Victorian Water Quality Monitoring Network Trend Analysis

Victorian Statewide Summary

Produced for the Department of Natural Resources and Environment by Sinclair Knight Merz Victorian Water Quality Monitoring Network Trend Analysis

Victorian Statewide Summary

Other reports in this series:

Corangamite Catchment Management Authority Area East Gippsland Catchment Management Authority Area Glenelg Catchment Management Authority Area Goulburn Catchment Management Authority Area Mallee Catchment Management Authority Area North Central Catchment Management Authority Area North East Catchment Management Authority Area Port Phillip Catchment Management Authority Area West Gippsland Catchment Management Authority Area Wimmera Catchment Management Authority Area

Prepared by W.E. Smith and R.J. Nathan Sinclair Knight Merz Executive Summary

The Victorian Water Quality Monitoring Network (VWQMN) consists of around 280 stations located throughout Victoria. A range of water quality indicators are measured at these sites, and data has been measured for up to 25 years at approximately monthly intervals. While this data set represents a substantial body of information, to date there has been no systematic and consistent analysis of the data that provides an assessment of the temporal and spatial variation of the indicators. Such analysis can provide valuable information regarding the impacts of past management practices on catchment processes, the impact of land management practices and interventions, and the likely direction of future water quality changes.

The scope of this report is to present a summary of the nature and significance of time trends in water quality data recorded at VWQMN sites across the whole of Victoria. Only stations with records greater than ten years were used, and the indicators considered were pH, turbidity, electrical conductivity (EC), total phosphorus and total nitrogen.

The information presented here summarises the results obtained from a state- wide review of water quality trends, and companion reports have been prepared that present the detailed trend results for each Victorian Catchment Management Authority. This series of reports thus provides catchment managers with a valuable source document that contains information in a form that has not been previously available.

The GAM (Generalised Additive Model) approach was used to identify the magnitude and statistical significance of the time trends. The GAM approach has a number of significant advantages over traditional trend detection techniques as it easily accommodates problems associated with periods of missing data, serial correlation, seasonality, climatic influences, and non- constant variance. Overall, the GAM approach is ideally suited to the analysis of “real world” data, and its ability to satisfy the required statistical assumptions means that any inferences drawn regarding statistical significance are robust and accurate.

The preferred GAM model adopted for the study incorporates spline functions to account for the influence of both time and streamflow, and additional functions were included to remove the effects of seasonality, serial dependence, and non-normality. In some cases there was insufficient data to fit the preferred model, and thus it was necessary to use functions based on polynomial rather than spline terms.

Results indicate a very strong Statewide trend for pH, with most trends decreasing. Similarly, electrical conductivity also shows a strong Statewide trends, with regions of increasing, decreasing and zero trends. No Statewide trend was apparent for Turbidity. For the nutrients (total phosphorus and oxidised nitrogen) there was insufficient data to draw any regional inferences.

SINCLAIR KNIGHT MERZ WC00838: R01RJN_SUM.DOC i Contents

Executive Summary i Contents ii

1. Introduction 1

2. Data Availability 2 2.1 General 2 2.2 Length and Consistency of the Data Record 2 2.3 Data Below the Detection Limit 4

3. Model Selection and Application 5 3.1 Model Selection 5 3.2 Model Form and Application 5 3.3 Characterisation of Trend 6 3.3.1 Statistical Significance of Trends 7 3.3.2 Evaluation of Regional Trends 8 3.3.3 Average Trends 9

4. Results 10 4.1 General 10 4.1.1 Summary of Statewide Trends 10 4.2 Regional Trend Results 10 4.3 Average Trend Results 17

5. Conclusions 20

Appendix A - Data Availability 21

Appendix B – Average Trends: Catchment Management Area 31

Appendix C – Average Trends: Victorian Drainage Basins 37

SINCLAIR KNIGHT MERZ WC00838: R01RJN_SUM.DOC ii 1. Introduction

The Victorian Water Quality Monitoring Network (VWQMN) consists of around 280 stations throughout Victoria. A range of water quality indicators are measured at these sites, and data has been measured for up to 25 years at approximately monthly intervals. While this data set represents a substantial body of information, to date there has been no systematic and consistent analysis of the data that provides an assessment of the temporal and spatial variation of the indicators. Such analysis can provide valuable information regarding the impacts of past management practices on catchment processes, the impact of land management practices and interventions, and the likely direction of future water quality changes.

The overall aim of this study was to investigate the nature and significance of time trends in water quality data recorded at VWQMN sites throughout Victoria. The indicators considered were pH, turbidity, electrical conductivity (EC), total phosphorus and total nitrogen, and in order to ensure that the trend results were meaningful, only those stations with at least 10 years of record were included in the analysis.

Rather than provide detailed trend results for all water quality sites across Victoria in a single report, it was decided to prepare separate documents for each region controlled by the Catchment Management Authorities (CMAs). Thus, reports have been prepared for all CMA regions within Victoria, namely: ¨ Corangamite ¨ East Gippsland ¨ Glenelg ¨ Goulburn ¨ Mallee ¨ North Central ¨ North East ¨ Port Phillip ¨ West Gippsland ¨ Wimmera

This report provides a summary of the results obtained for the individual regions. It is hoped that this series of reports will provides catchment managers with a valuable source document that contains information in a form that has not been previously available.

This report presents a summary of the data availability (Section 2), the general approach used for the study (Section 3), and a description of the results obtained (Section 4).

1 2. Data Availability

2.1 General

Five pollutants were investigated for trend: pH, turbidity (Tb), electrical conductivity (EC), total phosphorus (TP) and total nitrogen (TN). Data was available at approximately 280 sites across Victoria, although not all pollutants have been sampled at every site. Significantly more data was available for pH, turbidity and electrical conductivity than for total phosphorus or total nitrogen.

Figure 1 shows the location of all monitoring sites across Victoria and the range of pollutants that are sampled at each. All sites are referenced by a Site Identification Number (SINo) that uniquely identifies the information within the VWQMN data base. Superimposed over the site locations are the Catchment Management Authority (CMA) boundaries. A summary table of data availability within each of the Catchment Management Authorities is presented in Appendix A.

2.2 Length and Consistency of the Data Record

The length of the data record varies with each site and the maximum length of available record is around 20 years. To ensure that any inferences regarding trend are robust and meaningful, a minimum record length 10 years was adopted for all analyses. The VWQMN was established around 20 years ago, and thus all results presented in this report reflect trends that have occurred over (approximately) the last 10 to 20 years.

Observations are generally available at a monthly time step. As described in Section 3.0, the method used to remove the influence of serial dependence between observations requires the adoption of a fixed time step, and therefore a regular step of one month was adopted for all analyses. The preparation of data into a regular monthly time series presented two problems as follows: ¨ Samples were not taken in some months, and these months were therefore regarded as containing missing data. It should be noted that total nitrogen and total phosphorus had substantial amounts of ‘missing’ data as the early part of each data set had generally been sampled at three monthly intervals. ¨ Some sites had been sampled more than once in a month, and thus it was necessary to aggregate the observations to represent a single value. This aggregation was achieved using a simple arithmetic mean of the values within the interval. It should be noted that there were very few intervals with more than one sample and thus the aggregation represents very little compression (or loss) of data.

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Some data was reported as being less than a certain value (ie ‘< 0.005mg/l’) indicating that the measured concentration was less than the detection limit of the measuring technique. This was particularly a problem for the nutrient indicators, ie total phosphorus and oxidised nitrogen.

There are several possible approaches to dealing with this type of data. For example, the data could be treated as missing or else set to half the magnitude of the reporting limit.

There is no generally accepted approach to dealing with data below the reporting limit. While certain non-parametric approaches to trend analysis are not affected by such observations, it is usually necessary to treat the data in some manner to ensure that systematic error is not introduced into the analyses. For this study, all data recorded as being below the detection limit were simply set equal to the detection limit. Across the whole State, data treated in this manner represented less than 2% of the total sample, and therefore the manner of treatment is not expected to influence the results.

4 3. Model Selection and Application

3.1 Model Selection

There are many techniques available for the analysis of trends in data, each of which relies on different statistical assumptions. Differentiation between the techniques is based largely on the power of each technique to correctly detect trends given the properties of the particular data set under consideration. For example, substantial periods of missing data, as are commonly found in hydrologic time series, can drastically reduce the ability of a particular technique to detect the trend.

Recently Morton (1996) demonstrated the advantages of a parametric method, the Generalised Additive Model (GAM), to estimate time trends in hydrologic time series data. Morton showed how the technique can easily be used to satisfy all required assumptions. In particular, he highlights that the GAM approach is generally more flexible, and allows non-linear time trends and exogenous influences to be easily accommodated. Morton also makes the important point that existing non-parametric techniques do not cope very well with serially correlated data, a problem that is easily rectified with the GAM approach by the inclusion of an autoregressive term. An informal description of the GAM approach, and examples that illustrate application of the technique to a range of problems commonly encountered in hydrologic trend detection, is presented by Nathan et al. (1999).

In common with many trend tests, the main assumptions that need to be satisfied with the GAM technique are that the residuals must: (i) be normally distributed, (ii) have constant variance, and (iii) be serially independent. As discussed in Section 3.0, the latter assumption can usually be satisfied by jointly fitting a time series model. Errors associated with the remaining assumptions can usually be minimised by applying appropriate transformations to the data.

3.2 Model Form and Application

A GAM model can be formulated as follows:

y = b0 + b1f(x1) + b2f(x2) + … bnf(xn) + f(e) (1)

where y is the water quality time series suspected of containing a trend, x1, x2, x3 …. xn are explanatory variables, b0 is a constant, and e is an error term. In essence, the form of the model is similar to that used in multiple regression, though in the context of water quality trend detection, the explanatory variables may represent functional relationships between y and some other hydrologic time series, or else they may represent some other time-based function altogether. Importantly, all functional relationships incorporated into the model are fitted jointly.

5 In this study, the choice of explanatory variables was made on the basis of preliminary analysis of the data sets and previous experience. Streamflow, measured at the time of sampling of the pollutant was included as the magnitude of flow has a major influence on the pollution concentration. A seasonal component was also added to account for variability in the pollutant concentrations with time of year. Lastly, a time component was included to enable the assessment of the significance of trends with time. Logarithmic transformations were used to normalise selected variables in order to help normalise the residuals.

The appropriateness of several model forms were investigated for this study and two were adopted for use. The preferred model is based on the use of spline functions to account for the influence of time and flow, and the other model is based on polynomial functions. A lag-one autoregressive model was fitted to the residuals to satisfy the assumption of serial independence; incorporation of this term thus ensures that the residuals of the current time step are not correlated with the residuals from the previous time step. Outliers were excluded using an objective criterion based on Cook’s statistic, and diagnostic plots were used to check that model assumptions were not violated.

Further details concerning the formulation and application of the GAM models may be found in the accompanying detailed reports prepared for each Catchment Management Authority.

3.3 Characterisation of Trend

The form of the adopted GAM models allow the evaluation of non-linear trends. Such models clearly illustrate the variation in trend over time, and in particular the spline form of the model allows a visual assessment of trend similar to that achieved using LOWESS plots (Cleveland, 1979). While plots of non-linear time trends allow inferences to be made regarding the nature (and hence possible causes) of trends over the historic period, they are not suited to providing a simple estimate of average annual trends.

Consider the example given in Figure 3.1 for which there is a clear, non-linear trend present in the data (as illustrated by the solid curvilinear line). The variation through time indicates a cyclic trend, in which an initial period of increasing trend is followed by decreasing values, and another subsequent period of increases. Such information, when combined with local knowledge of land-use changes or operational conditions, can provide a valuable basis on which to assess the causes of trends.

Figure 3.1 does not make it clear, however, whether there has been an overall increase or decrease in the linear component of the observed trend. In order to characterise this overall trend, a linear regression line has been fitted through the non-linear trend results, as illustrated by the broken line in Figure 3.1. This estimate of the linear component of the trend has been used to 6 represent the overall trend at each site, and is used to construct “arrow” plots that reveal the degree of uniformity in trend results throughout a region (see Section 3.3.2).

3.3.1 Statistical Significance of Trends

In addition to the magnitude of the trend, the statistical significance of the trend also needs to be estimated. The significance indicates whether the trend can be validly discerned from within the noise of the data.

Significance is determined from a t-test on the linear component of the time trend in the GAM model. A t-test is an expression of the probability that the nature of the trend has been accurately discerned from the data. The significance has therefore been reported at the 5% level (indicating a high probability of significance), 10% level (indicating a medium level of significance) and Nil (indicating that the trend is not significant).

Figure 3.1: Illustration of the non-linear and linear components of trend (for electrical conductivity for station 229214 in the Port Phillip CMA).

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7 3.3.2 Evaluation of Regional Trends

In addition to the reporting of trends at each site, maps indicating regional trends have also been produced. The maps use arrows to indicate the nature of the trend with the magnitude, direction and significance of the trend being illustrated by the direction, size, and shading of the arrows. The consistency of any regional trends are reflected in the consistency of the size and direction of the arrows.

An illustration of the symbols used is provided in Figure 3.2. A red arrow pointing vertically upwards indicates an upwards trend and a blue arrow pointing vertically downwards indicates a downwards trend. The size of the arrows indicates the relative magnitude of the overall linear trend, and a green circle indicates that the magnitude of the trend is approximately zero. Note that ‘zero’ has been set differently for each pollutant based on reasonable detection limits for that pollutant and are listed as follows: ¨ pH : -0.025< ’zero’ <0.025 (/yr) ¨ turbidity : -0.25< ’zero’ <0.025 (NTU/yr) ¨ electrical conductivity: -5.0< ’zero’ <5.0 (µs/cm/yr) ¨ total phosphorus: -0.5< ’zero’ <0.5 (µg/L/yr) ¨ total nitrogen: -0.003< ’zero’ <0.003 (mg/L/yr)

In addition to lower limits, upper limits have also been set to prevent one large trend dominating the size of arrows across the whole map. The following upper limits have been adopted: ¨ pH: 0.1 (/yr) ¨ turbidity: 1 (NTU/yr) ¨ electrical conductivity: 25 (µs/cm/yr) ¨ total phosphorus: 10.0 (µg/l/yr) ¨ total nitrogen: 0.05 (mg/l/yr)

Note that the magnitude of trends that exceed the above limits are marked in colour near the station number on the arrow map.

If an arrow or circle is infilled with solid colour then the trend is significant at the 5% level; if infilled with a shaded colour then the trend is significant at the 10% level, and if there is no infilling then the trend is not significant.

It should be noted that stations for which the estimated trend was not reliable do not have an arrow on the map, they simply have the station number. Station numbers have also been marked for total phosphorus and total nitrogen where there was insufficient data for analysis.

8 Figure 3.1: Key for arrow plots KEY Direction and Significance of change Magnitude of change ( m s/cm/yr) NIL 10% 5% Positive 5

15 +/- 5 25 Negative NIL 10% 5%

3.3.3 Average Trends

A summary of the information contained in the regional arrow maps has been produced in the form of an average catchment trend. The average has been computed by areally weighting the statistically significant trends as shown in Equation 2.

Ta= (T1A1+T2A2+……TnAn)/SA (2)

Where: Ta = areally weighted average trend

T1..n = statistically significant trend for stations 1 to n 2 A1 ..n = catchment area corresponding to the trend (km )

Areally weighted average trends have been produced for each of the ten CMA regions (for each of the five pollutants) and each of the Victorian River Drainage Basins. It should be noted that the monitoring stations sited on the Murray River have not been included in the estimation.

9 4. Results

4.1 General

This section presents a summary of the trend results obtained for all stations across the State. Detailed results for each Catchment Management Authority may be found in the relevant companion reports. Results are summarised here in three ways: (i) the frequency of occurrence of a range of statistically significant trends, (ii) statewide arrow plots and (iii) average trend results.

4.1.1 Summary of Statewide Trends

Frequency distributions of a range of statistically significant trends are illustrated in Figure 4.1. Frequencies are generally provided for uniform intervals, though it should be noted that the middle interval corresponds to the limits used to characterise “zero” trends, as discussed in Section 3.3.2.

It is expected that the results summarised in Figure 4.1 can be used to help place in context the trends obtained for a specific site. For example, it is seen that the majority of statistically significant trends in electrical conductivity are approximately zero (ie within the range ± 5 ms/cm/yr, and that statewide nearly all statistically significant trends lie between an average annual trend of -80 mS/cm and 5 mS/cm. Thus, if a positive trend of greater than 5 mS/cm was obtained for a particular site, then it is seen that such a result should be considered unusual.

The results presented in Figure 4.1 indicate that: ¨ electrical conductivity trends are generally negative, between +5 and -80ms/m/yr; ¨ total nitrogen trends are generally between -0.04 and 0.04 mg/l/yr; ¨ total phosphorous trends are generally zero (ie between -0.5 and 0.5mg/l/yr); ¨ turbidity trends are generally between -1.0 and 2.0 NTU/yr; ¨ pH trends are generally negative, between -0.1 and 0.025 /yr

4.2 Regional Trend Results

A statewide arrow map has been produced for each water quality indicator (see Figures 4.2 to 4.6). The strongest regional trend is shown for pH, for which the majority of non-zero trends are decreasing. The magnitude of most trends in the Gippsland region are small compared to the rest of the State.

For electrical conductivity (Figure 4.3), decreasing trends are common in the Southern Central region of the State. Conversely, in the Western and North Western regions, the trends are predominantly increasing and in the Eastern region (Gippsland), the trends are predominantly zero.

10 Figure 4.1 Frequency of significant trends in water quality indicators for all sites in Victoria

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ƒ IH H IH PH QH uilometers ƒ„e„i‡shi2„‚ixh2exev‰ƒsƒƒ„e„i‡shi2„‚ixh2exev‰ƒsƒ w—gnitude2—nd2signifi™—n™e2of2trend2inw—gnitude2—nd2signifi™—n™e2of2trend2in „ot—l2€hosphorus2@22gGvGyrA„ot—l2€hosphorus2@22gGvGyrAm pigure2RFT iX’w™ms’w™HHVQV’™—d’—r™view’†sgE„€Y2†sgE„€ Regional patterns are not readily evident for turbidity (Figure 4.2) with approximately equal number of increasing and decreasing trends. The strongest indication of regional trend comes from the North Eastern regions of Gippsland where the large majority of trends are of zero magnitude.

For total phosphorus and total nitrogen (Figures 4.5 and 4.6) there are too few data sets from which to draw substantial conclusions about region. Port Phillip, East Gippsland and North East regions have the most number of non- zero trends - all of which are decreasing in the East Gippsland and North East regions. For total phosphorus, the majority of trends have zero magnitude with only a minor scattering of non-zero trends. It should noted however that some of the non-zero trends are quite substantial (eg a negative trend of 109µg/l/yr in the Port Phillip region).

4.3 Average Trend Results

Areally weighted average trends have been determined for each CMA and each Victorian Drainage Basin using Equation 2. It should be noted that only statistically significant trends have been included in the determination of average trend; for some regions and some pollutants this has resulted in there being no data available for determination of the average trend.

Table 4.1 and Table 4.2 show the areally weighted trends and the corresponding catchment areas for the CMA basins and the Victorian Drainage Basins respectively. These tables also indicate the percentage of the catchment area on which the trend estimates have been based.

Table 4.1 : Areally weighted trends for each CMA

CMA CMA Area Proportion of Areally Weighted Trends (km2) Area Upstream pH Turbidity Electrical Total Nitrogen Total of Gauging (NTU/Yr) Conductivity (mg/l/Yr) Phosphorus Station (%) (ms/cm/Yr) (mg/l/yr) Corangamite 13353 79 0.000 0.00 -21.7 0.042 -4.3 East Gippsland 22042 69 0.000 0.00 0.0 -0.01 0.0 Glenelg 26778 86 0.000 0.00 20.7 0.005 0.0 Goulburn 24064 85 -0.036 0.38 0.0 -0.013 6.2 Mallee 39310 N/A N/A N/A N/A N/A N/A North Central 29630 72 0.000 0.00 27.1 0.000 2.9 North East 18825 68 -0.046 0.00 0.0 -0.009 0.7 Port Phillip 12793 60 0.000 0.00 -9.3 -0.032 -9.9 West Gippsland 17293 58 0.000 -0.38 0.0 0.000 0.0 Wimmera 23494 26 0.000 -2.08 22.3 N/A N/A Note: N/A indicates results are not available

17 Table 4.2: Areally weighted trends for each Victorian Drainage Basin

Basin Name Basin Catchment Area Proportion of Areally Weighted Trends No. Area Upstream pH Turbidity Electrical Total Nitrogen Total of Gauging (NTU/Yr) Conductivity (mg/l/Yr) Phosphorus Station (%) (ms/cm/Yr) (mg/l/yr) Upper Murray 1 10150 58 -0.037 0.00 0.0 -0.009 -1.0 Kiewa 2 1913 89 -0.048 0.00 0.0 -0.007 0.0 Ovens 3 7984 80 -0.046 0.00 0.0 -0.008 3.1 Broken 4 7099 83 0.000 1.13 0.0 N/A 7.0 Goulburn 5 16858 85 -0.037 0.00 0.0 -0.013 2.0 Campaspe 6 4048 86 -0.044 0.31 -6.8 N/A 0.5 Loddon 7 15657 88 0.000 0.00 10.0 0.000 3.9 Avoca 8 14210 24 0.029 0.00 160.3 N/A N/A Mallee 14 21594 0 N/A N/A N/A N/A N/A Wimmera 15 30409 22 0.000 -2.22 20.8 N/A N/A East Gippsland 21 4518 43 0.000 0.00 0.0 -0.008 -0.8 Snowy 22 6824 77 -0.030 0.00 0.0 -0.008 0.0 Tambo 23 4213 72 0.000 0.00 0.0 -0.019 N/A Mitchell 24 4873 80 0.000 0.00 0.0 -0.013 1.0 Thomson 25 6426 69 0.000 0.00 0.0 N/A N/A La Trobe 26 4677 86 0.000 -0.7 0.0 -0.004 0.0 South Gippsland 27 6877 26 0.000 0.31 0.0 0.011 2.0 Bunyip 28 4078 36 -0.032 0.00 -6.2 -0.108 -109.0 Yarra 29 4110 71 0.000 0.00 0.0 N/A -3.0 Maribyrnong 30 1453 90 0.000 0.00 -11.5 -0.011 -1.0 Werribee 31 1979 71 -0.033 -0.28 -12.3 -0.050 -1.0 Moorabool 32 2224 69 -0.032 0.00 12.5 N/A N/A Barwon 33 3806 82 0.000 0.00 -35.3 0.048 -18.0 Corangamite 34 4081 35 0.000 0.00 -40.1 -0.030 1.0 Otway 35 3876 51 0.000 0.00 0.0 N/A 1.0 Hopkins 36 10096 94 0.000 0.00 27.9 0.000 0.9 Portland 37 3963 59 0.000 0.00 10.2 -0.006 0.0 Glenelg 38 11988 93 0.000 0.00 -9.8 0.008 0.0 Millicent Coast 39 7426 1 N/A N/A N/A N/A N/A Note: N/A indicates results are not available

The arrow maps are shown in Appendix B for the CMA regions and Appendix C for each Victorian Drainage Basin. Consider the CMA regions first. A high proportion of zero magnitude trends is evident for pH with only two negative trends in the Goulburn and North East CMA regions. For electrical conductivity (EC), regional patterns in the nature of trends are apparent with decreasing trends in the southern central region, increasing trends in the western region and trends of zero magnitude in the eastern. No regional patterns are evident for turbidity although there is a predominance of zero

18 magnitude trends. Total nitrogen exhibits a minor regional pattern with decreasing trends in the north east of the state and decreasing trends in the south west of the State. The only evident regional pattern in trends for Total phosphorus is in the north of the State where the trends are increasing.

Consider the arrow maps for the Victorian Drainage Basins, shown in Appendix C. On a regional scale, these maps show trend patterns similar to the CMA maps with some minor variations dependent upon the local trend and representative catchment area.

19 5. Conclusions

Water quality data from the VWQMN (Victorian Water Resources Monitoring Network) have been analysed to determine trends. Approximately 280 stations were investigated for trends in pH, turbidity and electrical conductivity. Substantially less nutrient data (total phosphorus and total nitrogen) was available, with approximately 94 stations analysed for trend.

The GAM (Generalised Additive Models) method was used to determine the trends. GAM is particularly suited to investigating trends in water quality data as it accounts for the effects of exogenous influences (such as streamflow) and it easily deals with the common problems of missing data and serial correlation.

Strong regional trends are apparent for pH and electrical conductivity. Electrical conductivity shows regions of increasing, decreasing and zero trend whilst pH shows predominantly decreasing trends. Turbidity shows very little regional trend patterns, with increasing, decreasing and zero trends appearing equally. Regional patterns were more difficult to discern due to the substantially less data available.

The information presented here summarises the results obtained from a state- wide review of water quality trends, and companion reports have been prepared that present the detailed trend results for each Victorian Catchment Management Authority. This series of reports thus provides catchment managers with a valuable source document that contains information in a form that has not been previously available.

20 Appendix A - Data Availability

The data analysed for each Catchment Management Authority is shown in Tables A1 to A10.

Table A1: Corangamite Catchment Management Authority Station Station Name pH Tb EC TN Tp Number 232202 Moorabool River @ Batesford ü ü ü ü ü 232204 Moorabool River @ Morrisons ü ü ü 232210 Moorabool River West Branch @ Lal Lal ü ü ü ü ü 232211 Moorabool River West Branch @ Mount Doran ü ü ü 233200 Barwon River @ Pollocksford ü ü ü ü ü 233211 Birregurra Creek @ Ricketts Marsh ü ü ü 233214 Barwon River East Branch @ Forrest (Above Tunnel) ü ü ü 233215 Leigh River @ Mount Mercer ü ü ü ü ü 233218 Barwon River @ Inverleigh ü ü ü 233223 Warrambine Creek @ Warrambine ü ü ü ü ü 233224 Barwon River @ Ricketts Marsh ü ü ü 233228 Boundary Creek @ Yeodene ü ü ü 234200 Woady Yaloak River @ Pitfield ü ü ü ü ü 234201 Woady Yaloak River @ Cressy (Yarima) ü ü ü 234203 Pirron Yallock Creek @ Pirron Yallock (Above H'Wy Br.) ü ü ü ü ü 235202 Gelibrand River @ Upper Gelibrand ü ü ü 235203 Curdies River @ Curdie ü ü ü 235204 Little Aire Creek @ Beech Forest ü ü ü 235205 Arkins Creek West Branch @ Wyelangta ü ü ü 235208 Gellibrand River @ Carlisle ü ü ü 235209 Aire River @ Beech Forest ü ü ü 235210 Lardner Creek @ Gellibrand ü ü ü 235211 Kennedys Creek @ Kennedys Creek ü ü ü 235212 Chapple Creek @ Chapple Vale ü ü ü 235216 Cumberland River @ Lorne ü ü ü 235219 Aire River @ Wyelangta ü ü ü 235223 Scotts Creek @ Scotts Creek ü ü ü 235224 Gellibrand River @ Burrupa ü ü ü ü ü 235226 St. George River @ Allenvale ü ü ü 235227 Gellibrand River @ Bunkers Hill ü ü ü ü ü 235229 Ford River @ Glenaire ü ü ü 235232 Painkalac Creek @ Painkalac Creek Dam ü ü ü 235233 Barham River East Branch @ Apollo Bay, Paradise ü ü ü

21 Table A2: East Gippsland Catchment Management Authority Station Station Name pH Tb EC TN Tp Number 221201 Cann River (West Branch) @ Weeragua ü ü ü ü ü 221207 Errinundra River @ Errinundra ü ü ü 221208 Wingan River @ Wingan Inlet National Park Basin 21 E.G. ü ü ü 221209 Cann River (East Branch) @ Weeragua ü ü ü 221210 Genoa River @ The Gorge ü ü ü ü ü 221211 Combienbar River @ Combienbar Basin 21 East Gippsland ü ü ü 221212 Bemm River @ Princes Highway ü ü ü ü ü 222200 Snowy River @ Jarrahmond ü ü ü ü ü 222202 Brodribb River @ Sardine Creek Basin 22 Snowy ü ü ü ü ü 222206 Buchan River @ Buchan ü ü ü ü ü 222209 Snowy River @ Mckillop Bridge ü ü ü 222210 Deddick River @ Deddick (Caseys) ü ü ü 222213 Suggan Buggan River @ Suggan Buggan ü ü ü 222217 Rodger River @ Jacksons Crossing ü ü ü 222219 Snowy River @ Downstream Of Basin Creek ü ü ü 223202 Tambo River @ Swifts Creek ü ü ü ü ü 223204 Nicholson River @ Deptford ü ü ü 223205 Tambo River @ Downstream Of Ramrod Creek ü ü ü ü ü 223208 Tambo River @ Bindi (Near Junction Creek) ü ü ü ü ü 223212 Timbarra River @ Downstream Of Wilkinson Creek ü ü ü 223213 Tambo River @ Downstream Of Duggan Creek ü ü ü 223214 Tambo River @ Upstream Of Smith Creek ü ü ü 224201 Wonnangatta River @ Waterford ü ü ü ü ü 224203 Mitchell River @ Glenaladale ü ü ü ü ü 224206 Wonnangatta River @ Crooked River ü ü ü ü ü 224207 Wongungarra River @ Guys ü ü ü 224209 Cobbannah Creek @ Near Bairnsdale ü ü ü 224213 Dargo River @ Lower Dargo Road ü ü ü 224214 Wentworth River @ Tabberabbera ü ü ü 224215 Mitchell River @ Angusvale (Tabberabbera) ü ü ü

22 Table A3 : Glenelg Catchment Management Authority Station Station Name pH Tb EC TN Tp Number 236202 Hopkins River @ Wickliffe ü ü ü 236203 Mount Emu Creek @ Skipton ü ü ü 236204 Fiery Creek @ Streatham ü ü ü 236205 Merri River @ Woodford ü ü ü ü ü 236209 Hopkins River @ Hopkins Falls ü ü ü ü ü 236210 Hopkins River @ Framlingham ü ü ü 236212 Brucknell Creek @ Cudgee ü ü ü ü ü 236213 Mount Emu Creek @ Mena Park ü ü ü 236216 Mount Emu Creek @ Taroon (Ayrford Road Bridge) ü ü ü 237200 Moyne River @ Toolong ü ü ü ü ü 237202 Fitzroy River @ Heywood ü ü ü 237205 Darlot Creek @ Homerton Bridge ü ü ü 237206 Eumeralla River @ Codrington ü ü ü ü ü 237207 Surry River @ Heathmere ü ü ü 238202 Glenelg River @ Sandford ü ü ü ü ü 238204 Wannon River @ Dunkeld ü ü ü ü ü 238206 Glenelg River @ Dartmoor ü ü ü ü ü 238207 Wannon River @ Jimmy Creek ü ü ü 238208 Jimmy Creek @ Jimmy Creek ü ü ü 238212 Glenelg River @ Casterton ü ü ü 238218 Wannon River @ Wannon Falls ü ü ü 238219 Grange Burn @ Morgiana ü ü ü 238221 Dwyer Creek @ Mirrantawa ü ü ü 238223 Wando River @ Wando Vale ü ü ü 238224 Glenelg River @ Fulham Bridge ü ü ü 238225 Wannon River @ Burrah ü ü ü 238228 Wannon River @ Henty ü ü ü 238229 Chetwynd River @ Chetwynd ü ü ü 238230 Stokes River @ Teakettle ü ü ü 238231 Glenelg River @ Big Cord ü ü ü ü ü 238234 Pigeon Ponds Creek @ Koolomert ü ü ü 238235 Crawford River @ Lower Crawford ü ü ü 238238 Henty Creek @ Henty ü ü ü

23 Table A4 : Goulburn Catchment Management Authority Station Station Name pH Tb EC TN Tp Number 404206 Broken River @ Moorngag ü ü ü 404207 Holland Creek @ Keelera ü ü ü ü ü 404208 Moone Creek @ Lima ü ü ü 404210 Broken Creek @ Rices Weir ü ü ü ü ü 404214 Broken Creek @ Katmatite ü ü ü 404216 Broken River @ Goorambat ü ü ü ü ü 405200 Goulburn River @ Murchison ü ü ü ü ü 405202 Goulburn River @ Seymour ü ü ü ü ü 405203 Goulburn River @ Eildon ü ü ü 405204 Goulburn River @ Shepparton ü ü ü ü ü 405205 Murrindindi River @ Murrindindi Above " Colwells" ü ü ü 405209 Acheron River @ Taggerty ü ü ü 405212 Sunday Creek @ Tallarook ü ü ü 405214 Delatite River @ Tonga Bridge ü ü ü 405215 Howqua River @ Glen Esk ü ü ü 405217 Yea River @ Devlins Bridge ü ü ü 405218 Jamieson River @ Gerrans Bridge ü ü ü 405219 Goulburn River @ Dohertys ü ü ü 405227 Big River @ Jamieson ü ü ü ü ü 405228 Huges Creek @ Tarcombe Road ü ü ü 405229 Wanalta Creek @ Wanalta ü ü ü 405230 Cornella Creek @ Colbinabbin ü ü ü 405231 King Parrot Creek @ Flowerdale ü ü ü 405232 Goulburn River @ Mccoy Bridge ü ü ü ü ü 405234 Seven Creek Downstream Of Polly Mcquinn Weir ü ü ü 405240 Sugarloaf Creek @ Ash Bridge ü ü ü 405241 Rubicon River @ Rubicon ü ü ü 405245 Fords Creek @ Mansfield ü ü ü 405246 Castle Creek @ Arcadia ü ü ü 405247 Stony Creek @ Tamleugh ü ü ü 405248 Major Creek @ Graytown ü ü ü 405251 Brankeet Creek @ Ancona ü ü ü 405257 Snobs Creek @ Snobs Creek Hatchery ü ü ü 405261 Spring Creek (Colonial Creek ) @ Fawcett ü ü ü 405263 Goulburn River Upstream Of Snake Creek Junction ü ü ü 405264 Big River Downstream Of Frenchman Creek Junction ü ü ü 409202 Murray River @ Tocumal ü ü ü ü ü 409215 Murray River @ Barmah ü ü ü

24 Table A5 : Mallee Catchment Management Authority Station Station Name pH Tb EC TN Tp Number 414201 Murray River @ Boundary Bend ü ü ü 414204 Murray River @ Red Cliffs ü ü ü 414207 Murray River @ Colignan ü ü ü 409213 Murray River @ Piangil ü ü ü

25 Table A6: North Central Catchment Management Authority Station Station Name pH Tb EC TN Tp Number 406202 Campaspe River @ Rochester ü ü ü ü ü 406207 Campaspe River @ Eppalock ü ü ü ü ü 406213 Campaspe River @ Redesdale ü ü ü ü ü 406214 Axe Creek @ Longlea ü ü ü 406215 Coliban River @ Lyal ü ü ü 406224 Mount Pleasant Creek @ Runnymede ü ü ü 406235 Wild Duck Creek @ Upstream Of Heathcote-Mia Mia Road ü ü ü 407202 Loddon River @ Kerang ü ü ü ü ü 407203 Loddon River @ Laanecoorie ü ü ü ü ü 407205 Loddon River @ Appin South ü ü ü 407209 Gunbower Creek @ Koondrook ü ü ü ü ü 407213 Mccallums Creek @ Carisbrook ü ü ü 407214 Creswick Creek @ Clunes ü ü ü ü ü 407215 Loddon River @ Newstead ü ü ü ü ü 407217 Loddon River @ Vaughan, Downstream Fryers Creek ü ü ü 407220 Bet Bet Creek @ Norwood ü ü ü 407221 Jim Crow Creek @ Yandoit ü ü ü 407222 Tullaroop Creek @ Clunes ü ü ü 407227 Birch Creek @ Smeaton ü ü ü 407230 Joyces Creek @ Strathlea ü ü ü 407236 Mount Hope Creek @ Mitiamo ü ü ü 407252 Barr Creek @ Capels Flume ü ü ü ü ü 407253 Piccaninny Creek @ Minto ü ü ü 408200 Avoca River @ Coonooer ü ü ü ü ü 408202 Avoca River @ Amphitheatre ü ü ü 408203 Avoca River @ Quambatook ü ü ü 408204 Glenlogie Creek @ Amphitheatre ü ü ü 409005 Murray River @ Barham ü ü ü ü ü 409204 Murray River @ Swan Hill ü ü ü ü ü 409207 Murray River @ Torrumbarry ü ü ü 415220 Avon River @ Wimmera Highway ü ü ü 415224 Avon River @ Beazley'S Bridge ü ü ü 415226 Richardson River @ Carrs Plains ü ü ü

26 Table A7: North East Catchment Management Authority Station Station Name pH Tb EC TN Tp Number 401201 Murray River @ Jingellic ü ü ü ü ü 401203 Mitta Mitta River @ Hinnomunjie ü ü ü ü ü 401204 Mita Mita @ Tallandoon ü ü ü ü ü 401208 Cudgewa Creek @ Berringama ü ü ü 401210 Snowy Creek @ Below Granite Flat ü ü ü 401211 Mitta Mitta River @ Colemans ü ü ü ü ü 401212 Narriel Creek @ Upper Nariel ü ü ü 401215 Morrass Creek @ Uplands ü ü ü 401216 Big River @ Jokers Creek ü ü ü 401217 Gibbo River @ Gibbo Park ü ü ü 401220 Tallangatta Creek @ Mccallums ü ü ü 401226 Victoria River @ Victoria Falls ü ü ü 402203 Kiewa River @ Mongans Bridge ü ü ü ü ü 402204 Yackandandah Creek @ Osbornes Flat ü ü ü ü ü 402205 Kiewa River @ Bandiana ü ü ü 402206 Running Creek @ Running Creek ü ü ü 402222 Kiewa River @ Kiewa (Main Stream) ü ü ü ü ü 403200 Ovens River @ Wangaratta (Epa Site) ü ü ü ü ü 403205 Ovens River @ Bright (Epa Site) ü ü ü ü ü 403209 Reedy Creek @ Wangaratta North ü ü ü ü ü 403210 Ovens River @ Myrtleford ü ü ü 403213 Fifteen Mile Creek @ Greta South ü ü ü 403214 Happy Valley Creek @ Rosewhite ü ü ü 403217 Rose River @ Matong North ü ü ü 403218 Dandongadale River @ Matong North ü ü ü 403220 Buffalo River @ Lake Buffalo ü ü ü 403222 Buffalo River @ Abbeyard ü ü ü 403224 Hurdle Creek @ Bobinawarrah ü ü ü 403226 Boggy Creek @ Angleside ü ü ü 403227 King River @ Cheshunt ü ü ü 403230 Ovens River @ Rocky Point ü ü ü ü ü 403232 Morses Creek @ Wandiligong ü ü ü 403233 Buckland River @ Harris Lane ü ü ü 403241 Ovens River @ Peechelba East ü ü ü ü ü 403244 Ovens River @ Harrietville ü ü ü

27 Table A8 : Port Phillip Management Authority Station Station Name pH Tb EC TN Tp Number 228201 Tarago River @ Drouin West ü ü ü 228204 Dandenong Creek @ Dandenong ü ü ü ü ü 228206 Tarago River @ Neerim ü ü ü 228207 Bunyip River @ The Headworks ü ü ü 228209 Lang Lang River @ Hamiltons Bridge ü ü ü ü ü 228212 Bunyip River @ Tonimbuk ü ü ü 228213 Bunyip River @ Iona ü ü ü ü ü 228214 Diamond Creek @ Bunyip North ü ü ü 228217 Toomuc Creek @ Pakenham ü ü ü 228219 Tarago River @ Neerim South ü ü ü 228226 Stony Creek @ Shoreham ü ü ü 228228 Cardinia Creek @ Cardinia ü ü ü 229200 Yarra River @ Warrandyte ü ü ü ü ü 229212 Yarra River @ Millgrove ü ü ü 229214 Little Yarra River @ Yarra Junction ü ü ü ü ü 229215 Woori Yallock Creek @ Woori Yallock ü ü ü 229216 Plenty River @ Mernda ü ü ü 229218 Watsons Creek @ Watsons Creek ü ü ü 229220 Don River @ Launching Place ü ü ü 229223 Diamond Creek @ Diamond Ck ü ü ü 230200 Maribyrnong River @ Keilor ü ü ü ü ü 230202 Jackson Creek @ Sunbury ü ü ü 230204 Riddells Creek @ Riddells Ck ü ü ü ü ü 230205 Deep Creek @ Bulla (Downstream Of Emu Creek Junction) ü ü ü 230206 Jackson Creek @ Gisborne ü ü ü ü ü 230208 Maribyrnong River @ Darraweit Guim ü ü ü 230209 Barringo Creek @ Barringo (Upstream Of Diversion) ü ü ü 230210 Saltwater Creek @ Bullengarook ü ü ü ü ü 230211 Emu Creek @ Clarkefield ü ü ü ü ü 230213 Turritable Creek @ Mt Macedon ü ü ü 230214 Willimigongon Creek @ Mt Macedon ü ü ü 231201 Lerderderg River @ Darley ü ü ü 231203 Pykes Creek @ Pykes Creek Reservoir ü ü ü ü ü 231204 Werribee River @ Werribee (Diversion Weir) ü ü ü ü ü 231205 Werribee River @ Melton Reservoir ü ü ü 231213 Lerderberg River @ Sardine Creek (O'Briens Crossing) ü ü ü ü ü 231225 Werribee River @ Ballan (Upstream Old Western Hwy ü ü ü ü ü Bridge) 231231 Toolern Creek @ Melton South ü ü ü 232200 Little River @ Little River ü ü ü

28 Table A9 : West Gippsland Catchment Management Authority Station Station Name pH Tb EC TN Tp 227231 Bass River @ Glen Forbes South ü ü ü ü ü 228201 Tarago River @ Drouin West ü ü ü 228204 Dandenong Creek @ Dandenong ü ü ü ü ü 228206 Tarago River @ Neerim ü ü ü 228207 Bunyip River @ The Headworks ü ü ü 228209 Lang Lang River @ Hamiltons Bridge ü ü ü ü ü 228212 Bunyip River @ Tonimbuk ü ü ü 228213 Bunyip River @ Iona ü ü ü ü ü 228214 Diamond Creek @ Bunyip North ü ü ü 228217 Toomuc Creek @ Pakenham ü ü ü 228219 Tarago River @ Neerim South ü ü ü 228226 Stony Creek @ Shoreham ü ü ü 228228 Cardinia Creek @ Cardinia ü ü ü 229108 Yarra River Downstream Of McMahons ü ü ü 229200 Yarra River @ Warrandyte ü ü ü ü ü 229212 Yarra River @ Millgrove ü ü ü 229214 Little Yarra River @ Yarra Junction ü ü ü ü ü 229215 Woori Yallock Creek @ Woori Yallock ü ü ü 229216 Plenty River @ Mernda ü ü ü 229218 Watsons Creek @ Watsons Creek ü ü ü 229220 Don River @ Launching Place ü ü ü 229223 Diamond Creek @ Diamond Ck ü ü ü 230200 Maribyrnong River @ Keilor ü ü ü ü ü 230202 Jackson Creek @ Sunbury ü ü ü 230204 Riddells Creek @ Riddells Ck ü ü ü ü ü 230205 Deep Creek @ Bulla (Downstream Of Emu Creek Junction) ü ü ü 230206 Jackson Creek @ Gisborne ü ü ü ü ü 230208 Maribyrnong River @ Darraweit Guim ü ü ü 230209 Barringo Creek @ Barringo (Upstream Of Diversion) ü ü ü 230210 Saltwater Creek @ Bullengarook ü ü ü ü ü 230211 Emu Creek @ Clarkefield ü ü ü ü ü 230213 Turritable Creek @ Mt Macedon ü ü ü 230214 Willimigongon Creek @ Mt Macedon ü ü ü 231201 Lerderderg River @ Darley ü ü ü 231203 Pykes Creek @ Pykes Creek Reservoir ü ü ü ü ü 231204 Werribee River @ Werribee (Diversion Weir) ü ü ü ü ü 231205 Werribee River @ Melton Reservoir ü ü ü 231213 Lerderberg River @ Sardine Creek (O'Briens Crossing) ü ü ü ü ü 231225 Werribee River @ Ballan (Upstream Old Western Hwy ü ü ü ü ü 231231 Toolern Creek @ Melton South ü ü ü 232200 Little River @ Little River ü ü ü

29 Table A10: Wimmera Catchment Management Authority Station Station Name pH Tb EC TN Tp Number 415200 Wimmera River @ Horsham ü ü ü ü ü 415201 Wimmera River @ Glenorchy Weir Tail Gauge ü ü ü ü ü 415202 Mackenzie River @ Wartook Reservoir ü ü ü 415203 Mount William Creek @ Lake Lonsdale (Tail Gauge) ü ü ü 415206 Wimmera River @ Glynwylln ü ü ü 415207 Wimmera River @ Eversley ü ü ü 415214 Fyans Creek @ Lake Bellfield ü ü ü 415217 Fyans Creek @ Grampians Road Bridge ü ü ü 415246 Wimmera River @ Lochiel Railway Bridge ü ü ü

30 Appendix B – Average Trends: Catchment Management Area

31 5 pigure2fI

5 †sg„y‚sex2ge„grwix„2wexeqiwix„2e „ry‚s„siƒ „ot—l2extent2of2gwe2—re—2upstre—m2of2g—uging2sites 5

5

5

w—llee

5

5 55 5 5 5

5 5 5 5 5 5 5 5 5 5 5 xorth2gentr—l 5 5 5 5 5 5 5 5 xorth2i—st 5 5 5 5 qoul˜urn 5 5 5 ‡immer— 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 i—st2qippsl—nd 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 55 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 €ort2€hillip5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 qlenelg 5 5 5 5 5‡est2qippsl—nd 5 5 5 5 5 5 5 5 5 5 5 5 gor—ng—mite 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 555 5 55 5 5 5 5

iX’w™ms’w™HHVQV’™—d’—r™view’monitorF—prY2gwe pigure2fP †sg„y‚sex2ge„grwix„2wexeqiwix„2e „ry‚s„siƒ ere—lly2weighted2signifi™—nt2trends2in2pr

w—llee no2d—t—

xorth2gentr—l xorth2i—st

‡immer— qoul˜urn 5 ­ EHFHRT

5 ­ EHFHQT

i—st2qippsl—nd

5 €ort2€hillip

5 5 ‡est2qippsl—nd qlenelg ui‰ 5 5 hire™tion2of2™h—nge w—gnitude2of2™h—nge @GyrA gor—ng—mite S7 €ositive ­ ­ HFHPS HFHSP

CGE2HFHPS 5 ­ ­ HFIHH xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’—vg•trndF—prY2pr pigure2fQ †sg„y‚sex2ge„grwix„2wexeqiwix„2e „ry‚s„siƒ†sg„y‚sex2ge„grwix„2wexeqiwix„2e „ry‚s„siƒ ere—lly2weighted2signifi™—nt2trends2in2„ur˜idityere—lly2weighted2signifi™—nt2trends2in2„ur˜idity

w—llee no2d—t—

xorth2gentr—l xorth2i—st

‡immer— qoul˜urn ­ 5 5 EPFHVP ­ HFQVR

i—st2qippsl—nd

5 €ort2€hillip

5 5

‡est2qippsl—nd

qlenelg ­ ui‰ 5 EHFQVP hire™tion2of2™h—nge w—gnitude2of2™h—nge @x„ GyrA gor—ng—mite S7 €ositive ­ ­ HFPS

HFTP

CGE2HFPS 5 ­ ­ I xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’—vg•trnF—prY2„ur˜ pigure2fR †sg„y‚sex2ge„grwix„2wexeqiwix„2e „ry‚s„siƒ ere—lly2weighted2signifi™—nt2trends2in2ile™tri™—l2gondu™tivity

w—llee no2d—t—

xorth2gentr—l xorth2i—st ‡immer— qoul˜urn ­ PU 5 ­ PP 5

i—st2qippsl—nd

5

€ort2€hillip

­PI ­ EW

‡est2qippsl—nd qlenelg ­ ui‰ EPP 5 hire™tion2of2™h—nge w—gnitude2of2™h—nge @22sG™mGyrAm gor—ng—mite S7 €ositive ­ ­ S IS

CGE2S 5 ­ ­ PS xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’gweF—prY2ig pigure2fS †sg„y‚sex2ge„grwix„2wexeqiwix„2e „ry‚s„siƒ ere—lly2weighted2signifi™—nt2trends2in2„ot—l2xitrogen

w—llee no2d—t—

xorth2gentr—l xorth2i—st ‡immer— qoul˜urn

no2d—t— 5 ­ EHFHHW ­ EHFHIQ

i—st2qippsl—nd ­ EHFHI

€ort2€hillip ­ HFHHS ­ EHFHQP ‡est2qippsl—nd qlenelg ui‰ 5 ­ HFHRP hire™tion2of2™h—nge w—gnitude2of2™h—nge gor—ng—mite S7 @mgGvGyrA €ositive ­ ­ HFHHQ

­ HFHPS

CGE2HFHHQ 5 ­ HFHS xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’—vgEtrndF—prY2„x pigure2fT †sg„y‚sex2ge„grwix„2wexeqiwix„2e „ry‚s„siƒ ere—lly2weighted2signifi™—nt2trends2in2„ot—l2€hosphorus

w—llee no2d—t—

xorth2gentr—l xorth2i—st ‡immer— qoul˜urn ­ no2d—t— PFW ­ HFU ­ TFP

i—st2qippsl—nd

5

€ort2€hillip 5 ­ EWFW

‡est2qippsl—nd

qlenelg ­ ui‰ ERFQ 5 hire™tion2of2™h—nge w—gnitude2of2™h—nge @22gGvGyrAm gor—ng—mite S7 €ositive ­ ­ HFS

­ S

CGE2HFS 5 ­ IH xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’—vg•trndF—prY2„€ Appendix C – Average Trends: Victorian Drainage Basins

37 5 pigure2gI

5 †sg„y‚sex2h‚esxeqi2feƒsxƒ „ot—l2extent2of2˜—sin2—re—2upstre—m2of2g—uging2sites 5

5

5

5

5 55 5 5 5

5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 55 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 55 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 555 5 55 5 5 5 5

iX’w™ms’w™HHVQV’™—d’—r™view’monitorF—prY2†hf pigure2gP †sg„y‚sex2h‚esxeqi2feƒsxƒ ere—lly2weighted2signifi™—nt2trends2in2pr

IR no2d—t— V

­ HFHPW IS R

5 U P I

5 Q

5 ­ ­ T ­ EHFHQU

S

QW EHFHRV ­ EHFHRT no2d—t— ­ EHFHQU EHFHRR

QH PP PR PQ ­ EHFHQH QV PS 5 5 5 PI

5

5 QT QP QI ­ PW

5 QQ ­ 5 5 QR EHFHQQ EHFHQP

QU 5 PT PV ­ ui‰ 5 EHFHQP 5 5 hire™tion2of2™h—nge w—gnitude2of2™h—nge @GyrA S7 5 €ositive ­ HFHPS QS 5 PU ­ HFHSP

CGE2HFHPS 5 ­ ­ HFIHH xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’e‡‚g•trndF—prY2pr pigure2gQ †sg„y‚sex2h‚esxeqi2feƒsxƒ†sg„y‚sex2h‚esxeqi2feƒsxƒ ere—lly2weighted2signifi™—nt2trends2in2„ur˜idityere—lly2weighted2signifi™—nt2trends2in2„ur˜idity

IR no2d—t— V

5

IS ­ R EPFPP U P I ­ IFIQ Q 5 5 T 5 5 QW S no2d—t— ­ HFQI 5 PP QH PR PQ 5 QV PS 5 5 5 PI

5 QI 5 QT QP ­ PW 5

QQ EHFPV 5 5 QR 5 QU 5 PV PT ­ 5 ui‰ 5 5 EHFUH hire™tion2of2™h—nge w—gnitude2of2™h—nge S7 @x„ GyrA ­ €ositive ­ HFPS QS 5 PU HFQI ­

HFTP

CGE2HFPS 5 ­ ­ I xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’—wr™•trnF—prY2„ur˜ pigure2gR †sg„y‚sex2h‚esxeqi2feƒsxƒ ere—lly2weighted2signifi™—nt2trends2in2ile™tri™—l2gondu™tivity

IR no2d—t— V

­ ITH IS R U P I ­ PH 5 Q ­ IH 5 T 5 5 QW S

no2d—t— EU ­ 5 PP QH PR PQ

5

QV EIP­ PS 5

5

­ PI EIH QT QP QI ­ PW 5 5

QQ EIP 5

PV QR ­IQ

­ ­ ERH

QU ­ PV PT ­ ui‰ ET 5 ­ IH hire™tion2of2™h—nge w—gnitude2of2™h—nge EQS @22sG™mGyrAm S7 5 €ositive ­ S QS 5 PU ­ IS

CGE2S 5 ­ ­ PS xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’e‡‚g•„‚xhF—prY2ig pigure2gS †sg„y‚sex2h‚esxeqi2feƒsxƒ ere—lly2weighted2signifi™—nt2trends2in2„ot—l2xitrogen

IR no2d—t— V

no2d—t— IS R no2d—t— U P I

no2d—t— Q

5 ­

­ T ­ EHFHHW S EHFHHV QW EHFHHU

no2d—t— ­ EHFHIQ no2d—t— PP

QH PR PQ ­

­

­ QV PS ­

EHFHII PI ­ QI ­ PW EHFHHV ­ EHFHHV HFHHV QT QP EHFHIQ no2d—t— EHFHIW

QQ EHFHSH no2d—t—

5 QR no2d—t—

­

QU PV ­ PT ui‰ EHFIHV ­

­ EHFHHT ­ EHFHHR EHFHQH HFHRV hire™tion2of2™h—nge w—gnitude2of2™h—nge S7 @mgGvGyrA €ositive ­ HFHHQ QS no2d—t— PU ­ HFHII ­

­ HFHPS

CGE2HFHHQ 5 ­ HFHS xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’e‡‚gE„‚xhF—prY2„x pigure2gT †sg„y‚sex2h‚esxeqi2feƒsxƒ ere—lly2weighted2trends2in2„ot—l2€hosphorus

IR no2d—t— V no2d—t—

IS R no2d—t— U P I ­ UFH Q

5 ­ QFW ­ T ­ QFH EIFH QW S no2d—t— ­ HFS ­ PFH PP QH PR PQ

5 ­ no2d—t— QV PS ­ IFH

EIFH PI EHFV

5 QI ­ ­ QT QP PW­

QQ EIFH EQFH no2d—t—

­ HFW

QR no2d—t—

­ QU ­ IFH PV ­ PT ui‰ 5 5 hire™tion2of2™h—nge w—gnitude2of2™h—nge @22gGvGyrAm S7 ­ P €ositive ­ HFS QS IFH ­ PU ­

­ S

CGE2HFS 5 ­ IH xeg—tive ­ S7

iX’w™ms’w™HHVQV’™—d’—r™view’e‡‚g•trndF—prY2„€