The Murray River's 'Sea to Hume Dam' fish passage program: Progress to date and lessons learned

© 2006 Ecological Society of Australia ECOLOGICAL MANAGEMENT & RESTORATION VOL 7 NO 3 DECEMBER 2006

173

F E A T U R E

doi: 10.1111/j1442-8903.2006.00307.x

Blackwell Publishing Asia

The Murray River’s ‘Sea to Hume Dam’ fish passage program: Progress to date and lessons learned

By Jim Barrett and Martin Mallen-Cooper

Since its commencement in

2001, a program to facilitate

fish passage on a major

stretch of Australia’s longest

river has installed eight

structures, testing and

modifying their design as

they go. What are the results

so far and what are the

implications for future

directions?

Jim Barrett

is Convenor of the Fish Passage Task

Force and Manager of the Native Fish Strategy,

Murray-Darling Basin Commission (GPO Box

409, Canberra, ACT 2601, Australia, Email:

[email protected]).

Martin Mallen-Cooper

is the Principal Consultant of Fishway Consulting

Services (8 Tudor Pl., St Ives, NSW 2075, Australia,

Email: [email protected]) and a

member of the Fish Passage Task Force.

Introduction

A

cross the Murray-Darling Basinthousands of weirs obstruct the

passage of fish and contribute to thesignificant declines in distributionand abundance suffered by many fishspecies. As part of an ambitious plan torehabilitate native fish populations,the Murray-Darling Basin Commission

(MDBC) is restoring fish passage alongthe Murray River from the sea upstreamto Hume Dam – a distance of 2225 km.The program, instigated in 2001, is amultistate process involving engineersand fish biologists in the design,construction, testing and evaluation offishways at 15 weirs and barragesalong the main stem of the river.The program incorporates adaptive

Figure 1. Golden Perch, a common migratory fish species in the Murray-Darling Basin whichrequires free passage upstream of adults and juveniles. The purpose of the Murray River Fishwaysis to enable free passage for the majority of native fish, including both large and small species.(Photo: I. Stuart)

emr_307.fm 73 Tuesday, October 31, 2006 1:41 PM

174

ECOLOGICAL MANAGEMENT & RESTORATION VOL 7 NO 3 DECEMBER 2006 © 2006 Ecological Society of Australia

F E A T U R E

management, investigating innovationand rapidly applying research results.This article provides information to dateon the successes of the program andlessons learned during the first five years.

Why the need for fishways?

All fish need to move along streams forfeeding, spawning, to seek shelter andrefuge, for dispersal of young fish, tocounter downstream displacement inhigh flows, and to recolonize afterdroughts. Almost every aspect of thelife history of fish involves movementand this can be over scales of metres orhundreds of kilometres (Lucas & Baras2001). These movements can be regularseasonal migrations undertaken bymuch of the population or they can beless regular and less well definedsuch as dispersal or recolonizationmovements which may be undertakenby large components of the fishcommunity or by a few individuals(Northcote 1998; Mallen-Cooper 2000).Movement is part of major ecologicalprocesses and preventing or inhibitingmovement has a range of impacts, fromincreased predation by birds belowbarriers to local extinctions of nativespecies. In the Native Fish Strategy forthe Murray-Darling Basin 2003–2013(MDBC 2004), barriers to fish passageare identified as one of eight key threatsto native fish populations. This is notunusual in regulated rivers throughoutthe world where lack of fish passage isfrequently identified as a major causeof the declines of freshwater fish(Northcote 1998).

The fish community of the lowerMurray River is listed as a threatenedecological community in New SouthWales. It contains a range of larger fishspecies such as Murray Cod (

Maccullo-chella peelii peelii

), Golden Perch(

Macquaria ambigua

) (Fig. 1), andthe threatened Silver Perch (

Bidyanusbidyanus

) and 11 small fish species(ranging from 20 to 70 mm in size) withfive of these known to specifically moveupstream (Table 1, Fig. 2). Of the smallfish, three are classified as threatened:Murray Hardyhead (

Craterocephalus

fluviatilis

), Olive Perchlet (

Ambassisagassizii

) and Flat-headed Galaxias(

Galaxias rostratus

).The objective of providing fish pas-

sage in the Murray River is to directlyameliorate these impacts and make amajor contribution to the rehabilita-tion of native fish by restoring streamcontinuity and migration pathways.

Early Australian fishways and their design evolution

Fishways have been present on theMurray River since the 1930s, usingdesigns imported from northern hemi-sphere prototypes (Box 1). Two earlyfishways were incorporated into thedesign and construction of Weir andLock No 6 (Murtho) in 1930 and No 15(Euston) in 1937 (Fig. 3). However,these ‘submerged–orifice’ designs, withrespective gradients of around 1-on-6and 1-on-9 (i.e. 1 m of vertical rise for9 m of horizontal length), were designedto the known standards of the daywhich applied to the powerful up-

stream swimming abilities of NorthernHemisphere salmon. Performing inan Australian context, however, thesefishways provided very limited passagefor native fish.

Later observations, includinglaboratory experiments in the 1980s(Mallen-Cooper 1994), gave a sounderunderstanding of swimming abilitiesand behaviour of native fish in fishways.With the Commission agreeing to funda fishway at Torrumbarry Weir, this newbiological information was applied toits design, and construction was under-taken in 1990. This was a ‘vertical–slot’design (Fig. 5) which had a gradient of1-on-18.

The operation of this structureproved to be a major advancement forfish passage in the Murray River. Accu-mulations of native fish downstream ofthe weir (an indicator of obstructedfish passage) declined dramaticallyfollowing its introduction, with over20 000 fish recorded as moving throughthe fishway in 3 years, including smallerfish (Mallen-Cooper 1999). At the same

Figure 2. Examples of small fish, Australian Smelt (upper pair) and Flyspecked Hardyhead(lower pair) collected in a new Murray River fishway at Lock 8. Small fish are often disadvantagedby traditional designs but the current fishways are specifically designed for the passage of thesespecies. (Photo M. Mallen-Cooper)

emr_307.fm Page 174 Tuesday, October 31, 2006 1:41 PM


175

F E A T U R E

time, native fish, particularly SilverPerch and Golden Perch, reappearedin significant numbers in the reaches ofthe Murray River upstream of Torrum-barry. Following Torrumbarry, othervertical-slot fishways were built else-where in Australia which increased theknowledge of the diversity and sizerange of fish that could use this type offishway design (e.g. Stuart & Mallen-Cooper 1999).

The total reconstruction of Torrum-barry Weir in 1994–1996 included thedecommissioning and replacement ofthe fishway. Further knowledge gained

during the period that the first fishwayoperated was applied to the new design.

The Sea to Hume Dam program

How i t s tarted

The vision of establishing fish passagealong the Murray River was firstarticulated in the mid-1980s when theMDBC (then River Murray Commission)established a working group of inter-state scientists to examine the issue offish passage. The working group

prioritized all the weirs on the mainstem of the Murray River, based ontheir ecological impact. As the firstpriority fishway, Torrumbarry fishwaywas constructed in the early 1990s.The next fishway was installed atYarrawonga Weir, the next barrierupstream, which coincided with theconstruction of a power station at thesite. Contemporary world practice foran 8-m-high weir suggested that thisshould be a fish lock. Although thiswas the first fish lock in the Murray-Darling Basin, the experience gainedat Torrumbarry on fish behaviour and

Table 1. List of fish species that occur, or are expected to occur, in the lower Murray River, lower lakes and tidal barrages (McDowall 1996; Harris& Gehrke 1997; Stuart et al. 2005)

Lower Murray River

Lower freshwater lakes and

tidal barrages

Estuarine species that enter freshwater

Migratory or known to

move upstream

Threatened species

Catfish • ?Silver Perch • � •Murray Cod • � •Crimson-spotted Rainbowfish • �Olive Perchlet • � •Flat-headed Galaxias • •Purple-spotted Gudgeon • •Golden Perch • • �Bony Herring • • �Australian Smelt • • �Flyspecked Hardyhead • • �Flathead Gudgeon • • �Murray Hardyhead • • •Southern Pygmy Perch • • •Yarra Pygmy Perch • • •Shortheaded Lamprey • • �Gudgeons (incl. Western Carp, • • �Midgeley’s and Lake’s Carp Gudgeon)Dwarf Flathead Gudgeon • • ?Common Galaxias • • �Congolli • • �Yellow-eyed Mullet • • �Small-mouthed Hardyhead • • �Black Bream • �Mulloway • �Estuary Perch • �Bridled Goby •Tamar River Goby •Soldierfish •Sandy Sprat •Swan River or Bluespot Goby •Lagoon Goby •Smooth Toadfish •

Non-native speciesCommon Carp • • �Gambusia • • �Redfin Perch • • �Goldfish • • �


176


F E A T U R E

swimming abilities provided directdesign input. These two fishwaysopened up 1115 km of river from Lock15 (Euston) to Hume Dam.

The genesis of the present program(involving a wholly funded fish passagestrategy from Hume Dam to the sea)was initially triggered by works requiredto comply with new OccupationalHealth and Safety (OH&S) standards atMurray River weirs. In 2000, RiverMurray Water (RMW) made a decision torefurbish Locks 1–11 and 15, coveringa continuous river length of 1110 km.This drew the issue of fish passage onthese structures to the attention ofMinisters under relevant State legisla-tion, with the result that, in March of2001, the Murray-Darling Basin Minis-terial Council adopted a Murray Riverstructural works program to providepassage for migratory fish from the seato Hume Dam, a distance of 2225 km.The program included the tidal bar-rages at the Murray mouth, which thenprovided the continuous length of riverconnected with the sea. This 8-yearprogram was estimated to cost a totalof $45 million.

Figure 3. Location of weirs and locks on the Murray River (Locks are numbered from 1 to 26;Y, Yarrawonga Weir; H, Hume dam; D, Dartmouth Dam). Ten fishways are completed (Barrages (3),Locks 7, 8, 9, 10, 15, 26 and Yarrawonga Weir) and a further 10 are planned over the next five yearsto complete the Sea to Hume Dam Program.

Box 1. International context

Fishways

are widespread throughout the developed world where there are barriers in rivers and where fish resources are

valued (Clay 1995). There are extensive fish passage projects in North America, notably the well-known Columbia/Snake river

system (Williams 1998) in the north-west and the Connecticut (Moffit

et al

. 1982) and other rivers in the north-east. Europe

has a long history of fishways and there has been a resurgence in this area in the last two decades (Cowx & Welcomme 1998;

FAO/DVWK 2002; Larinier

et al

. 2002) with examples on large rivers like the Rhine (Gebler 1998), Danube (Mader

et al

. 1998)

and Garonne/Dordogne rivers (Travade

et al

. 1998). Fishways are also widespread in South America (Quirós 1989) and the former

USSR (Pavlov 1989). There are, however, some major differences between these projects and the fishways on the Murray River.

The ‘Sea and Hume Dam’ program is one of the longest fish passage restoration projects, in terms of river length, in the world.

This is achievable in part because of the low gradient of the river, which means that all the weirs from the Barrages to Lock 15

inclusive are less than 5-m high, with most less than 3.5 m. The overseas examples mentioned above generally have steeper

gradients, some having much higher fishways passing dams of 5–20-m high; making the achievement of fish passage more difficult.

The other major difference between Australian fishways and those in many other countries is the comprehensive ecological

objectives of the Murray River program. With the exception of Germany and Austria where recent fish passage projects often

have holistic goals (Waidbacher & Haidvogl 1998; FAO/DVWK 2002), fishways in the northern hemisphere (Clay 1995) and

South America (Quiros 1989) tend to be targeted to large-bodied species, with the movement of other species considered

incidental. In contrast, the Murray River program aims to optimize the passage of the whole fish community and has a very

wide target size range (40–1000 mm) compared with fish passage projects in other countries.



177

F E A T U R E

At its inception the MDBC formedthe Fish Passage Task Force (FPTF) toprovide specialist technical advice onthe fishways and to provide continuityfor a lengthy program. The FPTF com-prises fish scientists and engineers fromacross the jurisdictions in the basin,along with the owner and operatorof the structures. The group’s primaryrole is to guide fishway design andevaluate the success of fish passage inthe Sea to Hume Dam program, with along-term, broader role of developing abasin-wide fish passage program.

Sett ing design cr i ter ia for the f ishways

The first challenge of the FPTF was toset ecological objectives for fish passagefor a whole-of-ecosystem approach to ariver reach with high conservation value;from these followed design criteria forthe fishways. Biology and engineeringare inherently linked in developingfishway design. The biological challengeis to build a model of fish migration,identifying species and life stage,seasonality of movement, response toflow, and interaction with river hydrology.

From that model, engineering andbiology need to interact as the cost-sensitive areas of the design are identifiedand design decisions can be made onan ecological basis.

Studies to date have shown that themigratory response of native fish spe-cies is related to season and river flow(O’Connor

et al

. 2005), which createsmigratory pulses (McDowall 1996;Mallen-Cooper 1999). Most fish movein spring and summer, tapering off inearly autumn. Within these seasons,Golden Perch and Silver Perch arestimulated to move by increases in riverflow. Immature and mature life stagesof these species also respond differentlyto varying increases in river flow. Smallfish species, such as Australian smelt,are moving mainly at the stable lowerflows while larger species such as BonyHerring and the non-native CommonCarp (

Cyprinus carpio

) are movingupstream in relation to increased tem-peratures which can occur over a widerange of flows (Mallen-Cooper 1999).

Significant ecological informationgaps still remain, however, requiringprecautionary design decisions to be

included. For example, little is knownabout the contribution that migratoryadult Murray Cod make to recoloniza-tion and recruitment of the populationas a whole, compared with adult fishthat may not be migratory. The FPTFconcluded that the fishways shouldenable movement of a wide size rangeof adult Murray Cod. The challenge forfishway design is therefore to incorpo-rate present data, identify knowledgegaps and include some flexibility in thefishway design.

Size classes

For fishway design, the migratory fishcan be grouped into three major sizeclasses: 20–70 mm (e.g. AustralianSmelt, Flyspecked Hardyhead, Gudgeonspecies); 90–600 mm (immature andmature Silver Perch and Golden Perch,Bony Herring, immature Murray Cod);and 600–1400 mm (adult Murray Cod).Providing passage for the full size rangeof fish would have increased cost to aprohibitive extent. Designing for thesmallest fish would need very low watervelocities and a long fishway whiledesigning for the largest fish wouldnecessitate very large fishway pools;such parameters have a major influenceon cost. The FPTF therefore identifieda goal of designing fishways to allowpassage at weirs for a substantial propor-tion of all species and life stages of fish.

A minimum size criterion of 40–60 mm was established for the fishwaydesigns, which is intended to enableupstream passage of approximately halfof the fish between 20 and 70 mm, withthe ecological objective of enablingdispersal of these species. Passing allfish between 90 and 600 mm (whichincludes species with well-knownmigratory patterns) was identified as agoal. A maximum size criterion of1000 mm was intended to enable theupstream passage of the majority of theadult Murray Cod.

Flow ranges

The range of river flows over which afishway operates has a major bearing

Figure 4. Fish are guided to the fishway entrance by manipulating flows over the weir andcreating a line of turbulence (indicated by a dashed arrow) leading to the fishway.


178


F E A T U R E

on its cost. The FPTF considered thatthe fishways needed to operate over awide range of flows. As differentspecies and life stages of fish migrate atdifferent flows, reducing the operationalrange could have greatly impactedsome life stages of some species.

These biological and hydrologicalcriteria determine specific aspects ofthe fishway design, and are adjustedaccording to the dimensions and con-figurations of the individual locks andweirs, which are also specifically man-aged to attract fish to the fishway byadjusting flow patterns (Fig. 4). For theMurray River, the vertical-slot design(Fig. 5) was used on a 1-on-32 gradientwith 3-m long by 2-m wide pools. Thestep height (head loss) between poolsis 0.1 m, which creates a maximumwater velocity of 1.4 m s

−

1

; com-bined with the pool volume this gen-erates a low turbulence of 40 W/m

3

.The pool size enables the passage ofMurray cod and the low water velocitiesand turbulence are intended for thesmall fish. The fishways also have rocksglued to the floor to enhance the pas-sage of crustaceans (Fig. 6).

Carp management in fishways

Concentrations of carp at fishwaysprovide opportunities for their removaland facilities need to be included inthe design phase. To date removal hasbeen through labour intensive trappingthat places considerable stress on nativefish. The ‘Williams’ carp separation cage’makes use of the differing behavioursof carp and native fish (Stuart

et al

. inpress) resulting in effective separationof carp. The cage is low-cost, is beingdesigned to be included in the new andexisting fishways and is likely tohave application throughout fishwaysin the southern Murray-Darling Basin.

Where are they being bui l t?

The Sea to Hume Dam program hasbeen underway since July 2001. It aimsto deliver 15 effective fishways at 13sites from the tidal barrages near theMurray Mouth to Weir and Lock 15 atEuston. Eight of the planned fishwayshave been installed; five at the riverine

Figure 5. Schematic diagram (a) and photo (b) of a completed vertical-slot fishway. Thisparticular design differs from earlier fishway designs in that it is specifically designed for theswimming ability and behaviour of small and large native fish. The design also functions at a widerange of river levels. (Photo: I. Stuart)



179

F E A T U R E

locks (Table 2) and three at the Barrages(Table 3).

At each site, the FPTF considersseveral options for the location, designand number of fishways. At the riverinelocks, fish passage along both banks waspreferred, but as this increased costssignificantly it was considered that, by

manipulating flows across the weir, asingle fish passage was adequate. At thetidal barrages, assessment showed thatall five weirs impede the passage of fish,but that low-cost, effective fishways arefeasible because the difference in waterlevels either side is very small. The twobarrage sites where fishways have been

completed were identified as the highestpriorities for intervention because ofthe high biomass of fish present.

A schedule is proposed that will seethe construction of fishways at all eightremaining structures by 2010. Theprogram will eventually be extendedto other major obstructions to fishmovement throughout the MurrayRiver system, and includes the decom-missioning of redundant structures.

Costs

The vertical-slot fishways presently beinginstalled at the Locks on the MurrayRiver are world-class in functionality.However, their broad-scale applicationthroughout the Basin is likely to becostly and therefore unlikely to bepractical. Even with the additional costof retrofitting the fishway to an existingRiver Murray Lock and Weir, the cost(about AUD$3m) represents only about7% of total estimated replacement costof the structure. In 2004, the FPTFconducted a workshop, facilitated bythe Australian Centre for Value Manage-ment, to explore opportunities to reducecosts of fishway design and constructionwhile ensuring that functionality andother benefits were preserved. Severalcost-saving fishway configurations wereidentified, and a recommendation madethat a research and development pro-gram be developed to explore additionaloptions.

A major factor in the cost is theslope of the fishway channel, whichdetermines the total length of the fish-way. Hence, an experiment was con-ducted at the Lock 8 fishway in 2005 tocompare the performance of variationsin the vertical-slot baffle at higher slopes.One finding was that separating thefunction of passing small fish and largefish is likely to reduce cost and improveperformance; that is, two fishways could

Table 3. Progress towards construction of fishways at the barrages

Year of completion Barrage Type of fishway Progress

2004 Tauwitchere Vertical-slot and rock ramp fishways Completed2005 Goolwa Vertical-slot fishway Completed≥ 2007 Three remaining barrages Up to 13 fishways may be needed, dependent

on results from Goolwa and Tauwitchere

Table 2.

Progress towards construction of fishways at Locks and Weirs

Year of completion Lock & Weir No. Progress

2004 8 Completed2004 7 Completed2005 9 Completed2005 15 Completed (Denil fishway)2006 10 Completed2007 1 Designed, ready for tender2008 3, 5, 112009 2, 42010 6

Figure 6. Rocks are glued to the floor of the vertical-slot fishway to enhance passage of crustaceans.The small shrimp Paratya (Mallen-Cooper 1999) and sometimes the larger freshwater prawns(Macrobrachium) are important migratory fauna in the lower Murray River. (Photo: M. Mallen-Cooper)


180


F E A T U R E

be cheaper than one. This significantnew knowledge is being applied to thedesign of an inexpensive fishway forsmall native fish. Small Denil fishwayshave been used for small fish in Japanand these are now being tested for

small native fish in the Murray River. Anexperimental Denil fishway for largernative fish was installed at Lock 15 inthe existing 1-on-9 fishway channel toimprove fish passage until the programreaches the site in 2008 (Fig. 7).

Performance of the new fishways

The tri-State research team (see monitor-ing, Box 2) has completed its assess-ment of the functionality of the Lock8 fishway, the first of the main-stemfishways, and collected 12 fish speciesand 27 215 individuals in 40 days ofsampling. Fish successfully reachingthe exit ranged in size from 40 mmlong gudgeons to 1030 mm MurrayCod and predation from birds hasdramatically reduced. The functionalityof the fishway meets the initial designspecifications but the biomass of verysmall fish (20–40 mm long – a sizethat was outside the original targetrange) was greater than expected. Thetri-State team has now successfullycompleted a range of innovativefishway experiments aimed atfacilitating passage of these fish andimproving passage of invertebrates.One of these experiments is usingthe existing vertical-slot fishway as afish lock, which has shown that thepassage of small fish such as FlyspeckedHardyhead, Gudgeons, Australian Smeltand Murray Rainbowfish, as well asfreshwater prawns, can be greatlyimproved.

Beyond the program

Downstream movement

The majority of actions addressing fishpassage problems have focused onprovision of upstream migration of fish,but there are major issues associatedwith the impediments to downstreammigration of fish. An FPTF workshopin 2003 (Lintermans & Philips 2003)engaged stakeholders in a review,update and prioritization of the actionsnecessary to restore downstream fishmigration, and the need to develop anaction plan that will guide investmentin this area over the next three to fiveyears. Major issues associated withdownstream migration include:

• Inability of adults to return to home-sites after upstream spawning migra

-

tions or other movement

Figure 7. a and b. Denil fishway at Lock 15. Denil fishways are systematically roughened channelswith closely spaced U-shaped baffles connected by resting pools. The baffles creates zones of lowwater velocities near the base of the fishway channel that enable fish to ascend. This fishway ispresently being assessed. It has the construction advantage of being prefabricated off-site andhas potential at other selected sites in the Murray–Darling Basin. (Photo: M. Mallen-Cooper)



181

F E A T U R E

• Depletion of downstream fish popu

-

lations as barriers restrict colonizationfrom upstream areas

• Injuries to fish after passing throughor over weirs and spillways

• Larval fish settling out in unsuitableweir-pool habitats

• Fish being diverted into irrigationchannels and inappropriate habitats

• Fish being diverted into off-streamstorages, turbines, pumping inlets,etc.

Identification of these issues has ledthe MDBC to fund a project investigat-

ing downstream fish movements intoirrigation offtakes and pumps.

Extending the program beyond the Murray River

It is anticipated that the program of fishpassage will be extended to othermajor barriers throughout the Murray

Box 2. Monitoring

The

FPTF identified desirable performance outcomes for the fishways program. In brief these were:

• To pass a large biomass of fish comprised of all native fish species and all fish sizes, by voluntary fish movement primarily

aimed at upstream fish passage, but with downstream passage accommodated where feasible

• To provide fish passage for close to 100% of the time during the fish migrating months of August to April and to continue

operating during environmental weir pool raisings and lowerings

• To provide fishways of long life (design life = 100 years), and

• To accommodate appropriate monitoring and carp separation where practical

To monitor and assess the outcomes of the project the MDBC, in 2001, established a team of freshwater scientists from

the states of New South Wales, Victoria and South Australia. This tri-state research team is conducting a comprehensive

research program that is sampling fish populations in the river (before and after installation of the new fishways) and

monitoring fish as they approach, pass through, and leave the fishways (Stuart

et al

.

2004). Four techniques are providing

data on the effectiveness of the newly installed fishways: (i) electrofishing below Locks 1–3; (ii) Passive Integrated

Transponder (PIT) tags at fishways; (iii) direct sampling of the fishways; and (iv) pre- and postconstruction comparison at the

barrages. The results are informing the design and placement of future fishways, and guiding improvements to newly installed

fishways.

PIT tags are small glass encapsulated tags with an individual code that are inserted into fish and can be decoded when

the fish passes a reader. This type of electronic monitoring enables the identification of (i) large-scale migrations of fish; and

(ii) passage time through fishways once the fish have successfully located the entrance.

Since its inception, the tri-state team has implanted 15 000 fish, including Common Carp, Golden Perch, Bony Herring,

Goldfish, Murray Cod, Silver Perch and Redfin Perch. An additional 5000 tagged fish are also at liberty from other research

programs within the Murray-Darling Basin. PIT readers are now operating at Locks 7, 8, 9, 10, 15 (Euston), 26 (Torrumbarry)

and Yarrawonga. At all newly completed fishways antennas have been installed at the entrance, exit and two midpoints to

provide detailed information regarding the behaviour of large-bodied fish within the fishways. This information is continuously

logged and the data is automatically relayed to the researchers weekly.

In 2003–2004 the MDBC funded the CSIRO to test a split-beam hydroacoustic system for counting fish. The results

demonstrated that it is possible to estimate total abundance and size structure of fish in large rivers and at a large scale;

count fish passing through fishways in both directions; estimate fish size and determine fish density, speed of movement

and coordinates in space even in moderately turbulent creeks as shallow as 1 m.

Trials are underway to test new technologies for remote sampling of fish including an underwater Dual-frequency

IDentification SONar (DIDSON) system for remotely studying the migration patterns of native fish. The DIDSON system uses

acoustic lenses to produce high-resolution video and is particularly useful in dark and turbid conditions where conventional

optical systems are ineffective. Trials of the DIDSON at Yarrawonga Weir, Lock 8 and the Murray mouth barrages revealed

detailed aspects of fish behaviour at close range that have immediate implications for fishway design and for interpreting the

results of monitoring. Further trials of the unit are currently being planned.


182


F E A T U R E

River system; that is, structures asso-ciated with auxiliary river channels(e.g. Mullaroo Creek and the Chowillasystem, Lake Victoria and the MenindeeLakes). It will also consider works toStevens Weir on the Edward River. TheMDBC is also addressing the issue of

redundant structures, including a reviewof criteria for assessing structures fordecommissioning. Other than theMurray River system, there are nearly4000 registered weirs throughout therest of the Murray-Darling Basin. Thevast majority of these are low-level weirs

(<3 m), requiring relatively simplefishways or fish passage solutions.The FPTF has developed criteria toprioritize fishway placement at thesebarriers across the basin, based onrankings of the characteristics of thefish species present, including theirthreatened status, the quality of fishhabitat present and economic con-siderations. The Task Force identifiedthe 20 priority sites in New South Wales,South Australia and Victoria most inneed of new fishways or modificationsto existing structures (Table 4).

Conclusions

A strength of the ‘Sea to Hume Dam’fish passage program has been theestablishment of the FPTF and thetri-State assessment team. Biologists,engineers and river operators workingtogether have ensured the fishwayshave been designed with transparentecological goals; and the existence ofthe FPTF enables the continuity ofexperience and expertise throughout

Table 4.

Barriers needing new fishways or modifications to existing fishways, listed in order ofpriority

Barrier name River State

Steven’s Weir Edwards River NSWMenindee Lakes Main Weir Darling River NSWCaseys Weir Broken River Vic.Boomi Weir Macintyre River QldCunnamulla Weir Warrego River QldGogelderie Weir Murrumbidgee River NSWRedbank Weir Murrumbidgee River NSWKerang Weir Loddon River Vic.Brewarrina Weir Barwon River NSWGowangardie Weir Broken River Vic.Gulf Regulator Creek–Barmah Lakes Vic.Loudoun Weir Condamine River QldMullaroo control structure Lindsay River–Mullaroo Ck Vic.Tea Garden Creek Weir Ovens River Vic.Bourke Weir Darling River NSWWalgett Weir Barwon River NSWNeil Turner Weir Maranoa River QldEulo Weir Paroo River Qld

Box 3. Communication to the public

To

raise community awareness of fish passage issues in the basin, and to increase understanding of the purpose and science

behind fishways, the FPTF has made extensive use of the media and has been involved in the development of educational

material. Examples include the brochures

: ‘What is a fishway?’

, an explanation of the principles behind fishways and

justification for their use; the recent

‘The River Murray Barrages and Fishways’

, which describes the ecology of fish species in

the Lower Lakes and Coorong, as well as the construction of fishways at the Tauwitchere and Goolwa barrages; and

‘Fish n’ Chips’

,

a description of the application of PIT tagging technology to assess fish movements and fishway effectiveness in the basin.

The FPTF is also developing a brochure to inform the public on activities associated with the upgrading of locks and weirs.

Interpretive signs have also been developed for fishways, both completed and under construction, at Goolwa and Lock 9.

These signs contain information about the design and purpose of the fishway, an explanation of the ‘Sea to Hume Dam’ fish

passage program, and list the species expected to pass through the fishway.

A video/DVD has also been produced which gives an overview of the basin and its native fish, describes the need for fish

passage and fishways, and gives the viewer a ‘fish’s eye’ view of an animated vertical-slot fishway. This has proved extremely

popular at the numerous events that have been attended by the Native Fish Strategy team. A similar project is underway to

animate the rock-ramp fishway at Tauwitchere barrage, to complement the audio-visual material available.

The MDBC is committed to the continued production of high quality publications that inform and educate all stakeholders

and the wider community on fish passage in the basin. Planned activities include the production of a regular newsletter

updating progress with the Sea to Hume Dam fish passage program and a brochure on methods of tracking fish movements,

as well as further development of the NFS website to include regularly updated results of the fishways monitoring program.

Publications can be obtained from www.mdbc.gov.au.



183

F E A T U R E

this long-term program. The interactionof scientists from three states in theassessment program has been a key toachieving a high level of research andthe performance of the fishways hasprovided further confidence for stateagencies to install fishways.

The construction of fishways is butone element of the Native Fish Strategyof the MDBC (MDBC 2004) – withother elements including protectingand rehabilitating fish habitat andthreatened species, controlling alienfish species, protecting threatenednative fish species, managing fish trans-location and stocking and communi-cating the program to the public(Box 3). Providing fish passage on theMurray River is a very tangible andsignificant step towards the strategy’sgoal of restoring native fish populations.

Acknowledgements

Thanks is extended to the members ofthe Fish Passage Task Force: JohnPrentice (RMW), Cameron Lay, LeeBaumgartner (NSW DPI (Fisheries)),Tim O’Brien and Ivor Stuart (VIC DSE(ARI)), Brenton Zampatti (SARDI),Andrew Berghuis (Queensland DPI &Fisheries), Brian Cooper (NSWDepartment of Commerce), BrentonErdmann (SA DWLBC), Darryl Jones (SAWater) and Angelo Rossi and RobertAlaia (SA Water Project Managers).David Dreverman (General ManagerRiver Murray Water) made usefulcomments on the draft text.

References

Clay C. H. (1995)

Design of Fishways and OtherFish Facilities

, 2nd edn. Lewis, Boca Raton,Florida.

Cowx I. G. and Welcomme R. L. (1998)

Rehabilita-tion of Rivers for fish.

FAO. Blackwell Sciences,Oxford.

FAO/DVWK (2002)

Fish Passes – Design, Dimen-sions and Monitoring

. FAO, Rome.Gebler R. (1998) Examples of near-natural fish

passes in Germany: Drop structures conversions,fish ramps and bypass channels. In:

Fish Migra-tion and Fish Bypasses

(eds M. Jungwirth,S. Schmutz and S. Weiss), pp. 403–420.Fishing News Books, Oxford.

Harris J. H. and Gehrke P. C. (1997)

Fish andRivers in Stress: the NSW Rivers Survey

.NSW Fisheries Office of Conservation and theCooperative Research Centre for FreshwaterEcology, Cronulla.

Larinier M., Travade F. and Pocher J. P. (2002) Fish-ways: Biological basis, design criteria andmonitoring.

Bulletin Français de la Pêche et dela Pisciculture

,

364

suppl.

, 208 p.Lintermans M. and Phillips B. (2003)

DownstreamMovement of Fish in the Murray-Darling Basin

.Murray-Darling Basin Commission, Canberra.

Lucas M. and Baras E. (2001)

Migration of Fresh-water Fishes

. Blackwell sciences, Oxford.Mader H., Unfer G. and Schmutz S. (1998) The

effectiveness of nature-like bypass channels ina lowland river, the Marchfeldkanal. In:

FishMigration and Fish Bypasses

(eds M. Jung-wirth, S. Schmutz and S. Weiss), pp. 384–402.Fishing News Books, Oxford.

Mallen-Cooper M. (1994) Swimming ability of adultgolden perch,

Macquaria ambigua

(Percicthyidae),and adult silver perch,

Bidyanus bidyanus

(Teraponidae), in an experimental vertical-slotfishway.

Australian Journal of Marine andFreshwater Research

45

, 191–198.Mallen-Cooper M. (1999) Developing fishways for

non-salmonid fishes: A case study from theMurray River in Australia. In:

Innovations in FishPassage Technology

(ed. M. Odeh), pp. 173–195. American Fisheries Society, Bethesda,Maryland.

Mallen-Cooper M. (2000) Taking the mystery out ofmigration. In:

Fish Movement and Migration

(eds D. A. Hancock, D. C. Smith and J. D.Koehn), pp. 101–111. Australian Society forFish Biology Workshop Proceedings, Bendigo,Victoria.

McDowall R. M. (ed.) (1996)

Freshwater Fishes ofSouth-eastern Australia

. Reed, Sydney.Moffit C., Kynard B. and Rideout S. (1982) Fish

passage facilities and anadromous fish restora-tion in the Connecticut River Basin.

Fisheries

7

, 2–11.Murray-Darling Basin Commission (2004)

NativeFish Strategy for the Murray-Darling Basin2003–13

. Murray-Darling Basin Commission,Canberra.

Northcote T. G. (1998) Migratory behaviour of fishand its significance to movement through riverinefish passage structures. In:

Fish Migration andFish Passes

(eds M. Jungwirth, S. Schmutz andS. Weiss), pp. 3–18. Fishing News Books,Oxford.

O’Connor J. P., O’Mahony D. J. and O’Mahony J. M.(2005) Movements of

Macquaria ambigua

, inthe Murray River, south-eastern Australia.

Journalof Fish Biology

66

, 392–403.Pavlov D. S. (1989)

Structures assisting themigrations of non-salmonid fish: USSR.

FAOFisheries Technical Paper, no. 308, Rome.

Quirós R. (1989)

Structures assisting the migra-tions of non-salmonid fish: Latin America

.COPESCAL Technical Paper, no. 5. Rome.

Stuart I., Baumgartner L., Zampatti B. and Barrett J.(2004) Fishways in Australia – an adaptiveapproach to improving fish passage along alarge river system. In: (eds D. G. Garcia DeJalon and P. V. Martinez), pp. 979–983. Pro-ceedings of the Fifth International Symposiumon Ecohydraulics, 12–17 September 2004,IAHR, Madrid, Spain.

Stuart I., Ye Q., Higham J. and O’Brien T. (2005)

Fish Migration at Tauwitchere Barrage: NewOptions for Fish Passage. Report to theMurray-Darling Basin Commission.

ArthurRylah Institute for Environmental Research,Victoria.

Stuart I. G. and Mallen-Cooper M. (1999) Anassessment of the effectiveness of a vertical-slotfishway for non-salmonid fish at a tidal barrieron a large tropical/sub-tropical river. RegulatedRivers 15, 575–590.

Stuart I. G., Williams A., McKenzie J. and Holt T.(in press) Managing a migratory pest species:A selective trap for common carp. NorthAmerican Journal of Fisheries Management26 (4).

Travade F., Larinier M., Boyer-Bernard S. and Dar-tiguelongue J. (1998) Performance of four fishpass installations recently built on two rivers insouth-west France. In: Fish Migration and FishBypasses (eds M. Jungwirth, S. Schmutz andS. Weiss.), pp. 146–170. Fishing News Books,Oxford.

Waidbacher H. G. and Haidvogl G. (1998) Fishmigration and fish passage facilities in theDanube: Past and Present. In: Fish Migration andFish Bypasses (eds M. Jungwirth, S. Schmutzand S. Weiss), pp. 85–98. Fishing NewsBooks, Oxford.

Williams J. G. (1998) Fish passage in the ColumbiaRiver, USA and its tributaries: Problems andsolutions. In: Fish Migration and Fish Bypasses(eds M. Jungwirth, S. Schmutz and S. Weiss),pp. 180–191. Fishing News Books, Oxford.


The Murray River's 'Sea to Hume Dam' fish passage program: Progress to date and lessons learned

Documents

Transcript of The Murray River's 'Sea to Hume Dam' fish passage program: Progress to date and lessons learned