Environmental aspects of the Anthony–Pieman hydropower scheme

Pieman Sustainability Review June 2015 FACT SHEET

Background The Anthony–Pieman hydropower scheme provides a highly valued and reliable source of electricity. The total water storage is 512 gigalitres and the average annual generation is 2367 gigawatt hours. Construction of the Anthony– Pieman hydropower scheme has resulted in creation of water storages (lakes) and alterations to the natural flow of existing and streams. The Pieman Sustainability Review is a review of operational, social and environmental aspects of Anthony–Pieman hydropower scheme influenced by Hydro . This fact sheet elaborates on environmental and health information presented in the summary report of the Pieman Sustainability Review, available at http://www.hydro.com.au/pieman-sustainability-review

Ecology of the Anthony-Pieman peppermint (Eucalyptus coccifera) forest and woodland hydropower scheme and alpine heathlands. Threatened species Vegetation The West bioregion has a low diversity of flora and fauna The Anthony–Pieman hydropower scheme mostly falls compared to other bioregions in Tasmania. However, within the bioregion which includes the the natural habitats of the West bioregion are generally west and south-west of Tasmania but excludes the north- intact and it is the Tasmanian bioregion least impacted by west. The Tasmanian West bioregion is characterised by human activities. Therefore there are few threats to flora high rainfall and wet vegetation types, predominantly and fauna in the Anthony–Pieman hydropower scheme. rainforest, wet eucalypt forests, buttongrass moorland and wet scrub. The upper eastern parts of the Anthony– There are 23 threatened species (two mammals, four Pieman hydropower scheme fall within the Tasmanian birds, one reptile, one fish, nine invertebrates and six plant Central Highlands bioregion. species) recorded from the Anthony–Pieman hydropower scheme, particularly the middle and lower areas The rainforests of western Tasmania are dominated where water storages and associated by myrtle beech (Nothofagus cunninghamii). hydropower infrastructure are located. Fourteen Sassafras (Atherosperma moschatum) and celery top threatened plants and two threatened animal species (Phyllocladus aspleniifolius) are also common. At lower have been recorded in sub-alpine and alpine habitats in elevations in the Anthony–Pieman hydropower scheme the upper parts of the Anthony–Pieman hydropower stringybark (Eucalyptus obliqua) is the dominant wet scheme above the Hydro Tasmania hydro generation forest eucalypt, replaced by gum-topped stringybark infrastructure. These species are not particularly affected (Eucalyptus delegatensis) at higher elevations. Near the by hydropower operations. They generally occupy coast, non-forest vegetation communities dominate, restricted habitats that are sensitive to disturbance. particularly buttongrass moorland and western wet scrub communities. At higher elevations, including the Two threatened species that are directly affected by headwaters of the Henty and Pieman rivers, sub-alpine Hydro Tasmania operations are the azure kingfisher and alpine vegetation occur, including alpine yellow gum (Ceyx azureus subsp. diemenensis) and Australian (Eucalyptus subcrenulata) forest and woodland, snow grayling (Prototroctes maraena) which are both known to occur in the and the downstream of Reece Dam. The azure kingfisher is listed SHEET FACT as endangered in the Tasmanian Threatened Species Protection Act 1995 (TSP Act) and the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). It is a small (14 cm long) brilliant azure blue bird with an orange breast that nests in burrows dug into the bank of a river or creek. The azure kingfisher dives into streams to catch small fish. The Threatened Species Listing Statement1 for the azure kingfisher identifies a potential threat to the species from fluctuating water levels in controlled rivers that may flood nest tunnels excavated low in the banks of rivers. The Figure 1: Australian Grayling juveniles (80 mm approx.) captured during flooding of sections of rivers upstream of dams is also December 2013 capture/translocation period. Photo taken by Rob likely to have removed potential breeding and foraging Freeman (IFS) habitat for the species. The Australian grayling is listed as vulnerable in the TSP magnitude of flow releases can potentially affect Act and the EPBC Act. It is a diadromous fish species physical and ecological processes such as: (has life stages in both fresh and marine waters) that • influencing the composition of aquatic and riparian grows to 300 mm and has a distinctive cucumber communities smell. Adult fish live in freshwater where they lay their • alteration of river bed and channel morphology eggs in gravel on the bottom of rivers. On hatching, with prolonged low-velocity flows causing siltation the larvae are swept downstream into coastal waters and smothering of habitat, and prolonged high- where they remain as juveniles for about six months velocity flows causing scouring and erosion before returning to fresh water. The major threat to this • potential impacts on the reproductive success species is the construction of barriers that prevent adults of Australian grayling through changed flow migrating upstream and larvae moving downstream. regimes during the spawning season and physical Australian graylings have been recorded in the Pieman alteration to spawning habitat. River downstream of Reece Dam and in the Henty River downstream of the Anthony–Pieman hydropower • Dams are a barrier to fish passage and thus affect scheme. In December 2013, in a pilot study to assess the the sustainability of populations of migratory fish. feasibility of implementing a fish relocation program at There are populations of Australian grayling and the Reece Dam, 20 grayling were caught and translocated spotted galaxiid (Galaxias truttaceus) in the Pieman to locations upstream from Reece Dam (Figure 1). This River below Reece Dam and in the Henty River that was the first time Australian graylings had occurred in the cannot access upstream breeding habitats due to the Pieman River since the Reece Dam was constructed. presence of a dam. The impact of Hydro Tasmania operations on populations of other aquatic fauna and Hydro Tasmania carefully manages potential impacts flora species and their habitats is not well understood. on threatened species from maintenance and upgrade • Canals, pipelines and penstocks provide links between works. Any works require an Environmental Impact waterways that did not exist previously and thus Assessment as part of the project planning process. provide a mechanism for the transfer of aquatic Any potential impacts on threatened species are pests and pathogens, pest weeds, introduced fish, addressed by an Environmental Management Plan to and native fish to areas where they did not originally eliminate, or at least, minimise risks. occur. Although there are no incidences of the Environmental issues transfer of aquatic pests within the Anthony–Pieman hydropower scheme, the enhanced connections of There are few significant environmental issues within waterways through hydropower infrastructure can the Anthony–Pieman hydropower scheme because the facilitate the spread of pests and pathogens. For natural environment is largely intact. However there are example, there have been sub-catchment transfers of environmental issues associated with Hydro Tasmania redfin ( ) and Canadian pondweed water storages and management of rivers, including: Perca fluviatilis (Elodea canadensis) in the upper , via • Flow modification downstream of dams, particularly flow diversion infrastructure. The transfer of these in the Pieman and Henty Rivers. The timing and pests and native fish can pose a threat to endemic species. 1 Threatened Species Section (2012). Listing Statement for Ceyx azureus subsp. diemenensis (azure kingfisher). Department of Primary Industries, Parks, Water and Environment, Tasmania.

Pieman Sustainability Review Environmental aspects of the Anthony–Pieman hydropower scheme 2 Pests and weeds FACT SHEET FACT Phytophthora and Melaleuca (paper barks and honey-myrtles). To date myrtle rust has not been identified in areas Root-rot, or dieback fungus (Phytophthora cinnamomi) is an introduced water mould that can cause plant disease where Hydro Tasmania operates in the Anthony–Pieman hydropower scheme. and death in native Tasmanian vegetation. It poses a serious threat to susceptible plant species found in open Weeds vegetation in lowland environments (below 700 m) such There are widespread infestations of both pink pampas as moorlands, heathlands and dry eucalypt forests where grass (Cortaderia jubata) and toetoe pampas grass rainfall is greater than 600 mm. Phytophthora has the (Austroderia richardii) around Rosebery and along the potential to significantly impact the ecology of susceptible south of Tullah. Other invasive weeds native vegetation communities and threatened plant species. There are confirmed records of Phytophthora that are widespread in the Anthony–Pieman hydropower scattered throughout the Anthony–Pieman hydropower scheme are blackberry (Rubus fruticosus agg.), Canary scheme, with more frequent records from along the broom (Genista monspessulana), English broom (Cytisus Pieman River, near Savage River and around scoparius) and gorse (Ulex europaeus). and . There are also records in the south of the Anthony–Pieman hydropower scheme around Lake River health Plimsoll and and along the Henty River. The impact of constructing dams and power stations within rivers and the resultant changes to river health is Chytrid frog fungus well documented and includes changes in the biological Chytrid frog fungus (Batrachochytrium dendrobatidis) community (e.g. fish, invertebrates and vegetation) and is an introduced fungus that infects the skin of frogs, their associated habitats. Habitat change often occurs destroying its structure and function, resulting in death due to changes in the natural flow regime and sediment in most cases. The wet Tasmanian climate provides transport through the catchment. Hydro Tasmania ideal conditions for chytrid fungus to spread. Two undertook a comprehensive study in 1999 to quantify endemic frog species, the Tasmanian froglet (Crinia the impact of hydro-electric operations on riverine tasmaniensis) and the Tasmanian tree frog (Litoria habitat4, which included the construction of a number of burrowsae) occur in the Anthony–Pieman hydropower models that provide an assessment of river health using scheme and are potentially threatened by the chytrid macroinvertebrates. This study showed that the riverine fungus as their range overlaps with chytrid-affected habitat and invertebrate community immediately areas2. The Tasmanian tree frog is considered to be highly downstream of Hydro Tasmania dams and power stations susceptible to the disease. were significantly impacted close to dams but that areas A recent contraction in the range of the Tasmanian further downstream recovered rapidly. froglet in chytrid-affected areas has been linked to the River health monitoring presence of the disease. The common froglet (Crinia signifera), brown tree frog (Litoria ewingi) and eastern A preliminary assessment of river health immediately banjo frog (Limnodynastes dumerili subsp. insularis), downstream of Hydro Tasmania dams and power which all occur within the study area, are considered to stations was undertaken in 2013–14 as part of the be at low risk from the disease. The range of the smooth Pieman Sustainability Review. River health is assessed froglet (Geocrinia laevis), which also occurs in the using the standard AusRivAS method, whereby a river Anthony–Pieman hydropower scheme, overlaps with the site is compared with a reference benchmark within a chytrid-affected area but there has been no observed model using macroinvertebrates as the indicator of river range contraction in this species. health. Hydro Tasmania uses a number of models that Hydro Tasmania manages the risk of contamination and/ were developed specifically for catchments managed or spread of Phytophthora fungus and chytrid fungus for hydro-electricity generation, which are similar to by implementing the hygiene protocols (including the the AusRivAS models used nationally by government 5 wash down of waders, boots, equipment and vehicles) agencies and Rivercare groups . described in the manual ‘KEEPING IT CLEAN – A Tasmanian field hygiene manual to prevent the spread of freshwater pests and pathogens’3. Hydro Tasmania 2 Phillips, A., Voyles, J., Wilson, D. and Driessen, M.. (2010). Tasmanian Chytrid also has a policy of keeping vehicles clean and free of Management Plan. Biodiversity Conservation Branch, Department of mud to prevent the spread of weeds and diseases. Primary Industries, Parks, Water and Environment, Tasmania. 3 Allan, K. and Gartenstein, S. (2010). KEEPING IT CLEAN - A Tasmanian Myrtle rust field hygiene manual to prevent the spread of freshwater pests and pathogens. NRM South, Hobart. Available online at www.dpipwe.tas.gov.au/ An emerging pathogen threat in Tasmania is myrtle rust Documents/15130802_52keepingitcleanspreadswe.pdf (Puccinia psidii), a disease of plants in the Myrtaceae 4 Davies et al. 1999 family, including Eucalyptus, Leptospermum (tea tree), 5 Schofield and Davies 1996, Wright et al 1984, http://ausrivas.ewater.com.au/

Pieman Sustainability Review Environmental aspects of the Anthony–Pieman hydropower scheme 3 The river models produce an observed over expected in the macroinvertebrate community based on score (O/E score) by comparing the ratio of the observed important habitat characteristics irrespective of season. SHEET FACT family taxa (O) at a chosen test site with the expected Newton Creek was equivalent to the reference for family taxa (E) from groups of reference sites that community composition and community structure represent the reference condition at the time the models in spring and for combined seasons but significantly were developed. The models predict the likelihood of impaired for community composition and severely taxa occurring at a test site based on groups of reference impaired for community structure in autumn (Table 1). sites with similar habitat and landscape characteristics. The Hydro Tasmania RIVPACS regional model O/E Community composition and community structure in scores are then assigned a condition band to assist with the Henty River was significantly impaired in spring and interpreting the model outputs. The scores are divided likely to have been severely impaired in autumn due to into impairment bands for reporting purposes: zero flow; and remnant pools would have provided the only refuge for some taxa in autumn (Table 1). However, D — extremely impaired despite the impacts on community structure and C — severely impaired composition, the condition of the aquatic habitat at the three sample sites on the Henty River and its tributaries B — significantly impaired was found to be generally good to excellent (Figure 2). A — unimpaired or equivalent to reference Figure 2: Habitat condition scores for river health sites in the X — more diverse than reference. upper Henty River catchment in 2013–2014

Henty River health Seasonal average Spring 2013 Autumn 2014 The river health assessment immediately downstream 135 120 Excellent (103-135) of the three in-stream dams on the Henty River and its 105 tributaries gave varied results when assessed in 2013–14 90 Good (67-102) (Table 1). Macroinvertebrate community composition 75 in White Spur Creek was equivalent to the reference in 60 Fair (31-66) spring and the combined season results, but significantly 45 30 Riverine habitat conditon score score conditon habitat Riverine impaired in autumn. Community structure in White Spur 15 Poor (0-30)

Creek was significantly impaired in spring and autumn 0 but equivalent to the reference for the combined season Dam Dam Dam Dam Creek Creek Creek Newton Newton of Henty Whitespur Whitespur Creek and Henty Dam Henty River Henty of Newton

results. The combined season model is a better indicator White Spur White Spur downstream downstream Henty River River Henty downstream Newton Dam Newton downstream downstream downstream downstream of river health because it accounts for seasonal variation

Table 1: River health condition and scores for macronivetebrate community composition and structure for the Henty River and its tributaries

River site No. of Most Community composition Community structure years recent (O/E presence absence) (O/E rank abundance) with year data assessed Spring Autumn Combined Spring Autumn Combined season season

Whitespur Creek and A B A B B A 1 2013/14 Whitespur Dam (0.76) (0.83) (0.84) (0.74) (0.60) (0.79)

Henty River downstream of B Flow not Flow not B Flow not Flow not 1 2013/14 Henty Dam (0.59) present present (0.59) present present

Newton Creek downstream of A B A A (C) A 1 2013/14 Newton Dam (1.06) (0.55) (0.89) (0.93) 0.30 (0.81)

X X X X X A Henty River at Highway 11 2013/14 (1.25) (1.24) (1.27) (1.21) (1.20) (1.06)

Pieman Sustainability Review Environmental aspects of the Anthony–Pieman hydropower scheme 4 FACT SHEET FACT

Figure 3: Henty River looking upstream from the bridge (March 2014)

Pieman River health Recreational fishing River health monitoring in the Anthony–Pieman Recreational trout fishing is carried out in a number hydropower scheme has been limited. Where preliminary of dams and rivers on the West Coast including the studies have been done, sites were either unimpaired or Pieman and Henty Rivers and Lake Rosebery and Lake significantly impaired (Table 2). It is currently unknown Mackintosh. Further information on the West Coast how rapidly the health of the Pieman River recovers trout fishery can be found on the Inland Fisheries downstream from Reece Dam. It was not possible to Service website: http://www.ifs.tas.gov.au/ sample further downstream of Reece, White Spur and Newton dams due to limited access.

Table 2: River health condition and scores for macronivetebrate community composition and structure for the Pieman River and its tributaries

River site No. of Most Community composition Community structure years recent (O/E presence absence) (O/E rank abundance) with year data assessed Spring Autumn Combined Spring Autumn Combined season season

Red Hills Creek downstream of 3 2013/14 A A A A B A Anthony Highway (0.84) (0.96) (0.93) (0.81) (0.61) (0.92)

Peejays Creek upstream of 3 2013/14 A A A B A A Anthony Highway (0.76) (1.10) (0.93) (0.74) (0.98) (1.02)

Pieman River downstream of 1 2013/14 B B B B B Outside Stringers Creek (0.70) (0.59) (0.52) (0.58) (0.45) model experience

Pieman Sustainability Review Environmental aspects of the Anthony–Pieman hydropower scheme 5 1.6 1.6 SHEET FACT

1.4 1.4

1.2 1.2

1 1 0.8 0.8

Spring O/Erk 0.6

Spring O/Epa 0.6 0.4 0.4 0.2 0.2 0 0

X band - lower bound (1.199) A band - lower bound (0.777) X band - lower bound (1.161) A band - lower bound (0.726) B band - lower bound (0.356) C band - lower bound (0.0) B band - lower bound (0.290) C band - lower bound (0.0)

1.6 1.6

1.4 1.4

1.2 1.2

1 1

0.8 0.8

0.6 0.6 Autumn O/Erk Autumn O/Epa 0.4 0.4

0.2 0.2

0 0

X band - lower bound (1.174) A band - lower bound (0.836) X band - lower bound (1.201) A band - lower bound (0.811) B band - lower bound (0.499) C band - lower bound (0.161) B band - lower bound (0.420) C band - lower bound (0.029)

1.6 1.6 1.4 1.4 1.2 1.2 1 1 0.8 0.8 0.6 0.6 0.4 0.4 Combined seasons O/Erk Combined seasons O/Epa 0.2 0.2 0 0

X band - lower bound (1.213) A band - lower bound (0.794) X band - lower bound (1.113) A band - lower bound (0.776) B band - lower bound (0.375) C band - lower bound (0.0) B band - lower bound (0.439) C band - lower bound (0.102)

Figure 4: Community composition and structure O/E scores for each Hydro Tasmania river models for sections of the Henty River at Zeehan Highway from spring 1994 to 2014. Bands refer to the cut-off points of river condition bands.

Pieman Sustainability Review Environmental aspects of the Anthony–Pieman hydropower scheme 6