was identified at Bandon Grove with no more than 8 individuals recorded for any taxa. Twelve (12) taxa with a sensitivity rating of 3 and under were present at Bandon Grove. Taxa with a level 10 sensitivity rating at Alison Rd totalled 3 with two of the taxa being the most representative of level 10 sensitivity of all sites. Nineteen (19) of the 57 taxa identified at Alison Rd had a rating of level 3 and under (Appendix b). Discussion This study has aimed to assess the variation in water quality and macro invertebrate assemblages at three different sites along the Williams River. The results however are not indicative of true values due to variations in data and the misidentification of macro invertebrates. The nutrients levels of the sample sites were consistent between sites which suggests although stock access and high erosion was evident at Tillegra Bridge this did not alter the nutrient levels enough to influence levels on a spatial scale. This may have been due to the location of sites. Tillegra had stock access which has direct input of effluent into the river. Bandon Grove had the influence of two rivers, one with continuous riparian zone and the other with high erosion upstream. Alison Rd was influenced by townships and increase agricultural lands. Differences in Nutrient levels between sites may have been apparent if the Williams River was sampled further upstream from Tillegra at a site with no stock access, no erosion and no pastoral land. The difference in Orthophosphate levels between days at Tllegra may be attributed to a high stock activity at the site between sample days. The turbidity between sites showed spatial and temporal variation. Although erosion was evident, there was no temporal difference in the turbidity at Tillegra, as this site was the least influenced by surrounding human and agricultural input to the river. The lowest turbidity between sites was at Bandon Grove this could be due to the point of sample being on the downstream side of the fishway which acts as a filter trapping sediment and debris. The highest NTU reading between sites was at Alison Rd as it is the furthest downstream and is influenced by the erosion and increase human activity upstream. Dissolved oxygen concentrations showed a decrease in the sample sites travelling downstream which follows the general trend of an unpolluted river at altitude with lower temperatures to a river influenced by biological activity, increased turbidity and inorganic and organic compounds. Increases in turbidity and decreases in DO can cause major changes in the diversity of macro invertebrates found in rivers. If turbidity becomes too high it affect the ability of

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Kirstin Miller 3151044 algae to photosynthesize thus affecting DO. If DO concentrations become too low sensitive species such as mayflies, stoneflies and caddisflies are replaced by a few kinds of pollution-tolerant species such as flies, shrimps and worm. This study has shown this difference in macro invertebrate assemblages between the furthest upstream site and the furthest downstream site which correlates with the differences in NTU and DO. Tillegra had the highest DO concentrations and the highest diversity of sensitive species whereas Alison Rd showed the lowest DO, highest turbidity, lowest diversity of sensitive species and the highest diversity of pollutant tolerant species. Despite giving the indication of being the most impacted, the site has been assessed as having a high SPI and high taxa richness. Tillegra Bridge and Bandon Grove were also assessed as having a high SPI and high taxa richness. Using the SIGNAL2 site scoring table all sites were regarded as ‘Good water quality and a diversity of habitats. It may be a well-managed site, natural bushland, or a national park’. However this is only a general indication of site conditions and should not be used to indicate the overall health of the sites. This study has shown that i) Nitrate and Orthophosphate levels did not increase further downstream due to influencing factors such as cattle access to the river and human activities as there was no significant difference in concentration between sites ii)Dissolved Oxygen does decreases the further downstream and combined with turbidity does have had an influence on macro invertebrate assemblages at Alison Rd. iii)Turbidity is higher downstream due to influence of suspended and dissolved particulate matter and the increase in input to the river from various sources along its path such as erosion.

This report is solely a rough indication of the condition of Tillegra Bridge, Bandon Grove and Alison Rd sites of the William River and may be influenced by; small replication size at sample sites, sampling methods, handling and user errors of equipment and misidentification. This study may have yielded alternative results if these errors were minimised.

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Kirstin Miller 3151044

REFERENCES Chessman, B. (2003). SIGNAL 2 – A Scoring System for Macro-invertebrate (‘Water Bugs’) in Australian Rivers, Monitoring River Heath Initiative Technical Report no 31, Commonwealth of Australia, Canberra. Hunter Water Corporation (2011a). Catchment Management Plan: Hunter Water’s eight element plan for our catchments. Retrieved from http://www.hunterwater.com.au/Resources/Documents/Plans-Strategies/CatchmentMangementPlan_FINAL_Mar2011_lowres.pdf on 16/10/2013. Hunter Water Corporation (2011c). Grahamstown Dam. Retrieved from http://www.hunterwater.com.au/Water-and-Sewer/Water-Supply/Dams-andCatchments/Grahamstown-Dam.aspx on 16/10/2013. Hunter Water Corporation (2011b). Chichester Dam. Retrieved from http://www.hunterwater.com.au/Water-and-Sewer/Water-Su...