Introduction
This chapter deals with issues associated with the impacts of land and water users on the river and its associated values. The strategies developed suggest the need for a River Management Strategy for the Ord River to ensure that guidelines for improved management continue to be developed and adhered to.
Many of the issues associated with wise management of the river depend on information that has yet to be gathered. The unique nature of each river system means it is difficult to transfer information from one location to another. The general lack of information about tropical river systems makes it near impossible to proceed with wise management without significant research effort.
The management of the river cannot wait for the complete gathering and interpreting of research information but must proceed on the basis of the best existing knowledge while new knowledge is gained.
There are a number of agencies that have statutory responsibilities for managing waterways around Kununurra. These include the Water and Rivers Commission, the Water Corporation and the Shire of Wyndham East Kimberley. Local residents, tourists and tour operators also have a responsibility for minimising the impacts they have while enjoying the river.
Please note - It is important to recognise that the strategies developed in this chapter will need to be built on as new knowledge is developed and targets are achieved. At this stage they provide a starting point and a framework for commitment from all the parties involved in Land and Water Management on the Ord.
Goals
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To maintain and protect existing fish stocks with a view to increasing them if required in the future.
Fishing in the Ord River is a popular pastime for local residents and it acts as a draw card to visiting anglers (West et al,1996). There are a number of charter fishing operators, and commercial fishermen who rely on a healthy fishery to support their businesses.
The main target species for fishing on the Ord River are barramundi and bream (Sooty Grunter) (West et al, 1996).
There are bag limits in place for both of these fish with the barramundi bag limit being one fish per angler (size range 55cm –80cm), and bream 20 fish per angler with a minimum size of 25cm (Fishing for the Future, 1998). There are other species of fish found in the area including silver cobbler (catfish) that are fished, although these are not popular as a recreational fishing species.
Since the building of the Diversion Dam and Lake Argyle the habitat range of barramundi on the Ord River has been restricted to the area of the river below the Diversion Dam (Doupe and Bird, 1999). Bream and silver cobbler can be found in Lake Kununurra and Lake Argyle as well as the Ord River.
Current StatusThe absence of adequate fish stock information prevents any firm conclusions regarding fish stocks in the Ord River. The current barramundi stocks, however, do not appear to be in decline. The catch rate trends for the commercial fishery, general satisfaction levels for the recreational fishery and consistent anecdotal information (West et al, 1996) support this claim.
Fisheries WA are the lead agency involved in fish stock management and aquaculture development around the state. The principal local group involved in recreation fishing is the East Kimberley Recreational Fishing Advisory Committee (EKRFAC). The role of this committee is to provide advice and information to the Minister for Primary Industries and Fisheries. The EKRFAC is one of 12 regional RFAC committees located throughout the state.
There are three commercial fishermen fishing areas of the Lower Ord (downstream of Carlton Crossing) (R. Tregonning, pers comm). They are based in Wyndham and usually visit the Ord River two or three times a year as one of a number of rivers they fish in the area. They are not allowed to fish during the months of December and January. Their catch is relatively small, however, as they use nets to fish they do have some fish waste through bycatch (catching of non target species). They do not have the same size and bag restrictions as recreational fishers.
There are several fishing charters operating in the Lower Ord River area. Barramundi is the focus fish for these operations and they all abide by the barramundi regulations regarding size and number of fish taken.
There has been some barramundi tagging carried out in the Ord River.
Introduced SpeciesThere are no introduced species of fish present in the “wild”, however there is currently one introduced species being farmed in the ORIA – Redclaw Crayfish (Cherax quadricarinatus). There are strict regulations on the management of this species including pond construction (netting, fencing, etc, to prevent the escape of redclaw), and disease and quarantine protocols. For details see Fisheries Management Paper No.100 – The Aquaculture of Non-endemic Species in Western Australia (Thorne, 1997).
Current Projects Range ExpansionThe EKRFAC are interested in expanding the range of barramundi into Lake Kununurra. This could help to relieve perceived future pressure on the area of the river below the Diversion Dam and has the potential to create significant economic benefits. As an example, a cost – benefit analysis of the stocking of barramundi in Lake Tinaroo (QLD) indicated that each $1 spent on the program would generate a potential $31 benefit to the economy of Queensland (Makaira Pty. Ltd, 1999). There are three proposals for restocking being discussed:
1. The option of restocking Lake Kununurra every year with hatchery raised fish;
2. Using the irrigation area to facilitate the migration of barramundi for a few months at the beginning of the year (only a small modification would be needed on the D2 drain) and;
3. To build a fishway for fish to move up the Dunham River, across the Packsaddle Plain and into Lake Kununurra.
AquacultureThere are a number of small land based aquaculture operations currently present in the ORIA. There are a few management issues with mixing aquaculture and horticulture/agriculture. There are opportunities for land based aquaculture, however, the largest opportunity for aquaculture appears to be in Lake Argyle.
There is a commercial barramundi aquaculture operation in Lake Argyle. This has been in operation for a number of years and in 2000 the operation is aiming at producing between 100-150 tonne of barramundi. There is also a small commercial silver cobbler (catfish) fishery on Lake Argyle, which involves fishing for “wild” fish not fish grown in an aquaculture situation.
There is potential to expand aquaculture in Lake Argyle. In 1999 a Strategic Environmental Review examined the potential for expanding the aquaculture industry in Lake Argyle. This review found that a 2,000 tonne aquaculture industry could be supported in the lake without causing adverse environmental impacts. The report was completed for Fisheries WA to initiate the development of an intensive Barramundi industry in the Kimberley Region (LeProvost Dames & Moore, 1999). Fisheries WA has called for expressions of interest from investors and developers. Expressions of interest close in September 2000.
Knowledge Gaps-
There is an absence of adequate fish stock information and therefore the impact that fishing (both recreational and commercial) is having on the fish stock is not fully understood.
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The type of fishway required to facilitate the movement of barramundi into Lake Kununurra.
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It is not fully understood whether hatchery raised fish released into Lake Kununurra would reside in the lake or move out through the Diversion Dam gates.
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How many fish would be required to sustain the fishery in Lake Kununurra?
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What pressure would fish introduced into the lake put on current fish populations?
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How much fishing pressure is actually on the area downstream of the Diversion Dam (use numbers etc)? (Catch and effort data).
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Are other fish species numbers increasing/decreasing in the Ord River eg Mangrove Jack numbers appear to be increasing [pers comm Jane Harman])?
Protect the existing fish stock from overfishing by:
1. Understanding the carrying capacity of the fishery.
2. Encouraging recreational fishers to become responsible for protecting the fishery through becoming licensed to fish on the Ord River and to keep a log book as part of this license requirement.
3. Developing and promoting a fishery management plan for the Ord River fishery (all fishes) – building on existing attempts to set bag and size limits.
4. Preventing overfishing by individuals who do not comply with management guidelines through increased policing (which could be funded in part through the licensing scheme).
5. Researching the impact that all land and water users have on the capacity of the river to support a healthy fishery.
Strategy 2Investigate proposals relating to fish stock management on the Ord River including:
1. Examining and, if sustainable and acceptable to the Kununurra community, proceeding to stock Lake Kununurra with barramundi.
2. Examining the feasibility of a fish ladder concept for a bypass from Lake Kununurra to the Dunham River.
Strategy 3Ensure better understanding of how to sustainably fish the river for recreation by:
1. Conducting extensive publicity and education programs.
2. Involving recreational fishers, school students and the community in research, information gathering and monitoring processes.
3. Developing the log book/licensing concept to increase the information and understanding about the fishery.
Strategy 4Minimise the potential conflict between aquaculture and other land uses by:
1. Ensuring that small land based aquaculture ventures meet the environmental standards required of them.
2. Ensuring that planning schemes provide for the segregation of aquaculture and agriculture/ horticulture so as to minimise possible future conflicts.
3. Encouraging dialogue between the aquaculture and agriculture/horticulture industries on the Ord to identify and resolve potential conflicts.
4. Supporting well planned aquaculture ventures (such as those proposed for Lake Argyle and at Wyndham).
ResponsibilitiesFisheries WA have statutory responsibility for managing the fish stock and aquaculture developments, as well as conducting research and monitoring necessary to make better management decisions. They depend on local support through the East Kimberley Recreational Fishing Advisory Committee (EKRFAC).
The Shire of Wyndham East Kimberley has responsibility for town and rural planning that identifies areas for particular land use. They also have involvement in the planning for a possible bypass with fish ladder. The WA Planning Commission can reduce the potential for conflict by appropriate long term planning through vehicles such as the Kununurra Wyndham Area Development Strategy.
Department of Agriculture and local farmers need to be involved in managing the potential conflicts between agriculture/horticulture and aquaculture.
The general community, and in particular recreational fishers, have responsibilities to both participate in planning and observing the rules that apply to bag and size limits. Charter operators may be able to assist with monitoring fish populations, recording logbooks and conducting some research in conjunction with Universities.
ReferencesFishing for the Future: The essential guide to recreational fishing in Western Australia, Fisheries Western Australia – Recreational Fishing Program (Brochure).
LD West, JG Pepperell & G Waugh, (1996), Ord River Fishing Survey – Report to: East Kimberley Recreational Fishing Advisory Committee, Kewagama Research.
LeProvost Dames & Moore (1999), Kimberley Aquaculture Development Strategy, Lake Argyle Barramundi Aquaculture Industry: Strategic Environmental Review.
Makaira Pty Ltd (1999), The Translocation of Barramundi: A Discussion Paper, Fisheries Management Paper No.127, Fisheries Western Australia.
RG Doupe, C Bird (1999), Opportunities for enhancing the recreational fishery of Lake Kununurra using barramundi Lates calcarifer: A review, Proceedings of the Royal Society of Queensland, In Press.
Robert Tregonning, Fisheries WA, pers comm, March 2000.
T Thorne (1997), The aquaculture of non-endemic species in Western Australia – Redclaw Crayfish – Cherax quadricarinatus, Fisheries Management Paper No.100, Fisheries Department of Western Australia.
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To develop a recreational and commercial use plan for the Ord River within 3 years
All of the waterways around the town of Kununurra are popular for recreational activities (including Lakes Kununurra and Argyle, and the Lower Ord River). These recreational activities range from water skiing and sailing to barramundi fishing, canoeing and general boating.
One of the most popular of these activities is recreational fishing. The most popular fish to catch are barramundi. These are only located in the Lower Ord (as the irrigation supply reservoirs act as a barrier to the upstream migration of this species) and therefore there is significant fishing pressure on this section of the river (Doupe and Bird, 1999).
Other recreational activities are spread out across the three waterways with most of the water skiing and canoeing limited to Lake Kununurra and general boating and sailing carried out on Lake Argyle.
Current StatusCurrently there is a community group focused on managing the access to a section of the river below the Diversion Dam. The Lower Ord Community Advisory Committee (LOCAC) focuses on the old Noogoora Burr quarantine area, and more recently areas near Buttons Gap. This group works with station management and is concerned with providing facilities – such as toilets, rubbish bins and boat ramps.
This group helped to initiate the Lower Ord Management Strategy. This strategy outlines where boats can be launched, location of other facilities (such as toilets), and permit costs for utilising the facilities, as well as general safety and fishing information (brochure available from SWEK offices).
RubbishIn the Ord River Fishing Survey conducted in 1996 (West et al, 1996), there was concern raised by 23% of the respondents in regards to rubbish along the river. Of particular concern is non-biodegradable litter such as aluminium cans, fishing line, disposable nappies and plastic bags. At many of the popular fishing and recreational sites there is rubbish present. This rubbish is hazardous to native animals as well as being unsightly and ruining the “experience” that can be gained from the area.
There is a small group of community members who are making an effort to reduce the impacts of rubbish on the environment around the area. This group is called Society of Litter Eradication & Education for Kununurra (SLEEK). There was one very successful clean up in 1999 and more are planned for the future.
CumbungiCumbungi growth along the river edges emerged as the primary concern across all user groups interviewed as part of the Ord Fishing Survey (1996). The main concern raised in this report and through Ord Land & Water community meetings was that the growth of Cumbungi increased the hazards posed by crocodiles and increased the risk of conflict between crocodiles and recreational river users.
There is also concern that cumbungi is not being well managed on Lake Kununurra and its spread is beginning to affect recreational use of the lake. With possible future changes in water levels in the Lower Ord towards the latter part of the dry season, the impact of flushing cumbungi from Lake Kununurra into the Ord River may increase.
Other groups in the community see the cumbungi as playing an important role in bank stabilisation and nutrient filtering of run-off prior to it entering the waterways.
CrocodilesConcerns about safety and crocodiles in the Lower Ord have increased as the use of this area has increased. Lake Kununurra and Lake Argyle are both crocodile control zones (CCZ) (Section - Native Plants and Animals). Below the Diversion Dam the Ord River is divided into crocodile management zones (CMZ). These zones extend to Parry Lagoons Nature Reserve and the Ord River Nature Reserve. Generally salt-water crocodiles are left to their own devices in these parts of the river, unless licenses are issued for stocking farms or individual animals are deemed to be problem crocodiles.
If there are problem crocodiles in popular areas or where they may have an impact on humans or stock, such as River Farm Road, they are generally trapped and removed. In the future there may need to be a specific management plan for crocodiles in the Ord River near River Farm Road.
BoatingPower boats: Increased powerboat activities may lead to greater leakage of oil and fuel residues into waterways. This may not cause problems in areas where the flow rates are high, however, it could have an impact in the shallow wetland areas where mixing and throughput is reduced (Watkins et al, 1997). There is currently a new “breed” of two-stroke motors referred to as direct injection two-strokes. These motors greatly reduce hydrocarbon emissions and increase fuel efficiency and operating characteristics (up to 80% reductions in emissions). Four stroke engines are another low-emission high-fuel efficiency alternative (www.nmma-medialink.com).
General boating: Uncontrolled access to waterways can result in serious disturbances such as the crushing and trampling of native vegetation, increasing weed growth, rubbish spills, soil compaction and fires (Water and Rivers Commission, January 2000). This highlights the need for management of public access to the river.
Increases in canoeing and other outdoor activities that involve camping between the two dams could cause disturbances to wildlife breeding sites. Turtles, crocodiles and water monitors favour sand banks as areas for breeding sites. These sandy areas are also favoured by campers (Watkins et al, 1997).
There have been a number of proposals for houseboats for Lake Kununurra. These proposals need to be assessed in depth, and investigations into their possible impacts need to be completed prior to any decisions being made.
Knowledge Gaps-
Who is responsible for ensuring rubbish collection at popular locations?
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Should we have rubbish collection facilities at popular locations or should the message be – take your rubbish home?
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How many people actually use the river for recreational purposes and what pressures are they placing on the river?
Reduce rubbish and other pollution of the river by:
1. Involving the whole community in developing guidelines for river management including:
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active rubbish management (a take your rubbish home campaign),
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developed and serviced access points,
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promotion of modern two stroke or four stroke outboard motors to minimise possible oil pollution.
Reduce the pressure on the river from recreational use by:
1. Encouraging the development of management guidelines for all types of recreational use of the river including – general boating, camping, houseboats, etc.
2. Ensuring these guidelines are developed in conjunction with the community and that they are enforceable.
3. Managing high use areas such as boat ramps and other access points.
Strategy 3Improve the understanding of issues associated with recreational use of the river by:
1. Conducting information and education programs, for example using a log book as a source of information on native and feral species, fish species, rubbish management, etc.
2. Involving all recreational groups in planning for sensible sustainable recreational use.
3. Encouraging recreational user groups to manage the areas they use.
4. Developing and implementing best management practices for recreational use of the river and lakes.
Strategy 4Improve safety on the water by:
1. Recognising boating codes of practice or ethics.
2. Suggesting regulated speed limits at specific locations along the river, launching areas and designated use areas.
3. Maintaining awareness of crocodile presence in waterways.
ResponsibilitiesRecreational use of the river includes a number of areas of state agency jurisdiction including Department of Transport for boat licensing and the Water and Rivers Commission for river health. The Shire of Wyndham East Kimberley have involvement with the Lower Ord Community Advisory Committee and a responsibility, along with the Tourist Bureau, for providing visitor information. Fisheries WA has responsibility for fish stock management, research, education, enforcement and monitoring associated with the recreational and commercial fisheries.
Tour operators have a responsibility to both avoid damage to the river and its environs and to spread the message about better management of recreational use. The Lower Ord Community Advisory Committee (LOCAC) has specific responsibility for advising on the management of the lower reaches of the Ord where there are a number of competing uses and issues relating to access, rubbish control and people management.
Conservation and Land Management have expertise in managing natural resources and recreational use so should be involved in the planning and execution of best management practices.
The general community and in particular the recreational user groups and sporting clubs need to be involved in ensuring sensible use and should form the front line for spreading the word about sustainable use.
Traditional Owners and other Aboriginal groups also have a role in developing management plans and providing the necessary information and education links to Aboriginal people.
ReferencesFrequently asked questions about Recreational Boating Frequently asked questions about Recreational Boating, National Marine Manufactures Association's Information Centre for Boating Writers and Consumers (www.nmma-medialink.com/frequent.htm).
LD West, JG Pepperell & G Waugh, (1996), Ord River Fishing Survey – Report to: East Kimberley Recreational Fishing Advisory Committee, Kewagama Research.
RG Doupe, C Bird (1999), Opportunities for enhancing the recreational fishery of Lake Kununurra using barramundi Lates calcarifer: A review, Proceedings of the Royal Society of Queensland, In Press.
Watkins, D., Brennan, K., Lange, C., Jaensch, R., Finlayson, M., (1997), Planning for Ramsar Sites in the Kimberley Region of Western Australia, Wetlands International – Oceania, Environmental Research Institute of the Supervising Scientist Consultant.
Water and Rivers Commission (January 2000), Protecting Riparian Vegetation, Water Notes, WN10
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To prevent further damage and modification to the natural riparian vegetation
Riparian areas are those close to the margins of rivers, wetlands, streams and other drainage lines whose characteristics are determined by the presence of water. These areas are important as they act as areas of refuge for animals during dry periods, and often support a highly diverse and fragile ecosystem. Maintaining diversity of these ecosystems is important so the ability for these ecosystems to adapt to change is not lost.
Riparian land is often highly productive and often plays an important role in the lifecycle of many native animals and plants (Tubman (Ed), 1996). By its very nature riparian land is fragile. Its productivity also makes it vulnerable to overuse and to practices which cause it to deteriorate (Tubman (Ed), 1996).
The riparian areas of Lakes Argyle and Kununurra (and the Lower Ord Floodplain) are important because they are listed as Ramsar wetlands. This means that they are seen as important internationally as migratory bird habitat and must be managed so as to maintain their ecological character (James, 1997).
Current StatusThe more uniform river flows since the dams have been built has altered the location and nature of the riparian areas of the Ord River system.
Along the Ord River there are now four sections with quite different flow regimes that have developed unique riparian areas.
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Above Lake Argyle – where the river is still seasonal – with flood pulses that maintain a near original riparian zone.
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Lake Argyle – where the water level fluctuates, the old riparian vegetation has been drowned and a new shoreline has formed with little or no vegetation.
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Lake Kununurra – where the water level is stable the old riparian vegetation has been drowned and a new shoreline formed with reed beds and a more luxuriant riparian vegetation.
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Below the Diversion Dam –there are permanent flows with rare peak flood flows and the fresh water/salt water interface is further downstream. A new and more luxuriant riparian vegetation has developed in this portion of the Ord River system.
The diversity of plants and animals in all these areas has changed since the construction of both dams. The riparian areas around Lake Kununurra have increased in diversity as a result of having stable, permanent water levels. The shorelines of Lake Argyle may have lost diversity as a result of the fluctuating water level.
WeedsWeeds are currently one of the primary issues of concern in riparian zones. In areas where there has been disturbance by people or stock weeds can proliferate (Tubman (Ed), 1996). There are now areas of Bellyache Bush on Lisadell Station (upstream of Lake Argyle), and a small number of these plants have been found at Buttons Gap – downstream of the Diversion Dam. Other weed species such as Parkinsonia and Noogoora Burr are common throughout parts of the catchment while plants such as Sorghum and Leucaena pose significant threats as they escape from the agricultural area. Many of the weed species are not adapted to flooding (whereas native species are) and therefore if flood events are rare these weeds can spread and become dominant (see Section - Weeds).
Feral AnimalsFeral animals are not seen as a large threat to the riparian areas at present. There are a number of small populations of feral pigs, however these numbers are not high enough to warrant a formal control program (see Section – Pest and Feral Animals).
Stock AccessIntensive use of the river for stock watering has the ability to cause destruction of riparian vegetation and bank erosion (Water and Rivers Commission, 1997). However, where the grazing pressure is greatest, in the area downstream of the Diversion Dam, the impact from stock appears to be localised. The heaviest impact from stock is in areas where access to the river is restricted by steep banks and the pressure is increased on areas where the access is possible (Tony Start pers comm).
It is not necessary to permanently exclude animals from riparian lands, but it is important to control their movement and to manage grazing pressure (Tubman (Ed), 1996). See Section 3.6 – Stock Access for the management regime in place for the area of the river below the Diversion Dam (Carlton Hill and Ivanhoe Stations).
Current Projects Integrated overview of values, uses and modifying processes in the Ord River’s riparian zone.This is a Tropical Savannas CRC project and the project leader Dr Tony Start is based at Conservation and Land Management in Kununurra. The project seeks a better understanding of the role of riparian systems, the margins of wetlands, rivers, streams and other drainage lines in the sustainable land management of tropical savannas.
Dr Karl-Heinz Wyrwoll is supervising PhD and honours students from the University of WA (all from the Geography Dept) who are looking into the hydrological aspects of sediment mobilisation, transport, and deposition. This fits in with the biological component of the project.
PhD - Factors Affecting Riparian Vegetation Recruitment on the Ord River.Neil Pettit from Edith Cowan University.
Productivity and water flow regulation in the Ord River of north-western Australia.The Water and Rivers Commission and two Perth Universities are involved in this project. This project will provide the basis for the determination of Ecological Water Requirements and the Environmental Water Provisions for the Lower Ord River (this is required for the Water Allocation Plan). The timeframe for project completion is 2002.
Resilience of the Ord River to Irrigation ReturnThe Water and Rivers Commission and two Perth Universities are working together to develop this project. The project is yet to be finalised (March 2000) and is subject to funding being approved.
Knowledge Gaps-
The impact of possible future change in the water regime on the riparian areas below the Diversion Dam.
Reduce the impact of use on the riparian areas by:
1. Educating the public about the importance of the riparian zone.
2. Limiting user access to particular serviced access points.
3. Including the riparian areas in an overall river management strategy.
Strategy 2Prevent further damage and modification to the natural riparian vegetation by:
1. Developing and implementing a river management strategy which includes controlling the spread of weeds and feral animals (particularly pigs and cattle in the riparian zone).
2. Managing cattle grazing access to parts of the riparian zone by exclusion fencing in areas where they are having a negative impact.
Strategy 3Monitor changes in the riparian zone ecology by:
Developing and implementing monitoring systems (both scientific and general observations) to follow changes in the condition of the riparian zone
ResponsibilitiesThe health of the riparian zone is linked to the health of the river so those with responsibilities include Water and Rivers Commission, the Lower Ord Community Advisory Committee and the Shire of Wyndham East Kimberley.
Others with expertise that should be involved include Conservation and Land Management, station Management and the Ord River Irrigation Area LCDC. It is important that the Management of the riparian zone be linked to river Management and water allocations as minor changes in flow can create major changes in the riparian zone.
ReferencesDr Tony Start, Conservation and Land Management
James, R (1997), A Directory of Important Wetlands in Australia – The Ramsar Convention in Australia – 25 years on. Wetlands and Migratory Wildlife Unit, ANCA.
Paula Deegan, Water and Rivers Commission.
Water and Rivers Commission (1997), State of the Northern Rivers
Wendy Tubman (Ed) (1996), Riparian Management - Managing Riparian Land, Land & Water Research & Development Corporation.
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To develop a plan to allocate water from the Ord River to competing uses including he environment. To develop the plan with full community involvement within 5 years.
The Water and Rivers Commission is responsible for ensuring the sustainable Management of the State’s surface and ground water resources. In order to achieve this, water allocation plans are required for each “water Management system” to define the amount of water to be made available for each use.
Water allocation plans define the amount of water that can be legally diverted from river systems and ground water aquifers. Water allocation plans must take into account: environmental water provisions, ecological water requirements, sustainability, irrigators, recreational users and other potential users.
Allocation plans are implemented through the Rights in Water and Irrigation Act (1914). Licenses formalise the allocations and are subject to conditions necessary for good Management of the resource. The state’s water allocation system is evolving to meet the requirements of the Council of Australian Government’s Water Reform Framework Agreement and licensing is to become the means to identify water allocations and their holders (WRAP 2, 1999).
The water allocation plan aims to provide strategic direction by identifying future development and associated demands for water while protecting the supply of water necessary for the environment. Environmental approval of developments (such as Ord Stage 2) is subject to the determination of an acceptable amount of water to support ecological and environmental objectives for the Ord River.
Current StatusThe allocation plan for the Ord is currently in draft form. The Draft Interim Water Allocation Plan for the Ord River was presented to key stakeholders and released for public comment through the Environmental Protection Authority (EPA) in 1999. Public submissions were sent to the EPA and the advice from the EPA was provided to the Water and Rivers Commission in December 1999.
The comments from the EPA suggested the need to:
(a) review the basis for determining the interim Environmental Water Provisions, and
(b) to take into account the current flow regime that has prevailed for the last 30 years. The EPA also recommended the development of an expert panel to guide the allocation process.
There is concern in the community regarding what the water levels are going to be downstream of the Diversion Dam in the future, in particular when Ord Stage 2 is fully developed. This area of the river is popular for recreation and a number of tourist operators run businesses in the area. There are concerns that reductions in water levels may have an impact on the riparian areas of the river (as they are today) and the ability to safely access this area.
Irrigators in the ORIA Stage 1 area are keen to guarantee the supply of water for irrigation for the future.
Current ProjectsProductivity and water flow regulation in the Ord River of North Western Australia.
The Water and Rivers Commission and two Perth Universities are involved in this project. This project will provide the basis for the determination of Ecological Water Requirements and the Environmental Water Provisions for the Lower Ord River (this is required for the Water Allocation Plan). The timeframe for project completion is 2002.
Knowledge Gaps-
How much water is required for “environmental flows”?
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Who “pays” for the environmental flows and for flow to enable recreational use of the river?
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What is the “dollar value” of the water (what is the actual cost of the water)?
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What impact will a changed water regime, resulting from greater diversion of water for Stage 2, have on the downstream environment, as well as the ability to utilise the river for recreation and tourism?
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What impact will the lower flows have on the water quality in the river?
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When will the changed water regime will begin (determines the lead-time to implement changes in Management – for tour operators, farmers etc)?
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What impacts will lower water levels have on Cumbungi in the Lower Ord?
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Will it be possible to simulate flood pulses in the river that are big enough to have an impact on the health of the river system?
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What is the size and probability of flood pulses that come from the Dunham River catchment?
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What impact will lower water levels have on crocodile populations, movement and recreational user safety?
Develop understanding of the environmental requirements of the river downstream of the irrigation area by:
1. Encouraging well planned research to determine the Environmental Water Requirements and the likely impacts of changed river flows on the riverine and adjacent riparian environment.
2. Monitoring these environments and providing real time feed back that enables Management of river flows to be based on up to date information.
Strategy 2Develop a Water Allocation Plan by:
1. Taking into account the requirements of:
(a) the downstream environment
(b) Stage 1 Irrigation Area
(c) Ord Hydro Pty Ltd
(d) Recreational users
(e) Other potential water users including Stage 2.
2. Ensuring involvement of key stakeholders in the development of the Water Allocation Plan (including Ord Irrigation Co-op, Stage 1 irrigators and tour operators who operate in the area)
ResponsibilitiesWater and Rivers Commission has legislative responsibility and is therefore the lead agency for the allocation of water. They have a responsibility to ensure local stakeholder involvement in the allocation process.
Water users, including irrigators, tour operators and recreational users of water, and Ord Irrigation Cooperative have a responsibility to ensure that they have input into the allocation process. The general public and other river users complete the list of potential stakeholders that need to be involved in the planning process.
ReferencesDraft Interim Water Allocation Plan, Ord River Western Australia. Water Resource Allocation and Planning series, WRAP 2 May 1999.
Draft Interim Water Allocation Plan, Ord River, EPA bulletin 965 December 1999
Leith Bowyer, Water and Rivers Commission, Kununurra
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Reduce the off farm exports of chemicals nutrients and soil into the Dunham River during the dry season by 50% within 5 years
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Within ten years develop a full catchment plan for the Dunham River that involves all the stakeholders
This short section of the river consists of a number of deep pools and rock bars, which reduce the flow of water and has the potential to cause water quality problems associated with slow flowing systems (such as oxygen depletion in the deep pools).
To some extent the level of the Ord River controls the level in this section of the Dunham River. When the Ord River water level is high, less water can leave the Dunham River leading to water backing up or being trapped in the Dunham and much reduced flow rates.
Irrigation tail water from the Packsaddle Irrigation Area enters Packsaddle Creek, which means that there is flow in the creek, and therefore into the Dunham River, throughout the dry season.
As the Dunham River is a seasonal river, the water level often increases during the wet season, depending on rainfall. This can lead to a flood pulse moving down the river and into the Lower Ord River. This is the main alteration in flow for the Lower Ord, as throughout most years the water released from the Diversion Dam remains relatively constant. Major rainfall events and rare “big” wet seasons can result in very large river flows that generate major flood pulses in the lower Ord.
Current StatusThere are a number of sites in the Dunham (and Packsaddle Creek) that are sampled as part of the the program to sample water quality. During 1998 there were a number of “hits” of pesticide in both the Dunham River and Packsaddle Creek. A number of these hits were very high (see Section – Surface Water Quality). During 1997 there was a fish kill in the Dunham River.
A bypass is being discussed as a possible means of allowing water from Lake Kununurra to flow into the Dunham River (via Packsaddle Creek). This will increase the flow of water in the lower reaches of the Dunham River as well as reducing the flow in the Ord. The overall effect should be an improvement in the quality of the water in this problem section of the river (through a diluting effect as well as an increased water flow and thus more effective flushing). There is a feasibility study under way for this project.
This bypass also has the potential to act as a fish ladder therefore allowing barramundi to enter Lake Kununurra (see Section – Fish Stock Management).
Projects Under Way-
The feasibility of building a bypass from Lake Kununurra to the Dunham River via Packsaddle Creek is being studied.
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Will the bypass idea achieve the desired outcome? Will it enable barramundi to migrate?
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What can be done to improve the quality of the water in the river?
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What is the best way to manage the Dunham River?
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What impacts is it having on the water quality in the Ord River?
Improve the quality of water flowing through the Dunham River by:
1. Revegetating the catchment of the river thus reducing sediment loads during wet season flows.
2. Providing cleaner water from the irrigation system during the dry season by
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Improving irrigation and farm Management to ensure cleaner drainage water,
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Installing and managing silt traps prior to drainage water leaving farms,
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Developing constructed wetlands on the Packsaddle drainage system to filter water prior to its entry into the Dunham River,
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Examining the feasibility and sustainability of bypassing water from Lake Kununurra to the Dunham River to dilute any drainage water from the irrigation area.
3. Managing the water flows in the Ord to improve the Management of the Dunham River during the dry season.
Strategy 2Reduce the amount of drainage water entering the Dunham during the dry season by:
1. Encouraging a reduction in the amount of tail water leaving irrigation farms by using ideas raised in Section – Irrigation Management.
2. Encouraging investigation into reusing tail water where appropriate.
Strategy 3Provide monitoring and research information to enable adjustments to Management by:
1. Gathering sufficient research information to quantify the flows and requirements to maintain a healthy Dunham river.
2. Regularly monitoring water quality in the Dunham river (the whole river not just the area below the confluence of Packsaddle Creek and the Dunham River).
3. Ensuring that all stakeholders have access to monitoring information in a manner that enables better Management decisions to be made.
ResponsibilitiesThe Water and Rivers Commission is responsible for river health and will be responsible for providing research and long term river monitoring information. The Water Corporation and Ord Irrigation Cooperative have responsibility for managing the irrigation water and drains, so will be integral to any Management actions resulting from research and monitoring. The Ord Irrigation Cooperative is also responsible for monitoring water quality in drainage water.
Packsaddle farmers have the greatest responsibility to improve Management, install silt traps and develop recycling systems to reduce pressure on the Dunham. The SWEK has a role in managing the process to examine the potential for a bypass from Lake Kununurra. The Ord River Irrigation Area LCDC and the Halls Creek East Kimberley LCDC should be involved in helping to develop and implement Management plans that will reduce sediment loads in the river and drainage systems.
ReferencesData provided by Water and Rivers Commission.
In the past the main land use in the catchment of the Ord River was grazing cattle. Initially, the river was used as the source of water for stock as there were no artificial water points in place. Much of the catchment area above Lake Argyle has been destocked or access to the river controlled by fences. Downstream of the Diversion Dam cattle are still using the river as a water source.
Current StatusCarlton Hill and Ivanhoe Stations are situated along the river downstream from the Diversion Dam. To control erosion and better manage the parts of the stations with river access, all the paddocks that have river access are being fenced. These paddocks are destocked every second wet season to allow the grasses time to grow and set seed. Initially these areas were planted with buffel grass, however this is no longer practiced.
Since the station Management has been using the program of controlled grazing in the river areas, the native grass species in these areas have proliferated (Claire Warriner Carlton Hill Station pers comm).
Generally the impact of stock on the riparian areas of the river is very localised (see Section – Riparian Areas).
It is not economically feasible to fence off the river completely as this would mean having to provide artificial watering points and the loss of some of the most productive grazing areas (Geoff Warriner – Manager Carlton Hill Station pers comm).
Knowledge gaps-
Which grass species are dominant in the riparian areas.
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The levels of silt that are moving as a result of stock access.
Determine the impacts of stock on the river by:
1. Installing and regularly recording monitoring sites
2. Working with station Management to increase the information on stock impacts on the river
Strategy 2Manage the impacts of grazing stock by:
1. Further developing grazing Management systems aimed at reducing the impact of stock on riparian vegetation.
2. Reducing the stocking pressure on areas adjacent to the river.
3. Strategic fencing that restricts stock access while enabling limited access for water.
4. Providing alternative watering points.
ResponsibilityThe main responsibility lies with the managers of Carlton and Ivanhoe stations to continue to improve Management of those areas along the river that are impacted by stock. They will need support from research and development agencies like Department of Agriculture and Water and Rivers Commission. The Halls Creek East Kimberley LCDC could also provide support for the development of improved grazing Management.
ReferencesClaire and Geoff Warriner, Managers Carlton and Ivanhoe Stations.
There is float water from the M1 channel and some drainage water from the northern end of the Ivanhoe Plain (Cave Springs) that runs into drains HD3 and D8 and then out into the bush. There is concern about the influence that this water is having on the area.
Current StatusThe area under question will be part of the proposed Stage 2 development. The soil types in this area are Aquitaine clays. These soils are reasonably impermeable when wet and therefore the risk to the ground water in the area is considered to be low. The water running out of the D8 drain is tested as part of the program to monitor water quality (Section - Surface Water Quality).
There are a number of options for dealing with these waters once the Stage 2 area is fully developed, however these have not yet been evaluated ( Philip Pyle, pers comm 1999).
Knowledge Gaps-
What will happen to the water until Stage 2 is developed?
Reduce the amount of system float water leaving Stage 1 by:
1. Improving the Management of the irrigation water to minimise the amount of water leaving the system.
2. Investigate the feasibility of recycling water at the end of the system.
3. Ensuring this water becomes a part of the supply system for Stage 2.
Strategy 2Better understand the likely impact should Stage 2 not go ahead by:
1. Monitoring impacts on vegetation, wildlife and ground water.
ResponsibilitiesThe managers of the irrigation system (Water Corporation and Ord Irrigation Cooperative) have the major responsibility in this area. The proponents of Stage 2 need to be aware of the need to capture any excess water from the existing irrigation area. There may be a project for the Ord River Irrigation Area LCDC to establish a monitoring system for the wetland area created by the excess water.
ReferencesLetter from Philip Pyle, Project Manager, Water Corporation (19th July 1999).
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Develop, with community involvement, a plan to manage flooding of the Ord River by December 2000.
The Ord River is now a controlled river. The Kununurra Diversion Dam was finished in the early 1960s and Lake Argyle was completed in 1973. Prior to this time the Ord River was a seasonal river, drying up during the dry season and flowing according to rainfall during the wet season.
There is a State Framework for Floodplain Management in Western Australia and there is a flood emergency plan for the Ord River that identifies agency responsibilities. Flood warning information comes through the Bureau of Meteorology. This information is available at www.bom.gov.au/weather/wa. This is updated regularly.
Current StatusThe 1999/2000 wet season has highlighted the need for flood management, despite the Ord River being a controlled river system. Flows during this time reached record highs and several management decisions were made that had adverse impacts on upstream and downstream water users.
The Water Corporation operates the two dams. When flood flows enter Lake Argyle a stable level is maintained in Lake Kununurra to prevent flooding of the ORIA and township.
The flood flows of the 1999/2000 wet season through the system were up to 1000m3/s (with peak inflow information not yet available from the gauging station at the Old Ord Homestead). A significant flow down the Dunham River reached magnitude of about 2,000 m3/s. The Lower Ord is likely to have had flows well in excess of 4,000 m3/s. These flows for both the Ord and Dunham rivers are likely to be the highest flows ever recorded. Further information on peak flows will be available in the near future.
Knowledge Gaps-
What impacts does flooding have on the environment below the Diversion Dam? (this is part of the EWR/EWP study mentioned below).
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How do we best manage flood conditions to minimise the impacts on the upstream and downstream users and the environment?
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What impact does flooding have on users (agriculture, tourism, recreation etc) of the system?
This project will provide the basis for the determination of Ecological Water Requirements and the Environmental Water Provisions for the Ord River (this information is required for the Water Allocation Plan). The Water and Rivers Commission and two Perth Universities are carrying out the project. The timeframe for completion of this project is 2002.
Strategies Strategy 1Minimise the impacts of flood events on water users by:
1. Developing a flood management strategy that includes:
Strategy 2a) A communication strategy to ensure effective, timely communication between the community and relevant government agencies,
b) Timely monitoring and forecasting to provide information for action to be taken by the responsible agencies.
Incorporate a coordinated flood management strategy in the planning for the Ord River.
ResponsibilityThe responsibility for flood management lies with the Water and Rivers Commission and the Water Corporation. The hydrology information required to monitor flood flows is also the responsibility of the above agencies.
ReferencesA Framework for Floodplain Management in Western Australia with a focus on Carnarvon. (July, 1998), Report of the Ministerial Taskforce into Floodplain Management to the Minister for Water Resources, ISBN 0-7309-7423-5.
Data provided by the Water and Rivers Commission, Kununurra.