Aquatic Ecology of Rivers in the Coal River Catchment · Aquatic Ecology of Rivers in the Coal River Catchment A Report Forming Part of the Requirements for State of Rivers Reporting

Aquatic Ecology of Rivers inthe Coal River Catchment

A Report Forming Part of the Requirements for State of Rivers Reporting

Tom KrasnickiAquatic EcologistWater Assessment and Planning BranchWater Resources DivisionDPIWE.

December 2003

Copyright Notice:Material contained in the report provided is subject to Australian copyright law. Other than inaccordance with the Copyright Act 1968 of the Commonwealth Parliament, no part of this reportmay, in any form or by any means, be reproduced, transmitted or used. This report cannot beredistributed for any commercial purpose whatsoever, or distributed to a third party for suchpurpose, without prior written permission being sought from the Department of Primary Industries,Water and Environment, on behalf of the Crown in Right of the State of Tasmania.

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Whilst DPIWE has made every attempt to ensure the accuracy and reliability of the informationand data provided, it is the responsibility of the data user to make their own decisions about theaccuracy, currency, reliability and correctness of information provided.

The Department of Primary Industries, Water and Environment, its employees and agents, and theCrown in the Right of the State of Tasmania do not accept any liability for any damage caused by,or economic loss arising from, reliance on this information.

Preferred Citation:DPIWE (2003) State of the River Report for the Coal River Catchment. Water Assessment andPlanning Branch, Department of Primary Industries, Water and Environment, Hobart.Technical Report No. WAP 03/11

ISSN: 1449-5996

The Department of Primary Industries, Water and Environment

The Department of Primary Industries, Water and Environment provides leadership in thesustainable management and development of Tasmania’s resources. The Mission of theDepartment is to advance Tasmania’s prosperity through the sustainable development of ournatural resources and the conservation of our natural and cultural heritage for the future.

The Water Resources Division provides a focus for water management and water development inTasmania through a diverse range of functions including the design of policy and regulatoryframeworks to ensure sustainable use of the surface water and groundwater resources; monitoring,assessment and reporting on the condition of the State’s freshwater resources; facilitation ofinfrastructure development projects to ensure the efficient and sustainable supply of water; andimplementation of the Water Management Act 1999, related legislation and the State WaterDevelopment Plan.

State Of Rivers Aquatic Ecology

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Executive Summary

This report deals with aspects of the aquatic ecology of rivers within the Coal River catchment. The firstsection provides a brief overview of the aquatic fauna found in the catchment and details the habitatrequirements and potential threats to some of the more vulnerable and threatened species. The main focus ofthe document discusses the results of a macroinvertebrate survey carried out in the Coal catchment inNovember 2000 using rapid bioassessment techniques. The Australian River Assessment System,(AusRivAS) predictive bioassessment models developed under the National River Health Program (NRHP)were used to assess the health of the Coal River catchment

Some of the major findings of this report are:

• The condition of the Coal River fish community is poor with a low diversity and abundance of nativefish, and a relative high proportion of exotic fish. Since the 1970’s, there has been a marked decrease in theabundance of both exotic and native fish, as well as in overall fish diversity. This is due to a combination offactors including the construction of instream barriers (including Craigbourne Dam), changes in flow,increased sedimentation and infestation of the riparian zone by willows.

• The Coal River is generally in ‘average’ to ‘poor’ river health according to the AusRivAS assessment.The mean ratio of observed to expected taxa (OE scores) for riffle and edgewater habitats was 0.66 and 0.70respectively, indicating a loss of up to 34% of taxa at the family level. While diversity at some sites wasmoderate to high, these communities tended to be dominated by taxa that are tolerant of habitat degradationor poor water quality, and still gave low river health scores.

• River health scores were marked by dramatic changes in species composition, particularly of taxa whichare regarded as being sensitive to various types of pollutants. A large proportion of the Coal Rivercatchment has been cleared for agricultural purposes, including sheep and cattle grazing, and cropping.Many sites showed poor water quality, with elevated turbidity and conductivity.

• Water quality alone does not dictate the macroinvertebrate community structure at a site. Habitatavailability plays an important role. Many sites on the Coal River have poor habitat quality due to increasedsedimentation, channelisation, clearance of riparian vegetation and /or infestation of the riparian zone byweeds and exotic species. In addition, the altered flow regime and consequently, changes to instream habitatavailability and water quality have impacted on the site immediately downstream of Craigbourne Dam.However, there is evidence of recovery in biotic condition with increasing distance downstream ofCraigbourne Dam. This is probably due to an increase in baseflows due to natural catchment inputs andreductions in the severity of flow regulation with increasing distance downstream.

• Implementation of better riparian management practices as outlined in the Coal Rivercare Plan,decreasing agricultural runoff, providing adequate environmental flows (especially during periods of lowflows) and effectively managing sewerage and stormwater systems have been identified as positive measuresthat could improve the health of waterways in the Coal River catchment.


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Table of Contents

Executive Summary........................................................................................................................................................... i

Table of Contents.............................................................................................................................................................. ii

Glossary of Terms and Abbreviations ...........................................................................................................................iii

1. INTRODUCTION ............................................................................................................11.1 General Description.................................................................................................................................................... 1

1.2 The Current Study ..................................................................................................................................................... 2

2. AQUATIC FAUNA ..........................................................................................................32.1 Threatened Species ..................................................................................................................................................... 3

2.2 Fish............................................................................................................................................................................... 3

3. AUSRIVAS METHODS ..................................................................................................43.1 Study Sites ................................................................................................................................................................... 4

3.2 Sampling Methods ...................................................................................................................................................... 5

3.3 Physico-Chemical and Environmental Variables .................................................................................................... 5

3.4 AusRivAS Modelling ................................................................................................................................................. 7

3.5 OE Indices ................................................................................................................................................................... 7

4. RESULTS .......................................................................................................................84.1 General faunal characteristics of the catchment ..................................................................................................... 8

4.2 Coal River Mainstream.............................................................................................................................................. 9

4.2.1 Riffles ....................................................................................................................................................................... 9

4.2.2 Edgewaters ............................................................................................................................................................. 15

4.3 Coal River Tributaries ............................................................................................................................................. 16

4.3.1 Upper Catchment Tributaries .................................................................................................................................. 16

4.3.2 Lower Catchment Tributaries .................................................................................................................................. 18

5. DISCUSSION ...............................................................................................................19

6. REFERENCES .............................................................................................................22

APPENDIX 1: TAXA LIST FOR SITES SAMPLED AS PART OF THE STATE OFRIVERS SURVEY..............................................................................................................25

APPENDIX 2: HABITAT VARIABLES AND WATER QUALITY MEASUREMENTS .......32


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Glossary of Terms and Abbreviations

Anadromous Refers to fishes which migrate from saltwater to freshwater to spawn.

AUSRIVASAustralian River Assessment System -

AWARHAustralia Wide Assessment of River Health

CatchmentThe land area which drains into a particular watercourse (river, stream or creek) and is a natural topographicdivision of the landscape. Underlying geological formations may alter the perceived catchment areasuggested solely by topography ( Limestone caves are an example of this).

DiadromousRefers to fishes that migrate freely between freshwater and saltwater in either direction

MacroinvertebrateInvertebrate (without a backbone) animals which can be seen with the naked eye. In rivers commonmacroinvertebrates are insects, crustaceans, worms and snails.

MRHIMonitoring River Health Initiative – a sub-program of the NRHP

NRHPNational River Health Program.

OE scoreA ratio comparing the number of taxa expected to occur at a site to those that were actually collected.

Riparian VegetationRiparian vegetation are plants (trees, shrubs, ground covers and grasses) which grow on the banks andfloodplains of rivers. A ‘healthy’ riparian zone is characterised by a homogeneous mix of plant species(usually native to the area) of various ages. This zone is important in protecting water quality and sustainingthe aquatic life of rivers.


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1. Introduction

This report deals with aspects of the aquatic ecology of the Coal River and associated tributaries. Itprovides a brief overview of the aquatic fauna found in the catchment and provides some informationregarding the habitat requirements and potential threats to some of the more vulnerable and threatenedspecies found in the Coal River catchment. Another section deals specifically with endangered speciesfound in the catchment and covers potential threats to the distribution and survival of each species. Themain focus of the document however, presents the results of a macroinvertebrate survey carried out in thecatchment in November 2000 using rapid bioassessment techniques. The Australian River AssessmentSystem, (AusRivAS) predictive bioassessment models developed under the National River Health Program(NRHP) were use to assess the health of the Coal River catchment. These models are comprehensive intheir development and allow a relatively rapid assessment of riverine health at specific sites along the riverand surrounding tributaries.

1.1 General DescriptionThe Coal River rises in the hills south east of Tunnack in south east Tasmania at some 580m altitude anddischarges into Pittwater to the south of Richmond (see Figure 1). It is approximately 80 km long and has acatchment area of 540 km2. From its source, the Coal River initially flows northward on dolerite and thenpredominantly on sandstone. At Baden, the river turns west, winding its way through a mixture of siltstoneand sandstone. Vegetation in this area is dominated by white gum (Eucalyptus viminalis), candlebark (E.rubida), silver peppermint (E. tenuiramis) and stringybark (E. obliqua) with an understorey of silver wattle(Acacia dealbata) pink heath (Epacris impressa), native cherry (Exocarpos cupressiformis) and bracken(Pteridium esculentum) (Davies, 1988, Gallagher, 1997)

One and a half kilometres from Lake Tiberias, the Coal River turns southward, flowing through a deeplyincised sandstone gorge for approximately 10 km. From Brandy Bottom at the southern edge of the gorgeto its point of discharge, the Coal River flows through alluvial flats interrupted occasionally by dolerite andsome basaltic silt at Richmond. In areas where the riparian vegetation has been left intact, the alluvial flatssupport a woodland of black gum (Eucalyptus ovata) and white gum over silver wattle (Askey-Doran,1993). However willow (Salix fragilis) gorse (Ulex europaeus), hawthorn (Crataegus momgyna), Africanboxthorn (Lycium ferocissimum), sweet briar (Rosa rubiginosa), blackberries (Rubus fruticosus) andCalifornian thistle (Cirsium arvense) have infested the riparian zone and adjacent streamside banks in areasthat have been cleared for agricultural purposes. Under the Coal Rivercare Plan (Ecosynthesis, 1999), largeareas of the lower Coal have been the subject of habitat rehabilitation through the removal of willows andother woody weeds and revegetation with native species.

The geological history of the Coal catchment has a major influence on the soil types and where they occuras well as the present day topography and landforms, as rock type strongly influences erosion, drainageand consequently land use activities. The soils and land capability of the Coal River catchment have beenextensively described by Holtz (1987) and Musk and De Rose (2000). Land use in the upper part of thecatchment is restricted mainly to forestry and grazing, except in the gorge where the steep slopes preventsubstantial land use.

Daley, (1999) has reviewed the land use history of the Coal Valley. The lower part of the catchment isused extensively for agricultural purposes including cropping as well as cattle and sheep grazing. In drierareas, pastures are rotated with dryland crops of barley, oats, wheat and poppies while grazing areas that reunsuited to commercial crops are often rotated with fodder crops such as turnips and oats.

The development of the South East Irrigation Scheme (SEIS) has allowed a wider range of crops to begrown than would be possible under natural dryland conditions. The Craigbourne Dam in the Coal RiverValley was constructed in 1986 and on average supplies 3000 megalitres of water each year to irrigators(RWSC, 2001). Irrigated crops in the Coal catchment include peas, brassicas, stone fruits, poppies and turf(instant lawn). Small areas of land are used intensively for market gardening, principally on alluvial sitesaround Richmond and several irrigated vineyards are found within the SEIS. However Davies et al (2002)


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has noted that since Craigbourne Dam has been operating, substantial changes in the timing and magnitudeof both high and low flows have occurred, primarily in response to storage and delivery of irrigation flows.There has been a reversal in the natural seasonal pattern, whereby there are higher summer – autumnbaseflows due to irrigation releases and reduced baseflows during winter and spring. There has also been areduction in flood size, frequency and duration.

Davies et al, (2002) has separated the lower Coal River into 10 zones based upon geomorphic factorswhich control the Coal’s character and response to natural events like flooding and anthropogenic effectsof landuse and river management. Immediately below the dam site, the river is confined to a doleritegorge, forming a narrow V-shaped valley with steep side. Further downstream, however, the valley floorgradually widens into a broader valley in which a sequence of Quaternary alluvial floodplains and terracesbegin to develop. From Campania to the river mouth, the Coal River Valley consists of a wide, flat plainup to 5 km wide.

1.2 The Current StudyThe complexity of influences on the aquatic environment means that measurement and characterisation ofthe biota is crucial to understanding anthropogenic effects on aquatic communities. This realisation has ledto the development of biological sampling of the ecology of streams to complement the more traditionalphysical and chemical monitoring. Measurement and characterisation of biological communities canreveal a more complete picture of water quality and habitat degradation because aquatic organisms showan integrated response to environmental factors (Rosenberg and Resh, 1993), reflecting the prevailingconditions at a site and the accumulation of impacts over time. Agriculture, mining, forestry andurbanisation all have the potential to affect water quality. Sites which suffer from gross nutrientenrichment or toxic pollution commonly have reduced numbers of macroinvertebrates and lower diversitiescompared with less disturbed sites. However water quality alone does not dictate the macroinvertebratecommunity structure at a site. Even a site with excellent water quality cannot support a diverse aquaticcommunity if it is devoid of suitable habitat. Loss of habitat can be due to a variety of processes includingdestruction of microhabitats, sedimentation, removal of instream woody debris and trees from the riparianzone and channelisation.

The Coal River catchment has been the subject of a number of water quality surveys concentrating largelyon water chemistry and other physical parameters (Leaman 1971, Holz 1987, Finnigan 1995, Bobbi 1997,Gallgher 1997 and Foley 2002). However there has been very little work done using biological parametersto assess the health of the catchment. Bennison (1975) used fish and macroinvertebrates to study thelongitudinal zonation of the Coal River, while Sloane (1976) examined interspecific competition betweennative and introduced fish in the Coal River and their interactions with macroinvertebrate communities.Read (1999) assessed the impact of willow removal on stream invertebrates and fish and providedinformation on catchment stream fauna and ecosystem health.

The National River Health Program was formed in 1993 by the Federal Government to provide anationally coordinated approach to assessing the ecological condition of Australia’s river systems. Amajor aim of the program was to develop and implement a standard methodology for monitoring benthicmacroinvertebrates in freshwater streams using Rapid Bioassessment (RBA) techniques, thus allowingfaster and less expensive evaluation of ecological health than would be possible using quantitativemethods. The Monitoring River Health Initiative (MRHI) in Tasmania commenced in 1994 and theprograms primary objectives were to develop predictive models to allow assessment of river health usingmacroinvertebrates as biological indicators. Over 250 sites in Tasmania were sampled in order to build theAustralian River Assessment System (AusRivAS) models.

Under the MRHI and the Australia Wide Assessment of River Health (AWARH), sampling of the CoalRiver was restricted to only 8 sites (Krasnicki et al, 2001) and was primarily aimed at the development andtesting of river health models. This report is more comprehensive, presenting the results of the State ofRiver (SOR) study, carried out in November 2000. The project’s aims are to assess the ecological health of


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32 sites, ranging from small tributaries in both the upper and lower catchment as well as the mainstreamchannel of the Coal River.

2. Aquatic Fauna

2.1 Threatened SpeciesA species is regarded as ‘endangered’ if it is in danger of extinction because its long-term survival isunlikely while the factors causing them to be endangered continue operating. A species is considered to be‘vulnerable’ if it is likely to become endangered while the factors causing to be vulnerable continueoperating. ‘Rare’ species are neither endangered nor vulnerable but are at risk due to small population size.

The current status of the green and gold frog Litoria raniformis, is ‘vulnerable’ due to its restricteddistribution and a decline in population. It is estimated that the range of L. raniformis has contracted bymore than 50% in the last 20 years (Bryant and Jackson, 1999). Wetlands, particularly in the lower reachesof the Coal catchment have been identified as key habitats for the green and gold frog. Loss of habitatthrough drainage of wetlands is perhaps the greatest single threat to this species survival. Other significantpressures include the spread of trout and a decline in water quality due to pollution by pesticides andfertilisers

2.2 FishThe fish of the Coal River catchment prior to the construction of Craigbourne Dam have been welldocumented, (Bennison, 1975; Sloane, 1976). These studies, as well as subsequent surveys by the InlandFisheries Service and DPIWE indicate that the condition of the Coal River fish community is poor, with allsites having a high proportion of exotic fish (predominantly brown trout, but redfin perch and tench havealso been recorded). Brown trout have been in the river since 1870. They form a self sustainingpopulation, although there has been some restocking in previous years to supplement natural recruitment.Rainbow trout (Oncorhynchus mykiss) are present in the Craigbourne Impoundment and have beenrecorded in the lower reaches of the Coal River (Table 1), but the rainbow trout fishery is entirelydependent on artificial stocking (French, 1994).

Subsequent surveys in the 1980’s, early 1990’s and again in 2002 have shown a marked decline in theabundance of both exotic and native fish, as well as a decrease in overall fish diversity (Table 1). Davies etal (2002) suggests that the decrease in abundance of shortfined eel (A.australis) may be due to instreambarriers, while decreases in the abundance of brown trout (S.trutta) may be attributed to several causes –reduced winter flows (for spawning and rearing), instream barriers and sedimentation of spawning and eggrearing sites.

Another factor influencing the abundance of fish in the Coal River is the presence of dense infestations ofwillows. A study on the Coal River by Read (1999) has shown that willows lead to reduced productivityand habitat quality for fish. Willow removal resulted in improved water quality and a correspondingincrease in numbers and diversity. During this study, sites in the Coal River sampled where willows havebeen removed were inhabited by brown trout, redfin perch, common jollytail (G.maculatus), spottedgalaxiid (G. truttaceus), Tasmanian smelt (R. tasmanica) and shortfined eel, while sites with willows werecharacterised by redfin perch and shortfinned eel.


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Table 1. Surveys of native and exotic fish at a number of sites in the Coal River between 1974 and 2002.

Exotics NativesYear Site Study O

. mykiss

S. trutta

P. fluviatilis

T. tinca

A. australis

G. m

aculatus

G. truttaceus

P. urvilli

R. tasmanica

01/11/74 Coal near Tunnack Bennison (site 8) 0 17 0 1 1 0 0 0 010/02/76 (River Rd) Sloane (site1) 0 88 0 5 4 0 0 0 011/02/85 IFS Survey 0 36 0 24 1 0 0 0 019/03/93 IFS Survey 0 15 0 5 0 0 0 0 009/07/02 DPIWE Survey 0 0 0 0 0 0 0 0 001/11/74 Coal at Baden Bennison (site 7) 0 6 0 24 3 0 0 0 012/02/76 (Wattle Hill Rd) Sloane (site 2) 0 15 0 3 12 0 0 0 012/02/85 IFS Survey 0 5 0 79 3 0 0 0 017/03/93 IFS Survey 0 1 0 5 3 0 0 0 026/04/94 IFS Survey 0 Pres 0 Pres Pres 0 0 0 009/07/02 DPIWE Survey 0 0 1 2 0 0 0 0 001/11/74 Coal at Brandy Bottom Bennison (site 5) 0 18 0 1 3 0 0 0 001/11/74 Coal at Craigbourne Rd Bennison (site 4) 0 6 20 5 3 0 0 0 011/02/85 Craigbourne Dam IFS Survey 0 Pres Pres 0 Pres 0 0 0 014/02/76 Coal Near Pitcairn Hill Sloane (site 3) 0 16 1 3 19 0 0 1 012/02/85 IFS Survey 0 8 2 0 18 0 0 0 017/03/93 IFS Survey 0 0 1 0 13 2 0 0 028/04/94 IFS Survey 0 Pres Pres 0 0 0 0 0 009/07/02 DPIWE Survey 0 1 0 0 1 0 0 0 023/11/95 Coal at"Stockdale" MR Survey 0 1 2 1 3 0 0 0 026/03/76 Coal at "Rosedale" Sloane (site 4) 0 5 15 1 25 0 0 0 011/2/85 IFS Survey 0 Pres Pres Pres Pres 0 0 0 Pres28/04/94 IFS Survey 0 Pres Pres Pres Pres 0 0 0 009/07/02 DPIWE Survey 0 0 3 6 2 3 0 0 001/11/74 Coal at Brown Mt Rd Bennison (site 3) 0 6 18 11 24 0 0 0 809/10/02 Coal River at Estate Rd DPIWE Survey 2 0 1 1 2 0 0 0 001/11/74 Coal at Laburnum Park Bennison (site 2) 0 1 18 10 14 0 0 0 523/11/95 Coal at Inverquarity MR Survey 0 Pres Pres 0 Pres Pres Pres 0 Pres24/2/72 Coal at Richmond IFS Survey 0 0 0 Pres 0 0 0 0 011/02/85 IFS Survey 0 Pres 0 Pres Pres 0 0 0 019/03/93 IFS Survey 0 Pres 0 Pres 0 0 0 0 026/04/94 IFS Survey 0 Pres Pres Pres Pres Pres 0 0 009/10/02 DPIWE Survey 0 0 0 0 0 0 0 1 0

3. AusRivAS Methods

3.1 Study SitesThe program was not intended to investigate point source pollution, but rather to assess the catchment’sgeneral health. Thirty-two sites across the Coal River catchment were selected as being free from obviouspoint source pollution but being otherwise as representative of the upstream reach as possible. Twelve ofthe sites were located on the mainstream of the Coal River while the remainder were scattered throughoutthe tributaries. Sampling occurred over a 1-week period from the 13 - 20 November 2000. In addition, 8sites had been previously sampled under the Australia Wide Assessment of River Health (AWARH)program in the spring of 1998 and 1999. Site locations are shown in Figure 1.


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3.2 Sampling MethodsThe sites were sampled using the Rapid Biological Assessment (RBA) method developed for the MRHIand outlined in Davies (1994) and Oldmeadow et al.(1998). Parsons and Norris (1996) have suggestedthat there is considerable redundancy among predictive models based on different habitats. Howevermacroinvertebrate samples were collected within a 100m reach of the river from riffle and edgewaterhabitats, where they were available, as different habitats are more susceptible to particular kinds ofdisturbance. Riffles are defined as areas of shallow, fast-flowing broken water usually stony or rockysubstrates. Samples were collected from riffles by disturbing 10m of the substrate to dislodge animals thatwere swept into a net by the current. The edgewater sample was collected by sweeping the net along thelateral margins of the river and in backwaters and pools which have slow currents or no flow. Aquaticplants (macrophytes), which provide additional habitat for aquatic macroinvertebrates, are often found inthese edgewater habitats and were included in the sweep sample. The contents of the net were thenemptied into a tray and live sorted in the field for 30 minutes, attempting to ensure that as broad a range oftaxa as possible was collected.

The samples were preserved in 70% ethanol and transported to the laboratory for further identification. Allmacroinvertebrates were identified to family level except in the following cases: Chironomidae (midges)were identified to sub-family level Oligochaeta (worms), Hirudinea (leeches), Acarina (mites) andTurbellaria (flatworms) were identified to order and class level. For the sake of simplicity, the term‘family’ will be used to describe identifications to these other levels.

3.3 Physico-Chemical and Environmental VariablesWater quality measurements- including temperature, pH, dissolved oxygen, electrical conductivity andturbidity were made at each site and water samples were taken for laboratory analysis of alkalinity.Observations were also made on the vegetation along the river banks (riparian zone) and aquatic habitat(substrate, depth) (Table 2). In addition detailed observations were made on a large number of habitatvariables (land use, erosion, pollution, presence of weed species etc.) to allow more descriptiveassessments of stream quality.

Table 2. Environmental variables measured at each site

Substrate Stream and Banks Map Based Physical Attributes% Bedrock % Riffle area Distance from source% Boulder % Run area Altitude (m)% Cobble % Pool area Catchment area (km2)% Pebble Stream width (m) Latitude% Gravel Bank width (m) Longitude% Sand Bank Height (m) Stream Class% Silt Stream depth (cm) Bedslope% Clay% Cover of substrate by algae Water Riparian Vegetation% Cover of substrate by detritus Temperature (oC) % Cover overhanging vegetation (shading)% Cover of substrate by silt Conductivity (µS/cm) % Cover trailing bank vegetation% Cover of substrate by moss pH % native vegetation cover

Dissolved oxygen (mg/L) % exotic vegetation coverTurbidity (NTU) Width of riparian zone (m)Alkalinity (mg/L CaCO3)


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3.4 AusRivAS ModellingThe AusRivAS model essentially predicts the aquatic macroinvertebrate fauna that would be expected tooccur at a site in the absence of environmental stress such as pollution or habitat degradation. The first stepof the model building process is classifying reference sites into groups that have similar invertebratecomposition, based on family level presence/absence data. This is done using the agglomerative clusteringtechnique, flexible unweighted pair-group arithmetic averaging (UPGMA) in the PATN program (Belbin,1994). The reference site groups from the classification are entered into the reference habitat data set and astepwise multiple discriminant function analysis (MDFA) is used to select the predictor variables used in amodel (Simpson and Norris, 2000). This procedure selects a subset of habitat variables which bestdiscriminate between the groups of sites formed from the faunal classifications. The subset of habitatvariables obtained from the stepwise MDFA is used as predictor variables for the AusRivAS model beingconstructed. The predictor variables and the reference site invertebrate classification form the foundation ofAusRivAS, allowing predictions of which taxa should be found at new sites to be made. Outputs from themodels consisted of lists of predicted taxa at each site. Their probability of occurrence at that site and ratiosof numbers of observed taxa to numbers of expected taxa (OE ratios). It is this ratio which provides ameasure of biological impairment at the tested sites (Simpson et al., 1996)

3.5 OE IndicesThe OE ratio compares the number of taxa (from the list of those predicted to occur) that actually occurredat a site with those that were expected. The OE ratios were calculated for taxa that had a probability ofoccurrence >0.49. This value is termed ‘the threshold probability’ and its use is justified on the evidencethat the occurrence of such low probability families is random and haphazard, and could make the resultstoo “noisy” (Barmuta et al, 1998). Thus not all taxa observed at a site were necessarily included in thecalculation of OE. Each site was classified into five categories or bands based on the OE ratio. Table 3presents the categories used and the OE ratio ranges for each cut off. From the table below, a site with lessthan 15 percent of the taxa expected to be present at the site is considered to be impaired to some degree.The advantage of these river health models is that not only the presence of an impact but also themagnitude can be determined for a specific site.

Table 3. River Health categories and associated OE scores for the Spring edgewater modelBandLabel

OE Scores Band Name Comments

X >1.18 Richer than Reference • More families than expected• Potentially biodiverse site• Possible mild organic enrichment

A 0.83-1.18 Similar to Reference • Index value within range of the central 80% of reference sites

B 0.48-0.82 Significantly Impaired • Fewer families than expected• Potential mild to moderate impact on water quality, habitat or both, resulting in the loss of families

C 0.13-0.47 Severely Impaired • Considerably fewer families than expected• Loss of families due to moderate to severe impact on water and/or habitat quality

D <0.13 Impoverished • Very few families collected• Highly degraded• Very poor water and/or habitat quality


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Another biotic index is incorporated into the model output to provide an insight into the nature of thedisturbance or impact at a site. OESIGNAL (Stream Invertebrate Grade Number Average Level,(Chessman, 1995) is a ratio of the observed (sampled) SIGNAL score to the expected SIGNAL score. Theindex is based on the sensitivity of macroinvertebrates to pollution. Each family of macroinvertebrates isassigned a grade according to their tolerance where a grade of 10 represents a high sensitivity to pollutionand a grade of 1 represents a high tolerance to pollution. The “observed” SIGNAL score is the sum of thegrades divided by the number of taxa collected and the “expected” score is the sum of the grades dividedby the number of taxa expected.

The OE ratio is sensitive to a wide variety of disturbances provided they result in the loss of families ofmacroinvertebrates from the habitats sampled at a site. Thus, this index should detect not only loss offamilies due to deteriorated water quality, but also loss because of physical habitat degradation. OESIGNAL weights the families by their sensitivity to water pollution. Accordingly, OESIGNAL can detectsituations where water pollution has resulted in the loss of only a few, but very sensitive, families ofmacroinvertebrates. We plotted OE versus OESIGNAL as mismatches in band allocation can providevaluable diagnostic information into the nature of the impact affecting a site. In addition, OE scores werecorrelated with numbers of families from each site.

As macroinvertebrate samples were collected from both riffle and edgewater habitats, the spring riffle andspring edgewater models were chosen as the most appropriate models for computing the indices. Eighteensites (COAL01 COAL03, COAL05, COAL10, COAL13, COAL14, COAL15, COAL16, COAL17COAL21, COAL22, COAL23, COAL27, COAL28, COAL29, COAL30, COAL31, and COAL32) weredeemed to have insufficient or unsuitable riffle habitat (Figure 1). These sites were analysed only by thespring edgewater model. The predictor variables for the spring edgewater model are distance from source,trailing bank vegetation, latitude, longitude, bedslope and stream width. The predictor variables for thespring riffle model are boulder cover, depth, latitude, longitude, bedslope and stream width (seeAppendix 2).

4. Results

4.1 General faunal characteristics of the catchmentA total of 67 taxa were identified from edgewater habitats and 60 taxa from riffle habitats. These taxarepresented all the major taxonomic groups typical of freshwater streams. Insects were the most dominantbiota, representing around 75% of the total number of taxa collected and accounting for approximately65% of the total number of individuals collected. In the edgewater habitat, the most dominant families bothin terms of distribution and abundance were Leptoceridae (caddisflies), Chironominae and Orthocladiinae(midges), Dytiscidae (predacious diving beetles) and Ceinidae (amphipods). Dominant families in rifflehabitats included Chironominae and Orthocladiinae (midges), Simuliidae (black flies), Ceinidae(amphipods) and Hydrobiidae (snails) (see Appendix 1). These results are broadly consistent with thefindings in Bennison (1975).

The distribution of macroinvertebrates reflects ecological patterns that are not unique to the Coalcatchment but reveal the nature of changes along the length of the catchment. However unlike many othercatchments, there is no general trend of increasing taxon richness towards the upper part of the catchment.This is probably a reflection of land use impacts that occur throughout the catchment. Taxa such asflatworms (Turbellaria), snails (Hydrobiidae and Physidae), damselflies (Lestidae and Coenagrionidae) andmost bugs (Hemiptera) have a cosmopolitan distribution but are more common in the lower part of thecatchment. Most families of crustaceans also show a bias towards lowland sites, except for Parameletidaeand Phreatoicidae which show a preference for upland sites. Other taxa that exhibit clear preferencesinclude Veliidae, Aeshnidae, Hydropsychidae, Conoesucidae (lowland sites) and Gripopterygidae andPolycentropodidae (upland sites).

The total number of taxa recorded per site ranged from 13 to 29 for the riffle habitat and from 7 to 30 forthe edgewater habitat. However, there was poor correlation between the ecological health of the Coal


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River as measured by OE scores and the number of taxa found at a site. The correlation was marginallybetter for the riffle habitat (r2 = 0.597, P < 0.05) than the edgewater habitat (r2 = 0343, P, 0.05). Sites thatthat had low OE scores such as Burns Creek at Rabbit Hill Road (COAL30), could still support a relativelylarge number of macroinvertebrate taxa. Conversely, some sites that were rated as good could only supporta relatively low number of families. This shows that it is not only the number of taxa alone that isimportant but the type of families and whether they are indicative of healthy or degraded rivers. If moretaxa are found at a site, but all are tolerant to degradation, then this will still yield a low river health score,and this was the case at several sites.

Of the riffle habitats that were assessed, only one (Coal River below gorge - COAL09) of the 14 sites wasclassed as ‘equivalent to reference’ (Band A) or above (Band X). Sixty-four percent of the sites sampledwere found to be ‘significantly impaired’ (Band B) and 29% of the sites were classed as ‘severelyimpaired’ (Band C). The mean O/E score for riffle habitats was 0.66. Assessment of the edgewatersamples showed a similar pattern with 9 of the 32 (or 28%) sites classed as ‘equivalent to reference’ orabove, 47% of the sites as ‘significantly impaired’ and 16% of the sites ‘severely impaired’ (Table 3). Themean OE score for edgewater habitats was 0.70. Three of the sites (Coal River at Richmond weir -COAL01; Coal at Daisy Banks - COAL02 and Coal at Fingerpost Road - COAL03) were found to beoutside the experience of the model. This indicates that one or more of the habitat variables measured atthese sites fell outside of the predictive capabilities of the model.

In cases where the riffle and edgewater assessments allocated sites to the same band, this was deemed to bethe final ‘overall’ band allocation for the site. Where there was a mismatch in band allocation from the twohabitats, then the site was allocated to the lower band. This was considered to be a more conservative andprecautionary approach. The final band allocations for each site are presented in Table 4.

4.2 Coal River Mainstream

4.2.1 RifflesAusRivAS outputs for riffle habitats rated 1 site on the Coal River as ‘above reference’ (Band X), 5 sites as‘significantly impaired’ (Band B) and 2 sites as ‘severely impaired’ (Band C). Four sites (COAL02,COAL03, COAL05 and COAL10) were not sampled due to the absence of riffles at these sites. Figures 3and 4 plot OE scores against OESIGNAL for riffle and edgewater habitats respectively, and presentpossible interpretations for sites that fall outside of the “Equivalent to Reference” A Band. This type ofplot demonstrates the usefulness of including OESIGNAL for interpretation and diagnosis.

The OE scores calculated for the Coal River riffle sites placed only one site (COAL09) within the ‘abovereference’ category (Band X). This site is located at the southern end of the gorge where the river has cutthrough the soft bedrock. There is diverse substrate composition, ranging from large boulders to finegravel and good, predominantly native riparian vegetation (Figure 2a). The steep slopes of the gorgeprovide a measure of protection from surrounding land use activities. Twenty-nine taxa were collectedfrom COAL09, making it the most diverse riffle habitat sampled. Not surprisingly, it is rated as apotentially biodiverse site. This area was declared a State Reserve in December 1980. A draftmanagement plan has been drawn up with the principal objective of protecting and conserving the naturalhabitat and landscapes of the Reserve, along with the diversity of species and communities of flora andfauna within the Reserve (P&WS, 1997).

Five sites (COAL01, COAL04, COAL06, COAL08, and COAL12) were placed in the ‘significantlyimpaired’ category (Band B). Interpretation of the outputs in Figure 3 show that the lower river healthratings are due to potential impacts other than water quality.


10

Table 4. Number of families, AusRivAS OE and OESIGNAL scores for autumn riffle and autumn edgewater models for sites in the Coal catchmentSite Code Site Name Season Edgewater

No. of taxaEdgewater

OE50EdgewaterOESignal

EdgewaterBand

RiffleNo.of taxa

RiffleOE50

RiffleOESignal

RiffleBand

Final BandAllocation

COAL01 Coal @ Richmond weir Spring 2000 18 Outside experience of the model Not SampledCOAL02 Coal @ Daisy Banks Spring 2000 34 Outside experience of the model 27 0.78 0.87 B BCOAL02 Coal @ Daisy Banks Spring 1999 23 Outside experience of the model 16 0.54 1.03 C CCOAL02 Coal @ Daisy Banks Spring 1998 20 Outside experience of the model 17 0.43 1.03 C CCOAL03 Coal River @ Fingerpost Rd Spring 2000 29 Outside experience of the model Not SampledCOAL04 Coal @ Estate Rd Spring 2000 30 0.93 0.8 A 25 0.72 0.94 B BCOAL04 Coal @ Estate Rd Spring 1999 23 0.74 0.79 B 24 0.65 0.89 B BCOAL05 Coal @ Bartonvale Spring 2000 27 0.63 0.74 B Not Sampled BCOAL06 Coal @ Pitcairn Hill Spring 2000 22 0.91 0.77 A 24 0.59 0.86 B BCOAL07 Coal d/s Craigbourne Dam Spring 2000 25 0.64 0.65 B 19 0.44 0.8 C CCOAL07 Coal d/s Craigbourne Dam Spring 1999 19 0.69 0.63 B 16 0.47 0.74 C CCOAL08 Coal @ Eldon Rd Bridge Spring 2000 19 0.6 1.14 B 21 0.6 0.88 B BCOAL08 Coal @ Eldon Rd Bridge Spring 1999 25 0.95 0.86 A 17 0.7 0.92 B BCOAL08 Coal @ Eldon Rd Bridge Spring 1998 23 1.17 0.91 A 22 1 0.99 A ACOAL09 Coal below gorge Spring 2000 21 0.94 0.9 A 29 1.15 0.96 X ACOAL10 Coal @ Wattle Hill Rd Spring 2000 26 0.86 0.89 A Not Sampled ACOAL10 Coal @ Wattle Hill Rd Spring 1999 23 0.58 1.06 B Not Sampled BCOAL10 Coal @ Wattle Hill Rd Spring 1998 24 0.96 0.83 A 22 0.86 0.91 A ACOAL11 Coal @ Tunnack Rd. Spring 2000 17 0.57 1.09 B 17 0.51 1.05 C CCOAL11 Coal @ Tunnack Rd. Spring 1999 24 0.71 1.05 B Not Sampled BCOAL11 Coal @ Tunnack Rd. Spring 1998 28 1.01 0.89 A Not Sampled ACOAL12 Coal @ New Country Marsh Rd. Spring 2000 19 1.05 0.84 A 20 0.77 0.91 B BCOAL13 Pages Ck @ Commercial Rd Spring 2000 14 0.36 0.7 C Not Sampled CCOAL14 Inverquharity Rivulet @ Prossers Rd Spring 2000 24 0.64 0.68 B Not Sampled BCOAL15 Native Hut Rt @ Estate Rd Spring 2000 22 0.56 0.67 B Not Sampled BCOAL16 Native Hut Rit u/s Campania Spring 2000 19 0.84 0.85 A Not Sampled ACOAL16 Native Hut Rit u/s Campania Spring 1998 24 0.83 0.89 A 17 0.67 0.85 B BCOAL17 White Kangaroo Rt @ Stratford Spring 2000 18 0.63 0.8 B Not Sampled BCOAL18 White Kangaroo Rt @ Mosquito Plains Spring 2000 27 1.02 0.95 A 17 0.6 0.92 B BCOAL18 White Kangaroo Rt @ Mosquito Plains Spring 1998 28 1.12 0.89 A 26 0.97 0.96 A ACOAL19 White Kangaroo Rt @ Ferniehurst Hill Spring 2000 22 0.9 0.99 A 21 0.84 0.91 B BCOAL20 White Kangaroo Rt @ Brown Mt Rd. Spring 2000 16 0.56 0.78 B 13 0.59 0.94 B BCOAL21 Broad Valley Ck. Spring 2000 13 0.46 0.68 C Not Sampled CCOAL22 Watts Gully Rt Spring 2000 17 0.66 0.92 B Not Sampled BCOAL23 Birmingham Ck nr Limekiln Hill. Spring 2000 22 0.6 1 B Not Sampled BCOAL24 Wallaby Rt d/s sewage ponds Spring 2000 22 0.8 0.82 B 14 0.45 0.79 C CCOAL25 Wallaby Rt @ Rhyndaston Rd. Spring 2000 26 0.74 0.85 B 25 0.77 0.91 B BCOAL26 Craigbourne Ck @ Link Rd Spring 2000 24 0.92 0.85 A 14 0.37 0.71 C CCOAL27 Unnamed trib of Craigbourne Ck (32) Spring 2000 28 0.82 0.89 B Not Sampled BCOAL28 Unnamed trib off Craigbourne Ck.(33) Spring 2000 7 0.37 0.92 C Not Sampled CCOAL29 Burns Ck near Eldon Br Rd. Spring 2000 22 0.6 0.86 B Not Sampled BCOAL30 Burns Ck @ Rabbit Hill Rd. Spring 2000 25 0.47 0.86 C Not Sampled CCOAL31 Hunters Swamp Ck @ Rhyndaston Rd. Spring 2000 10 0.46 0.86 C Not Sampled CCOAL32 Aarons Ck @ Stonor Rd. Spring 2000 14 0.66 0.9 B Not Sampled B


11

The Coal River at Tunnack Road (COAL11) and below Craigbourne Dam (COAL07) were assessed asbeing ‘severely impaired’ (Figures 2b-c). COAL11 has an OE value of 0.51 indicating a substantial lossof taxa (49%) relative to reference sites, whereas OESIGNAL (1.05) shows that the taxa collected weremostly sensitive taxa. Inspection of the diagnostic data shows that the taxa expected but not collected atthis site included Psephenidae (water pennies), Baetidae (mayflies), Telephlebidae (dragonflies),Eustheniidae (stoneflies) and Hydropsychidae (caddisflies). These taxa are common and are adapted tolife in strongly flowing or turbulent sections of a stream either by having a streamlined shape or byhaving some means of attaching themselves to the substrate such as claws, hooks, suckers or fixedretreats. These taxa exhibit a strong preference for large, stable rocky substrate or submerged objects suchas coarse woody debris. Assessment of the substrate composition reveals that COAL11 has up to 45%boulder and cobble cover. However, most of the substrate is covered by a layer of silt which restrictsavailable habitat for the aforementioned taxa.

The Coal River downstream of Craigbourne Dam, COAL07, (Figure 2c) also falls into the ‘severelyimpaired’ C band with losses of up to 55% of taxa. The nature and intensity of this impact is consistentwith other observations downstream of large impoundments (Davies et al, 1999; Davies and Cook, 2001;Marchant and Hehir, 2002). Davies et al, (1999) suggests that the changes in macroinvertebratecommunity composition observed at sites downstream of hydroelectric storages is associated withchanges in flow regimes rather than water quality. However the OESIGNAL score (0.8) at COAL07 maybe affected by poor water quality. At the family level, 22 taxa were predicted at (P >0.49). Of these taxa,7 were collected and included worms, mites, chironomid larvae (Orthocladiinae), crane fly larvae(Tipulidae) and leptocerid, hydropsychid and conoesucid caddis larvae. These taxa appear to be able totolerate the presence of a dam. Taxa that were predicted to occur but were not collected included anumber of coleopteran larvae (Scirtidae, Elmidae and Psephenidae), blackfly (Simuliidae) larvae,leptophlebid mayflies, gripopterygid stoneflies and a number of trichopteran larvae.

Despite the major loss of taxa and available habitat that has resulted from flow regulation by CraigbourneDam, there is some recovery in biotic condition in terms of macroinvertebrate diversity with distancedownstream. Some intolerant taxa were predicted and collected at sites further downstream.Correspondingly, there is an improvement in OE scores (Table 3) although, sites at Pitcairn Hill(COAL06), Estate Rd (COAL05) and Daisy Banks (COAL02) were still classed as ‘significantlyimpaired’ with losses between 22 to 41% of expected taxa.

Analysis of the riffles at 4 sites (COAL02, COAL04, COAL07 and COAL08) which had been previouslysampled under the AWARH (in spring 1998 and 1999), indicates river health in the lower reaches hasimproved since 1998. OE scores for COAL02 have increased from 0.43 in 1998 to 0.78 in 2000. Thisimprovement has been sufficient to elevate COAL02 from the ‘severely impaired’ C band to the upperrange of the ‘significantly impaired’ B band of biological impairment. Similarly, OE scores for COAL04increased from 0.65 in 1999 to 0.72 in 2000. Expected taxa that were not collected in 1998/1999 butcollected in 2000, included worms, mites and chironominae.

Conversely, OE scores for Coal River at Eldon Road Bridge (COAL08) immediately above theimpoundment have decreased since 1998. The magnitude of the decrease was sufficient to shift the sitefrom an ‘equivalent to reference’ (Band A) condition to a ‘significantly impaired’ (Band B) condition(Table 3). OE scores immediately downstream of Craigbourne Dam (COAL07) have remainedconsistently low (approximately 0.45) reflecting a loss of 55% of taxa at the family level.


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a) b)

c) d)Figure 2. Sites on the Coal River mainstream a) Coal River below gorge (COAL09), b) Coal River at Tunnack Rd (COAL11), c) Coal River downstream ofCraigbourne Dam (COAL07), d) Coal River at Richmond weir (COAL01).


13

19

26

20

24

04

02

11

06

0925

07

18 12

08

0.5

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

1.4

0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 1.05 1.1 1.15 1.2 1.25 1.3 1.35 1.4

Biodiverse Site

Potentially mildly enriched with organic inputs

Potential water quality problem

Potential high quality site

Impacted: either water quality, habitat or both

Potential impact other than water quality


Potentially biodiverse sites

Figure 3. Plot of OE vs OESIGNAL for riffle habitats at each site sampled under the State of Rivers study and possible interpretations for situations where the two indices place sites in different bands. The vertical and horizontal dashed lines indicate the upper and lower bounds for unimpaired (A) high quality sites

LegendX - Above ReferenceA - Equivalent to ReferenceB - ignificantly ImpairedC - Severely Impaired

OE

OE

Sign

al


14

1918

20

15

22

24

23

29

21

25 26

0928

14

04

05

07

08

16

11

3032

0617

2731 12

13

10

0.5

0.55

0.6

0.65

0.7

0.75

0.8

0.85

0.9

0.95

1

1.05

1.1

1.15

1.2

1.25

1.3

1.35

0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

OE

OE

Sign

al

Biodiverse Site

Potentially mildly enriched with organic inputs

Potential water quality problem

Potential high quality site

Impacted: either water quality, habitat or both


Potential impact other than water quality Potentially

biodiverse sites

Figure 4. Plot of OE vs OE signal for edgewater habitats at each site sampled under the State of Rivers Study and possible interpretations for situations where the two indices place sites in different bands. The vertical and horizontal dashed lines indicate the upper and lower bounds for unimpaired (A) high quality sites

LegendX - Above ReferenceA - Equivalent to ReferenceB - Significantly ImpairedC - Severely Impaired


15

4.2.2 EdgewatersAusRivAS outputs for edgewater habitats classed 5 sites as ‘equivalent to reference’ and 4 sites as‘significantly impaired’. In general, the pattern of river health for edgewaters follows that for riffles. Siteslocated above Craigbourne Dam were classed as ‘equivalent to reference’. Two exceptions were COAL08and COAL11, which were assessed as ‘significantly impaired’. These sites had high OESIGNAL scores,indicating that the impact was due to factors other than water quality. Inspection of the AusRivAS outputsshows that taxa expected but not collected at this site include Philorheithridae, Notonemouridae,Chironominae, Tanypodinae, Tipulidae, Oligochaeta and Sphaeriidae. Both of these sites have little or noriparian vegetation, which limits the amount of instream woody material that would provide habitat formacroinvertebrates. In addition, the substrate at both of these sites is dominated by silt probably caused byrunoff from gravel roads and surrounding agricultural areas (see Figure 5). It has been suggested that theedgewater fauna is affected less by impacts such as mild nutrient enrichment and smothering of habitat bysediment (Oldmeadow, 1998; Turak et al, 1999 and Bessel-Brown, 2000). However excessive sedimentationand the lack of substrate diversity are probably responsible for the low OE scores observed at these sites.

The Coal River below Craigbourne Dam is classed as ‘significantly impaired’ with losses of up to 36% oftaxa. However unlike COAL08 and COAL11, COAL07 has an OESIGNAL score of 0.65 indicating this sitemay be impacted by poor water quality. Examination of spot water quality measurements taken at the sametime as the biological samples show that the water quality parameters are similar to values found throughoutthe catchment. The only exception was pH which, at 8.31, is above that recommended by ANZECCguidelines (ANZECC, 2000). As with the riffle habitat, there has been a shift in community compositiontowards taxa that are more tolerant to changes in water quality conditions and variable flow environments.Dominant taxa in this sample include Ceinid amphipods, snails of the familiy Hydrobiidae and Planorbidaeand Caenid mayflies. Edgewater taxa immediately downstream of dams may be more susceptible to loss orreduction in habitat availability than riffle taxa due to rapidly fluctuating velocities and water levels, whichmay lead to stranding and mortality of many edgewater taxa.

As with the riffles, there is some improvement in OE scores with increasing distance downstream from thedam. The Coal River at Pitcairn Hill (COAL06) is classed as ‘equivalent to reference’ (OE = 0.91). AtCOAL05, the OE score (0.63) falls back to the level observed at COAL07. At Estate Road (COAL04), theOE score returns to 0.93, suggesting that the reason for the low score at COAL05 is due to local impacts.The three sites in the lowest part of the catchment were found to be outside the experience of the model dueto the fact that the values for the “distance from source” predictor variable for these sites lay outside therange of values found at the AusRivAS reference sites. These sites are obviously highly modified bysurrounding land use, as evidenced by a lack of riparian vegetation, the presence of exotic weed species,unrestricted stock access, bank erosion and nutrient enrichment (see separate ‘State of River’ document onwater quality in the Coal catchment). Elevated nutrient levels can cause increased growth of macrophytesthat provide an important food source and habitat for many macroinvertebrates. This can sometimes result inmacroinvertebrate communities that are more abundant or more diverse than those that would occurnaturally. Large areas of the edgewater habitat at COAL01, COAL02 and COAL03 were covered bymacrophytes which may explain why these sites, particularly COAL02 (34 taxa) and COAL03 (29 taxa), hadsome of the most diverse fauna in the catchment. However, a large proportion of these taxa (such ashydrobiid and planorbid snails, ceinid amphipods and coenagrionid damselflies) are tolerant of poor waterquality.

Temporal variation in OE scores for the five edgewater sites (COAL04, COAL07, COAL08, COAL10 andCOAL11) which had been sampled under the AWARH in 1998 and 1999 show a similar pattern to riffles. Ingeneral, sites above Craigbourne Dam (COAL11, COAL10, and COAL08) have shown a trend fordecreasing OE scores since 1998. COAL08 has shown the most dramatic decline with OE scores fallingfrom 1.17 in 1998 to 0.60 in the spring 2000 sampling round. Similarly, OE scores for COAL11 havedecreased from 1.01 in 1998 to 0.57 in 2000. The magnitude of the decrease at both these sites has beensufficient to shift the sites from Band A to the lower bounds of the ‘significantly impaired’ Band B.COAL10 experienced a sharp drop in its OE score in 1999 but recovered in spring 2000. Expected taxa thatwere collected in 1998 but not 2000 included notonemourid stoneflies, oligochaeta and midge larvae.


16

OE scores for the Coal River immediately below Craigbourne Dam have remained consistently low (0.69 in1998 and 0.64 in 2000). The OE scores for the Coal River at Estate Road (COAL04) have increased from0.74 in 1999 to 0.93 in 2000. This improvement has been sufficient to move COAL04 from the‘significantly impaired’ B band to the ‘equivalent to reference’ A band.

4.3 Coal River Tributaries

4.3.1 Upper Catchment TributariesSites on tributaries in the upper part of the catchment include Aarons Creek (COAL32), Hunters SwampCreek (COAL31), Burns Creek (COAL29 and COAL30), Wallaby Creek (COAL24 and COAL25),Craigbourne Creek (COAL26) and two unnamed tributaries off Craigbourne Creek (COAL27 and COAL28).Most of the tributaries were characterised by severe habitat degradation through clearance of riparianvegetation, erosion, sedimentation and unrestricted stock access. Where present, the riparian zone wasusually dominated by non-native species such as willows, hawthorn, blackberries and gorse. Many sites hadpoor water quality with elevated temperature, pH and conductivity levels and low levels of dissolvedoxygen, although this was probably exacerbated by the seasonal lack of flow in the tributaries. Aside fromCraigbourne Creek and the two sites on Wallaby Rivulet, the tributaries were deemed to have insufficientriffle habitat.

Wallaby RivuletTwo sites were sampled on Wallaby Rivulet. The upper site on Rhyndaston Road (COAL25) was classifiedby the spring riffle and edgewater models as ‘significantly impaired’ (Band B), with OE scores of 0.77 and0.74 respectively. Whilst the fauna was diverse with 25 (riffle) and 26 (edgewater) taxa collected, it wasdominated by ceinid amphipods, phreatoicid isopods and hydrobiid snails. OE and OESIGNAL scoresindicate that the impairment at this site is more related to habitat degradation rather than poor water quality.COAL 25 lies within a highly eroded gully with steep banks up to 8 metres above the stream bed. (Figure5a). The land on both sides has been cleared for grazing and the sparse riparian vegetation is dominated byexotic species. The lower site is below the sewage pond discharge point (Figure 5b), and shows a markeddeterioration in water quality. Electrical conductivity exceeding 1200 µs/cm was recorded from this site,although this is still below levels likely to have an impact on fauna (Metzling, 1993). Nevertheless, thechanges that occur between COAL25 and COAL24 are dramatic both in terms of number of taxa collectedand taxa composition. A number of taxa collected from COAL25 were absent from COAL24. This isparticularly evident in the riffle habitat where only 14 taxa were collected. The OE score for the rifflehabitat was 0.45, indicating a loss of more than half of the expected taxa. The OESIGNAL score of 0.79indicates that this impairment is due to poor habitat and/or water quality.

Craigbourne CreekOne site was sampled on Craigbourne Creek (COAL26) as well as two minor, unnamed tributaries (COAL27and COAL28). The edgewater habitat was assessed as ‘equivalent to reference’ with an OE score of 0.9 andan OESIGNAL score of 0.85, although this is not reflected in the physical habitat which shows significantsigns of disturbance. Erosion, runoff from pasture and stock access to all parts of the creek have increasedturbidity levels within the stream and deposited a layer of silt over the substrate. There is also evidence ofnutrient enrichment with algae, macrophytes and aquatic weeds present throughout. Median Total Nitrogen(TN) was in excess of 500 µg/L (Foley, 2003). Consequently the taxa found at this site were generallytolerant of poorer water quality. However, the greatest impact on the site is the presence of a damapproximately 150 metres above the sampling site. Flow downstream of the dam has been reduced to suchan extent that there was barely sufficient habitat to collect a riffle sample. This may explain the discrepancyin OE scores for the edgewater (0.9) and riffle (0.37) habitats.


17

a) b)

c) d)

Figure 5. Sites on the Coal River tributaries a) Wallaby Rivulet at Rhyndaston Rd. (COAL25), b) Wallaby Rivulet downstream sewage ponds (COAL24),c) Burns Creek near Eldon Road Bridge (COAL29), d) White Kangaroo Rivulet at Mosquito Plains (COAL18).


18

Only edgewater samples were collected from the two tributaries of Craigbourne Creek. COAL27 wasassessed as significantly impaired with an OE score of 0.82. Although COAL27 was particularly diverse(28 taxa) only 9 of the 11 taxa predicted by the model were collected. This discrepancy highlights therequirement for informed scrutiny of the outputs. In this case, an unexpected assemblage of families wascollected. This is evident in the low number of key families and AusRivAS predicted families inproportion to the total number of families collected. The taxa collected were indicative of mild nutrientenrichment and included diving beetle larvae (Dytiscidae), ceinid amphipods and damselflies of thefamily Lestidae.

The lack of flow at COAL28 has reduced this creek to little more than a series of intermittent pools. Thecreek dries up completely approximately 200 metres above the sampling site. Water quality at this sitewas poor at the time of sampling with elevated temperature and conductivity, high pH and very lowdissolved oxygen (3.5 mg/L). Only 7 taxa, including chironominae, mosquito larvae, leptocerid caddisflyand diving beetle adults and larvae were collected at COAL28. The OE score for this site was 0.37indicating a loss of over 60% of taxa at the family level.

Burns CreekTwo sites were sampled on Burns Creek. The upper site at Rabbit Hill Road (COAL30), despite having arelatively diverse fauna (25 taxa) was classified by the spring edgewater model as ‘severely impaired’(OE = 0.46). The lower site near Eldon Road Bridge Road (COAL29) was in better condition with an OEscore of 0.6. Both sites had an OESIGNAL score of 0.86, indicating the impact is related to a factor otherthan water quality. As with other tributaries in the upper catchment, Burns Creek is affected byagricultural activities. Both sites showed signs of extreme disturbance with riparian zones cleared to thewater’s edge (Figure 5c) and cropping and grazing extending throughout the area. The streambed iscomposed of fine substrate and overlaid with a fine layer of silt and algae. This has been compounded bythe prolific growth of macrophytes and other aquatic weeds, which cover up to 60% of the streambed andhave contributed to sediment build up at these two sites.

4.3.2 Lower Catchment TributariesTributaries assessed in the lower part of the catchment include Pages Creek (COAL13), InverquharityRivulet (COAL14), Native Hut Rivulet (COAL15 and COAL16), White Kangaroo Rivulet (COAL17,COAL18, COAL19 and COAL20) Broad Valley Creek (COAL21) and Watts Gully Rivulet (COAL22)

White Kangaroo RivuletFour sites were assessed on White Kangaroo Rivulet. The pattern of OE scores down the length of theriver reflect ecological changes that are closely related to land use, water quality and physical habitatcharacteristics. The site at Brown Mountain Road (COAL 20), in the upper reaches of White KangarooRivulet, was assessed by the spring edgewater model as ‘significantly impaired’ with an OE score of 0.56.Only 5 of the 11 taxa predicted to occur at this site were collected. This is probably due to the lack offlow and the small size of the rivulet at this point. The low OESIGNAL score (0.80) suggests somepollution due to runoff from surrounding land and direct stock access in to the stream. Furtherdownstream, there is improvement in the biotic condition of the rivulet with OE scores increasing to 0.9at Ferniehurst Hill (COAL19) and 1.02 at Mosquito Plains (COAL18). Both sites have predominantlynative vegetation consisting primarily of Eucalyptus and Acacia although there is some intrusion byblackberries, willow and hawthorn (Figure 5d). At “Stratford” (COAL17), just above the confluence withthe Coal River, there is noticeable disturbance of the riparian habitat. The surrounding land has beencleared for grazing, and there is evidence of stock access into the rivulet, which has caused erosion of thebanks in some areas. There is a corresponding decrease in the OE score (0.56) for this site which is at thelower end of the ‘significantly impaired’ (B band) river heath category.

The pattern of river health for the riffle habitat follows that for edgewaters. COAL17 had insufficientriffle habitat due to the presence of a weir approximately 150 metres above the sampling site. Theremaining three sites were assigned to the same band as for the edgewater model except for COAL18which was just under the threshold for the ‘equivalent to reference’ band.


19

Native Hut RivuletNative Hut Rivulet at Estate Road (COAL15) and upstream of Campania (COAL16) are both subject toagricultural impacts. The land has been cleared to the waters edge and the sparse riparian vegetation isdominated by pasture grasses or exotic species such as willow, hawthorn and briar rose. Erosion isevident at the sites due to lack of vegetation to bind the soil and banks, and unrestricted stock access.Erosion as well as runoff from cleared land has contributed to the excessive sedimentation observed atboth sites, which has blanketed the substrate and limited the amount of habitat for macroinvertebrates. Inaddition, electrical conductivities of 953 µS/cm and 1234µS/cm were recorded at COAL15 and COAL16respectively. Despite both sites having a similar fauna in terms of abundance and communitycomposition, COAL15 was assessed as being significantly impaired while COAL16 was assessed asequivalent to reference (Table 3). Inspection of the diagnostic data shows that 3 predicted taxa – marshbeetles (Scirtidae), biting midges (Ceratopogonidae) and leptophlebiid mayflies were collected fromCOAL16 but not at COAL15.

5. DiscussionMeasurement and characterisation of macroinvertebrate community structure has been crucial to theunderstanding the anthropogenic impacts on the Coal River. The 32 sites selected for sampling in thisstudy have exhibited a wide range of impacts - from a near pristine site in the Coal River gorge(COAL09) to highly degraded and extremely depauperate sites on tributaries impacted by agriculturalactivities. The Coal River and associated floodplains and riparian zones have been extensively modifiedsince European settlement (Ecosynthesis, 1999). Natural patterns of water quality and habitat changehave been obscured by the impact of agriculture throughout the catchment, as well as the impact of flowregulation by Craigbourne Dam. This has ensured that there is no general trend of decreasing taxonrichness from the upper to the lower reaches of the catchment.

Rivers throughout the Coal River valley are generally in poor condition. Of the 32 sites assessed usingthe AusRivAS river health methodology, only 3 sites (9 %) were found to be ‘equivalent to reference’ (Aband). Eighteen sites (56%) were found to be ‘significantly impaired’, 9 sites (28%) were ‘severelyimpaired’ and 2 sites (6%) were outside the experience of the model. Assessment of these latter sites willonly be possible by enlarging the reference site database that is used by the model, to include referencesites with similar habitat features (Simpson, 2000).

In general, the health of the riffle habitat was poorer than that of the edgewaters. Of the 13 sites forwhich riffle and edgewater AusRivAS outputs were obtained, the final band allocation for 9 of the siteswas determined by the lower OE scores that were recorded for the riffle habitat. This is consistent withfindings in other catchments (Krasnicki, 2002). It has been suggested (Oldmeadow, 1998; Turak et al.,1999 and Bessel-Brown, 2000) that edgewater fauna is affected less by impacts such as nutrientenrichment and sedimentation. It is clear that habitats vary in their susceptibility to different types ofimpacts, and the use of the most precautionary approach, as outlined in Barmuta et al. (1998) is warrantedwhen combining assessments across habitats.

Interpretation of AusRivAS outputs has shown that the macroinvertebrate community at many sites areimpacted by poor habitat, poor water quality, or both. Physical degradation of the stream habitat is oftencompounded by chemical and organic pollution. Nutrients, fertilisers, pesticides and herbicides are majorpollution sources in many rural areas. In urban areas chemical pollution results from storm water run-off,industrial spills, leaching or overloaded sewers and leaching of wastes from disposal sites. Water qualitydegradation tends to accumulate along a river’s length, so that damage suffered at one point iscompounded further downstream by additional impacts. A number of water quality issues are ofpotential concern in the Coal River including pH, dissolved oxygen, turbidity, conductivity and nutrients.Changes in pH affect the concentration and toxicity of chemical substances ad the ionic and osmoticbalance of aquatic organisms. The waters of the Coal River are slightly alkaline with pH levels typicallybetween 7.0 and 8.5. The highest pH levels were recorded from Inverquharity Rivulet at Prossers Road(8.64), the Coal River below Craigbourne dam (8.31) and White Kangaroo Rivulet at Ferniehurst Hill(8.31). These sites approach the upper limit of environmental guidelines for fish.


20

Most aquatic organisms become stressed when concentrations of dissolved oxygen fall below 6.0 mg/L(ANZECC, 1992). DO levels in the faster flowing reaches of the Coal River appear to be adequate,however a few sites in smaller tributaries were reduced to isolated pools in which dissolved oxygen levelsfell below critical levels (eg Watts Gully Rivulet - 3.7 mg/L; and a tributary off Craigbourne Creek - 3.5g/L). Not surprisingly these sites were assessed as ‘significantly’ to ‘severely’ impaired due to the lowdiversity of fauna collected at both sites.

The Coal River valley had been identified as a “high risk” area for salinisation. Overall, salinity levels inrivers and streams in the valley are caused by naturally high salinity levels in soils and groundwater, andthis is potentially exacerbated by irrigation practices (Davies, 2002). Inverquharity Rivulet at ProssersRoad, Native Hut Rivulet upstream of Campania and lower Wallaby Rivulet all had electricalconductivity that exceeded 1000 µS/cm, although this is below levels likely to have an effect on instreamfauna (Metzling, 1993).

Whilst these measures of water quality give some indication of the aquatic health of a particular site, theydo not give insight into the long-term biological condition of a stream. The results of this study show thatland use, and impacts on the condition and extent of the riparian zone and instream habitat are stronglyinfluential on macroinvertebrate community composition and river health. Habitat degradation wasevident at many sites throughout the Coal catchment, and included bank erosion, instream sedimentation,channelisation,, the presence of exotic weed species in the riparian zone, extensive stock access and landcleared for cropping and grazing.

The quality of aquatic habitat is closely linked to riparian vegetation (Cummins, 1993). The type ofvegetation along the banks can strongly influence stream morphology, including width and cross-sectional shape, by binding bank material and preventing bank slumping (Bessell-Browne, 2000).Vegetation type also affects the extent of trailing bank vegetation, the interception of sediment fromrunoff, water temperature and primary production through shading, and the deposition of allochthanousorganic material. Riparian vegetation can contribute large woody debris, branches or whole trees to thestream, and this can form a major structural component of the stream morphology, and serve as a linkbetween terrestrial and aquatic systems (Hilderbrand et al. 1997). Degradation of the riparian zone oftenleads to edgewater habitat destruction and loss of the natural buffer against contamination. This iscommon in rural areas of the Coal where the natural riparian vegetation has been completely altered orremoved. Sediment from bank erosion, often exacerbated by unrestricted stock access, runoff fromcleared land and from gravel roads has blanketed the stream and limited habitat availability at many sites.This is often compounded by the intrusion of willows into the stream and the prolific growth ofCumbungi (Typha latifolia) and other aquatic weeds which have responded to increased light levels instreams and contributed to sediment build up.

Despite widespread habitat degradation, there is a marked recovery in macroinvertebrate diversity andcommunity composition at sites in which patches of remnant native riparian vegetation are still present.This is significant, as it shows that there is substantial potential for recovery where reaches are subject torehabilitation activities. Under the Coal Rivercare Plan (Ecosynthesis, 1999), a number of reaches havebeen targeted for removal of willows and other woody exotics. Where applicable, streamside zones willalso be fenced to manage stock access. However, removal of willows without further restoration goals isnot ecologically sound in terms of riparian-stream linkages (Read, 1999). Rehabilitation of reaches withnative riparian vegetation is a natural and important progression following willow removal, and theresults from this study suggest that where this occurs, there will be substantial improvements in riverinehealth.

Implementation of the Rivercare Plan will allow an opportunity for monitoring the environmental benefitat sites at which habitat rehabilitation is taking place. One such site is the Coal River at Estate Road(COAL04) where willows were removed in 1999. This site was sampled in 1999 and again in 2000, butmonitoring over the medium to long-term will be required before any environmental benefit is observed.Short-term variation in the OE score at COAL04 and other sites which have been sampled on a number ofoccasions since 1998 (Table 3) is more likely due to inter-annual differences in the fauna at a site,


21

variability and instability of organic inputs or changes associated with the flow regime downstream ofCraigbourne Dam.

The altered flow regime and subsequent changes to instream habitat availability and water quality haveimpacted on the site immediately downstream of Craigbourne Dam. However, this study shows there isrecovery in biotic condition with increasing distance downstream of Craigbourne Dam. This is probablydue to an increase in baseflows due to natural catchment inputs and reductions in the severity of flowregulation with increasing distance downstream.

Implementation of better riparian management practices, decreasing agricultural run-off, providingadequate environmental flows especially during periods of low flow and effectively managing sewerageand stormwater systems have been identified as measures that could improve the health of waterways inthe Coal catchment. Such measures will greatly benefit not just macroinvertebrate communities but thewhole stream ecosystem.


22

6. ReferencesANZECC (2000) Australian Water Quality Guidelines for Fresh and Marine Waters. Australian and NewZealand Environment and Conservation Council, Canberra.

Askey-Doran M. (1993). Riparian Vegetation in the Midlands and Eastern Tasmania. Department ofEnvironment and Land Management - Parks and Wildlife Service, Hobart Tasmania.

Barmuta, L.A.,Chessman, B.C. and Hart, B.T. (1998) Interpreting the outputs from AUSRIVAS.Occasional Paper Series No. 02/98. (LWRRDC: Canberra)

Belbin, L. (1994) PATN Pattern Analysis Package. CSIRO Division of Wildlife and RangelandsResearch, Canberra.

Bennison G.L. (1995). Classification of the Coal River in south east Tasmania. Honours Thesis,University of Tasmania.

Bessel-Browne, T. (2000). Environmental Health of streams in the Yarra River catchment. EPAPublication 682, Environmental Protection Agency, Melbourne.

Bobbi C 1997. Report on a bloom of the blue-green algae, Anabaena circinalis at Craigbourne Dam,Colebrook (June - September, 1997). DPIWE, Report Series WRA 97/10. Hobart.

Bryant, S. L. and Jackson, J., (1999). Tasmania’s Threatened Fauna Handbook: what, where and how toprotect Tasmania’s threatened animals. Threatened Species Unit, Parks and Wildlife Service, Hobart

Chessman, B.C. (1995) Rapid assessment of rivers using macroinvertebrates: a procedure based onhabitat -specific sampling, family level identification and a biotic index. Australian Journal of Ecology,Vol. 33, pp.122-129.

Cummins K.W., (1993) Riparian stream linkages: Instream Issues, in Ecology and Management ofRiparian zones in Australia. (Eds.S.E. Bunn, B.J. Pusey and P. Price). LWRRDC Occasional Paper SeriesNo. 05/93

Daley, E, (1999), Land Cover, Climate and Stream Flow in the Coal River Catchment, 1965-1997. BScHonours Thesis. School of Geography and Environmental Studies, University of Tasmania, Hobart.

Davies (1994), National River and Management program Monitoring River Health Initiative: River Bio-assessment Manual. Commonwealth Environmental Protection Agency, Canberra.

Davies, J. (1998). Land Systens of Tasmania – region 6: south East and Midlands. Department ofAgriculture, Tasmania.

Davies, P.E., Cook, L.S.J. and McKenny C.E. (1999) The influence of changes in flow regime on aquaticbiota and habitat downstream of hydro electric dams and power stations in Tasmania. Hydro TechnicalReport No. 95/034. Hobart Tasmania, 128pp.

Davies, P.E. and Cook, L. (2001). Gordon River macroinvertebrate and aquatic mammals assessment.Appendix 7. Basslink Integrated Impact Assessment Statement. Potential effects of changes tohydropower generation. Freshwater Systems, Hobart. 141pp

Davies, P.E., Crawford, C.M., Wells, F.A., Dunstan, P and Mitchell, I.M. (2002) Environmental flowassessment of the Lower Coal River and Pitt Water Estuary. Freshwater Systems and the TasmanianAquaculture and Fisheries Institute, Hobart 203pp

Ecosynthesis (1999). Coal Rivercare Plan. Coal Valley Landcare Group. Tasmania


23

Finnigan, J.J. (1995). Salinity assessment in Tasmanian irrigation schema and regional areas. DPIF FinalReport, Hobart Tas. 43 pp.

French, G. (1994). Tasmanian Trout Waters. Greg French, Tasmania

Foley, A.J., (2002). Water Quality of Rivers in the Coal Catchment in State of Rivers Report for the CoalRiver Catchment DPIWE, Report Series WAP 03/11. Hobart.

Gallagher, S (1997). Coal River Catchment Natural Resource Assessment. Report to the Coal RiverCatchment Committee, Tasmania.

Hilderbrand, R.H., Lemly, A.D., Dolloff, C.A. and Harpster, K.L. (1997). Effects of large woody debrisplacement on stream channels and benthic macroinvertebrates. Canadian Journal of Aquatic Sciences, 54,931-939

Holz G.K. (1987). Soils of Part of the Lower Coal River Valley, Tasmania. Chemistry and Soils Section,Dept of Agriculture, Tasmania.

Krasnicki, T., Pinto, R.D. and Read, M.G. (2000). Australia Wide Assessment of River Health; TasmaniaProgram Final Report. Department of Primary Industries, Water and Environment, Hobart, TechnicalReport No. WRA 01/2001.

Leaman, D.E. (1971). The geology and Ground water Resources of the Coal River Basin. UndergroundWater Supply Paper No. 7. Tasmania department of Mines Hobart, Tasmania.

Marchant, R. and Hehir, G. (2002) The use of AUSRIVAS predictive models to assess the response oflotic macroinvertebrates to dams in south-east Australia. Freshwater Biology, 41, 1033-1050.

Metzling, L. (1993) Benthic Macroinvertebrate structure in streams of different salinities. AustralianJournal of Marine and Freshwater Research, Vol. 44: 335-351

Minshall, G. W. (1984) Aquatic Insect Substrate Relationships. Ecology of Aquatic Insects. Edited by V.H. Resh and A. M. Rosenberg. Praeger. pp358-400

Musk R.A. and De Rose R.C. (2000) Land Capability Survey of Tasmania. Derwent Report. Dept. ofPrimary Industries, Water and Environment, Tasmania.

Oldmeadow, D., Krasnicki, T. & Fuller, D. (1998) Monitoring River Health Initiative. Department ofPrimary Industry and Fisheries, Hobart. Technical Report No. WRA 98/03.

Parsons, M. and Norris, R. H. (1996) The effect of habitat specific sampling on biological assessment ofwater quality using a predictive model. Freshwater Biology, 36: 419-434

P&WS. (1997) Coal River Gorge Nature Reserve – Draft Management Plan, 1997. Parks and WildlifeService, Dept of Environment and Land Management.

Read, M., (1999). Comparison of in-stream faunas under different riparian types. PhD Thesis, Universityof Tasmania, Hobart.

Simpson, J., Norris, R., Barmuta, L., and Blackman, P. (1996) AUSRIVAS- National River HealthProgram - User Manual. CRC for Freshwater Ecology, University of Canberra.

Simpson, J.C. and Norris, R.H. (2000) Biological assessment of river quality: development ofAUSRIVAS models and outputs. In: Assessing the Biological Quality of Freshwaters: RIVPACS andOther Techniques (Eds J.F.Wright, D.W. Sutcliffe & M.T.Furse), pp. 125-142. Freshwater BiologicalAssociation, Ableside, U.K.


24

Sloane RD (1996). Interrelationships between native and introduced fish in two rivers in south-eastTasmania. Honours Thesis, University of Tasmania

Turak, E., Hose, G., and Waddell, N., (2000), Australia-Wide Assessment of River Health: New SouthWales Bioassessment Report (NSW Final Report), Monitoring River Heath Initiative Technical ReportNo 2a, Commonwealth of Australia and NSW Environment Protection Authority, Canberra and Sydney.


25

Appendix 1: Taxa List for sites sampled as part of the State of Riverssurvey


26

Order Platyhelminthes Mollusca Mollusca Mollusca Mollusca Mollusca Mollusca Hirudinea Oligochaeta AcarinaFamily Turbellaria Hydrobiidae Lymnaeidae Ancylidae Planorbidae Physidae Spaeriidae Acarina

Sub FamilySite Code Site Name Taxa code IF999999 KG029999 KG059999 KG069999 KG079999 KG089999 KP039999 LH999999 LO999999 MM999999

Edgewater/ Riffle E R E R E R E R E R E R E R E R E R E RCOAL01 Coal @ Richmond weir 1 12 1 5 8COAL02 Coal @ Daisy Banks 2 3 18 20 3 11 1 4 2 18 8 1COAL03 Coal River @ Fingerpost Rd 1 49 20 1 2COAL04 Coal @ Estate Rd 2 5 22 11 3 9 4 8 7COAL05 Coal @ Bartonvale 7 20 2 1 1 3COAL06 Coal @ Pitcairn Hill 1 7 15 1 8 1 3 3 2 4 2 3COAL07 Coal d/s Craigbourne dam 3 16 24 34 25 12 6 12 1 3 4 3 5 2COAL08 Coal @ Eldon Rd Bridge 2 7 3 1 4 1 6COAL09 Coal below gorge 2 11 3 1 12 2 5 4 15 4COAL10 Coal @ Wattle Hill Rd 13 8 4COAL11 Coal @ Tunnack Rd. 1 6 79 126 17 8 2 3COAL12 Coal @ New Country Marsh Rd. 1 2 1 18 17 7 20 11COAL13 Pages Creek @ Commercial Rd 27 13 51COAL14 Inverquharity Rivulet @ Prossers Rd 1 17 28 2COAL15 Native Hut Rit @ Estate Rd 6 12 4 1 2COAL16 Native Hut Rit u/s Campania 10 3 2COAL17 White Kangaroo Rit @ Stratford 2 25 4 30 5COAL18 White Kangaroo Rt @ Mosquito Plains 1 1 4 12 2 2 1 2 10 10 1COAL19 White Kangaroo Rt @ Ferniehurst Hill 9 1 1 2 19 23 3COAL20 White Kangaroo Rt @ Brown Mt Rd. 2 1 2COAL21 Broad Valley Ck. 2 57 12 2COAL22 Watts Gully RtCOAL23 Birmingham Ck near Limekiln Hill. 4 11 3 7COAL24 Wallaby Rt d/s sewage ponds 3 26 17 4 8 1COAL25 Wallaby Rt @ Rhyndaston Rd. 7 49 71 2 4 4 8 9 3 10 22 15 27 1COAL26 Craigbourne Ck @ Link Rd 1 2 2 4 1 1 6COAL27 Unnamed trb of Craigbourne Ck. 4 1 4 2COAL28 Unnamed trb off Craigbourne Ck.COAL29 Burns Ck near Eldon Br Rd. 34 2 1 3COAL30 Burns Ck @ Rabbit Hill d. 2 3 1 9COAL31 Hunters Swamp Ck @ Rhyndaston Rd. 2 49 12COAL32 Aarons Ck @ Stonor Rd. 3 77 3


27

Order Amphipoda Amphipoda Amphipoda Isopoda Isopoda Isopoda Decapoda Coleoptera Coleoptera Coleoptera Coleoptera Coleoptera Coleoptera ColeopteraFamily Ceinidae Eurisidae Parameletidae Phreatoicidae Janiridae Oniscidae Atyidae Dytiscidae Dytiscidae Gyrinidae Gyrinidae Hydrophilidae Staphylinidae Scirtidae

Sub Family Adults Larvae Adults LarvaeCode OP029999 OP039999 OP069999 OR039999 OR189999 OR259999 OT019999 QC09999A QC09999L QC109999 QC10999L QC119999 QC189999 QC209999

E R E R E R E R E R E R E R E R E R E R E R E R E R E RCOAL01 131 20 1 3 1COAL02 97 51 4 5 2 9 5 4 1 2 3COAL03 42 2 2 6 5 5 2COAL04 40 17 4 14 3 7 3 17 6 10 4 1 3COAL05 58 41 1 17 3 6 1COAL06 34 21 1 4 1 2 2 16COAL07 122 60 2 11 2 5 5 2COAL08 42 5 3 18 12 5 1COAL09 30 4 33 9 2 1 2COAL10 36 2 1 4 1COAL11 29 32 4 11 7 6 14 9COAL12 3 2 4 2 3 1 4 28 1 1 5COAL13 21 9 12 7COAL14 165 1 16 13 8COAL15 33 2 3 8 39 2COAL16 52 1 18 1COAL17 28 1 2 20COAL18 31 5 4 12 2 1 1 1COAL19 4 1 1 2 33 22 2 29COAL20 5 1 6 27 15COAL21 12 17COAL22 8 2 62 2COAL23 136 21 16 3 3 2COAL24 77 1 3 1 3 12 1 1COAL25 165 215 8 19 6 76 15 10 3 10 1 1COAL26 15 6 10 7 18 21 5 2 1COAL27 35 2 15 21 1COAL28 6 9 3COAL29 40 2 2 15COAL30 63 2 18 72 1 2 4COAL31 52 73 1COAL32 1 62 28 3


28

Order Coleoptera Coleoptera Coleoptera Coleoptera Diptera Diptera Diptera Diptera Diptera Diptera Diptera Diptera Diptera DipteraFamily Elmidae Elmidae Psephenidae Curculionidae Tipulidae Dixidae Culcidae Ceratopogonidae Simuliidae Athericidae Stratiomyidae Sciomyzidae Chironomidae Chironomidae

Sub Family Adults Larvae Diamesinae PodonominaeCode QC34999A QC34999L QC379999 QCAN9999 QD019999 QD069999 QD079999 QD099999 QD109999 QD229999 QD249999 QD459999 QDAB9999 QDAD9999

E R E R E R E R E R E R E R E R E R E R E R E R E R E RCOAL01 1 14COAL02 3 16 6 1 2 13COAL03 1 12COAL04 11 3 1 1 3 45COAL05COAL06 1 1 26COAL07 1COAL08 1 3 1 1 2 7COAL09 22 4 2 2 2 1 19 1COAL10 3COAL11 14 8 2 35 31COAL12 1 1 1 1 5 7 3COAL13COAL14 1 2 5COAL15 6COAL16 5COAL17COAL18 1 3 71COAL19 28 4 2 3 1 1 2 2 98 1 4COAL20 3 2 2 66 3COAL21 2 4COAL22 1 1 1COAL23 2 2 1COAL24 1 4 2 1COAL25 4 2 1 6 1COAL26 6 2 1 2 4 1 16COAL27 5 1 3COAL28 18 1COAL29 3COAL30 3 9COAL31 1COAL32 4


29

Order Diptera Diptera Diptera Ephemeroptera Ephemeroptera Ephemeroptera Ephemeroptera Hemiptera Hemiptera Hemiptera Hemiptera Hemiptera HemipteraFamily Chironomidae Chironomidae Chironomidae Baetidae Oniscigastridae Leptophlebiidae Caenidae Veliidae Gerridae Corixidae Naucoridae Notonectidae PleidaeSub Family Tanypodinae Orthocladiinae Chironominae

Code QDAE9999 QDAF9999 QDAJ9999 QE029999 QE039999 QE069999 QE089999 QH569999 QH579999 QH659999 QH669999 QH679999 QH689999E R E R E R E R E R E R E R E R E R E R E R E R E R

COAL01 3 1 15COAL02 11 13 5 78 2 1 9 29 19 2 13COAL03 49 9 9 15 1 2 3COAL04 10 2 67 1 1 8 41 27 4 2 7 1COAL05 2 7 2 10 5 7COAL06 20 17 29 5 2 6 25 15 9 1 20COAL07 8 4 63 9 27 3 10 3 3 1COAL08 1 158 86 2 17 22 7 16 13 2 2COAL09 2 1 3 38 45 3 2 5 11 18 2 1 68COAL10 2 23 3 12 19 14 2 10 1 1 9COAL11 57 22 14 10 7 9COAL12 5 3 45 17 15 7COAL13 1 3 5 14COAL14 1 4 25 4 7 14 30COAL15 2 43 13 31 3COAL16 13 9 21 10 25 15 3 1COAL17 6 52 45 6 1 6COAL18 3 8 19 42 7 1 24 6 1 4COAL19 8 5 28 7 1 17 66 21 4 1COAL20 5 12 17 68 3 6 1 20 7 2COAL21 1 61COAL22 11 2 62 9 1COAL23 2 1 10COAL24 3 8 38 71 86 1 25 4 49 1COAL25 3 70 13 2 1 1 1 27 5COAL26 13 59 10 1 1 1 24 14 1 2COAL27 11 9 8 3 10 2 5 1COAL28 56COAL29 10 2 1 4 61 7 1 1COAL30 1 20 13 1 2 23 55 8COAL31 5 1COAL32 2 16


30

Mecoptera Lepidoptetra Neuroptera Odonata Odonata Odonata Odonata Odonata Odonata Plectoptera Plecoptera Trichoptera TrichopteraNannochoristidae Pyralidae Sisyridae Coenagrionidae Lestidae Telephlebiidae Gomphidae Synthemistidae Hemicorduliidae Gripopterygidae Notonemouridae Hydrobiosidae Hydroptilidae

Code QK019999 QL019999 QN059999 QO029999 QO059999 QO219999 QO139999 QO239999 QO309999 QP039999 QP049999 QT019999 QT039999E R E R E R E R E R E R E R E R E R E R E R E R E R

COAL01 24 5 1COAL02 1 10 1 7 7 1 1 9 4 4COAL03 20 4 2 3COAL04 9 3 6 1 18COAL05 1 2 4 2 3COAL06 2 3 15COAL07 6 1 1COAL08 9 1 7 44 1COAL09 30 3 7COAL10 14 7 2 15COAL11 4 19 58 2COAL12 4 16 1COAL13 5 2COAL14 3 24 4COAL15 7 2 1 7COAL16 1COAL17 1COAL18 1 1 1 9 3 6 1 1COAL19 6 119 4 2 5COAL20 1 30 5 4COAL21 3 1COAL22 8 3 3COAL23 1 2COAL24 17 3 2COAL25 47 13 2 1 3 31COAL26 2 17 3COAL27 3 9 15 2 13 1COAL28COAL29 1 32COAL30 8 17COAL31COAL32 3 18 1


31

Trichoptera Trichoptera Trichoptera Trichoptera Trichoptera Trichoptera Trichoptera Trichoptera Trichoptera Trichoptera Trichoptera TrichopteraHydropsychidae Polycentropodidae Ecnomidae Tasimiidae Conoesucidae Helicopsychidae Calocidae Helicophidae Odontoceridae Atriplectididae Calamoceratidae Leptoceridae

Code QT069999 QT079999 QT089999 QT139999 QT159999 QT179999 QT189999 QT199999 QT229999 QT239999 QT249999 QT259999E R E R E R E R E R E R E R E R E R E R E R E R

COAL01COAL02 33 7 1 7 3 1 8 27 3COAL03 5 7 17COAL04 13 36 8 4 15 2 18 1COAL05 1 1 10COAL06 24 10 2 1 1 16 4 4COAL07 5 4 1 18 33 20 6COAL08 5 1COAL09 2 3 1 2 31 1 3COAL10 1 21COAL11 2 18 5COAL12 40 2COAL13 1COAL14 4COAL15 2COAL16 4COAL17 6 6COAL18 1 7COAL19 1COAL20 1COAL21COAL22 1COAL23 1 9 10COAL24 1 17 2COAL25 10 33 12COAL26 3 13COAL27 1 12COAL28 28COAL29 1 8COAL30 20COAL31 16COAL32 4


32

Appendix 2: Habitat Variables and Water Quality Measurements


33

Code Name Temperature(oC)

Conductivity(µS/cm)

Turbidity(NTU)

Dissolved O2(mg/L) pH

COAL01 Coal @ Richmond weir 21 556 7.03 4.9 7.14COAL02 Coal @ Daisy Banks 19.1 125.7 2.94 7.56 7.6COAL03 Coal River @ Fingerpost Rd 19.3 670 2.5 6.3 7.16COAL04 Coal @ Estate Rd 16.9 529 2.47 9 7.79COAL05 Coal @ Bartonvale 19.7 696 2.6 7 7.38COAL06 Coal @ Pitcairn Hill 17.8 609 2.21 8.7 7.55COAL07 Coal d/s Craigbourne dam 16.6 576 2.79 10.6 8.31COAL08 Coal @ Eldon Rd Bridge 20.3 333 5.54 8 7.27COAL09 Coal below gorge 16.6 346 3.03 9 7.39COAL10 Coal @ Wattle Hill Rd 17.3 294 8.14 8.6 7.37COAL11 Coal @ Tunnack Rd. 20.6 197 12.2 9.9 7.5COAL12 Coal @ New Country Marsh Rd. 16.1 85 5.62 10 7.3COAL13 Pages Ck @ Commercial Rd 21.3 633 29.1 10.9 7.48COAL14 Inverquharity Rivulet @ Prossers Rd 22.7 1030 5.21 18.2 8.64COAL15 Native Hut Rt @ Estate Rd 19.7 953 5.2 7.3 7.38COAL16 Native Hut Rt u/s Campania 16.5 1234 5.25 80 7.57COAL17 White Kangaroo Rt @ Stratford 18.4 71.9 1.7 8.2 7.54COAL18 White Kangaroo Rt @ Mosquito Plains 19.1 455 1.76 10.1 8.04COAL19 White Kangaroo Rt @ Ferniehurst Hill 16.8 58.6 0.86 10.3 8.31COAL20 White Kangaroo Rt @ Brown Mt Rd. 13.8 52 0.91 6.5 7.02COAL21 Broad Valley Ck. 19.3 299 0.86 8.6 7.86COAL22 Watts Gully Rt 18 109.7 0.76 3.7 7.53COAL23 Birmingham Ck nr Limekiln Hill. 17.5 2.24 34.1 9.2 8.27COAL24 Wallaby Rt d/s sewage ponds 20.4 1233 2.43 10.1 7.82COAL25 Wallaby Rt @ Rhyndaston Rd. 19.5 181.5 2.16 8.2 7.83COAL26 Craigbourne Ck @ Link Rd 19.8 161.2 1.71 7.9 6.33COAL27 Unnamed trib of Craigbourne Ck. 20.5 244 10.2 9.2 7.23COAL28 Unnamed trib off Craigbourne Ck. 14.7 74.8 3.35 3.5 6.1COAL29 Burns Ck near Eldon Bridge Rd. 24.7 782 1.82 7.4 6.97COAL30 Burns Ck @ Rabbit Hill Rd. 19.4 64.9 2.07 7.8 7.14COAL31 Hunters Swamp Ck @ Rhyndaston Rd. 15.6 140.8 77.8 6.8 7.41COAL32 Aarons Ck @ Stonor Rd. 14.7 842 3.99 8.7 6.91

Water quality parameters for sites sampled in Spring 2000


34

Code Name Northing Easting Distance fromSource (km)

Trailing BankVegetation

Bedslope Av StreamWidth (m)

COAL01 Coal @ Richmond weir 5268100 536075 66 0 0.004 12COAL02 Coal @ Daisy Banks 5269700 536100 64.5 1 0.004 4.6COAL03 Coal River @ Fingerpost Rd 5273500 535600 58.9 0 0.0025 6COAL04 Coal @ Estate Rd 5276000 537200 54.2 1 0.0048 4.33COAL05 Coal @ Bartonvale 5281950 535900 47 0 0.0027 4.67COAL06 Coal @ Pitcairn Hill 5286200 532800 40.9 0 0.004 12.67COAL07 Coal d/s Craigbourne dam 5288150 533150 36.9 0 0.04 4.33COAL08 Coal @ Eldon Rd Bridge 5292650 533950 31.9 1 0.005 7.33COAL09 Coal below gorge 5294000 532700 29.3 1 0.013 4.67COAL10 Coal @ Wattle Hill Rd 5302500 534300 17.4 0 0.005 3.83COAL11 Coal @ Tunnack Rd. 5300500 538300 9.1 0 0.005 3.33COAL12 Coal @ New Country Marsh Rd. 5295400 542800 2.1 0 0.006 2.1COAL13 Pages Ck @ Commercial Rd 5267600 535800 10.2 1 0.003 1COAL14 Inverquharity Rivulet @ Prossers Rd 5272850 537850 3.8 1 0.0067 2COAL15 Native Hut Rit @ Estate Rd 5276000 536200 14.9 0 0.0055 1.87COAL16 Native Hut Rit u/s Campania 5281800 530600 5.5 0 0.001 1.83COAL17 White Kangaroo Rit @ Stratford 5277900 538100 19 3 0.008 12COAL18 White Kangaroo Rt @ Mosquito Plains 5281100 539800 14.6 1 0.0067 4COAL19 White Kangaroo Rt @ Ferniehurst Hill 5282600 539300 12.6 3 0.013 3.67COAL20 White Kangaroo Rt @ Brown Mt Rd. 5284600 539200 10.5 1 0.008 2.83COAL21 Broad Valley Ck. 5277900 538500 4.9 1 0.027 1.5COAL22 Watts Gully Rt 5279100 538900 4.8 0 0.02 1.17COAL23 Birmingham Ck near Limekiln Hill. 5285600 533200 4.1 0 0.04 0.47COAL24 Wallaby Rt d/s sewage ponds 5288900 531100 10.7 0 0.01 3.83COAL25 Wallaby Rt @ Rhyndaston Rd. 5291200 529900 8.9 1 0.01 2.27COAL26 Craigbourne Ck @ Link Rd 5291100 535700 4.1 1 0.0125 0.3COAL27 Unnamed trib of Craigbourne Ck 5291100 535700 3.7 2 0.0125 1.27COAL28 Unnamed trib off Craigbourne Ck. 5291000 537100 2.2 1 0.026 1.77COAL29 Burns Ck near Eldon Br Rd. 5293200 534600 6.1 0 0.013 1.33COAL30 Burns Ck @ Rabbit Hill rd. 5294400 535400 4 1 0.026 3.43COAL31 Hunters Swamp Ck @ Rhyndaston Rd. 5298500 530900 1.8 1 0.027 0.13COAL32 Aarons Ck @ Stonor Rd. 5302400 535600 3.1 1 0.025 1.17

Predictor variables for the Spring Edgewater models


35

Code Name Northing Easting Boulder Score Mean Depth(cm) Bedslope AV Stream Width

(m)COAL02 Coal @ Daisy Banks 5269700 536100 1 10 0.004 4.6COAL04 Coal @ Estate Rd 5276000 537200 1 15 0.0048 4.33COAL06 Coal @ Pitcairn Hill 5286200 532800 1 10 0.004 12.67COAL07 Coal d/s Craigbourne dam 5288150 533150 1 10 0.04 4.33COAL08 Coal @ Eldon Rd Bridge 5292650 533950 4 15 0.005 7.33COAL09 Coal below gorge 5294000 532700 2 15 0.013 4.67COAL11 Coal @ Tunnack Rd. 5300500 538300 3 10 0.005 3.33COAL12 Coal @ New Country Marsh Rd. 5295400 542800 0 10 0.006 2.1COAL18 White Kangaroo Rt @ Mosquito Plains 5281100 539800 2 10 0.0067 4COAL19 White Kangaroo Rt @ Ferniehurst Hill 5282600 539300 1 10 0.013 3.67COAL20 White Kangaroo Rt @ Brown Mt Rd. 5284600 539200 0 7.5 0.008 2.83COAL24 Wallaby Rt d/s sewage ponds 5288900 531100 1 5 0.01 3.83COAL25 wallaby Rt @ Rhyndaston Rd. 5291200 529900 0 15 0.01 2.27COAL26 Craigbourne Ck @ Link Rd 5291100 535700 0 5 0.0125 0.3

Predictor Variables for the Spring Riffle model

Documents

Aquatic Ecology of Rivers in the Coal River Catchment · Aquatic Ecology of Rivers in the Coal River Catchment A Report Forming Part of the Requirements for State of Rivers Reporting