masthead

WeConnect - Your Connection to Our Strategies

Goulburn Broken Catchment Management Strategy

get started

Regional Catchment Strategy 2013-2019

Water

Printer-friendly version

 Waterways, wetlands, floodplains and groundwater aquifers are an integral part of the Catchment providing many environmental, social and economic services. They underpin livelihoods, support agriculture and urban centres; contain significant flora and fauna habitat; have high recreational and aesthetic values, and are central to the culture of the Traditional Owners. There are two major river basins in the Catchment.

Goulburn River Basin

The Goulburn River Basin is Victoria’s largest, covering 1.6 million hectares or 7.1 per cent of Victoria. The Goulburn River is 570 kilometres long, flowing from the Great Dividing Range upstream of Woods Point to the Murray River east of Echuca (Figure 12).

Stream flow along the Goulburn River has been modified by two major features, Lake Eildon and the Goulburn Weir. Lake Eildon is located in the river’s upper catchment. It has a capacity of 3,330 gigalitres, with 91 per cent of water released, on average, diverted for irrigation and urban purposes (G-MW 2012). With such a large storage capacity, operation of the lake fully regulates downstream flows in all but wet years (GB CMA 2008).

The Goulburn Weir is approximately 235 kilometres downstream of Lake Eildon, north of Nagambie. It holds 25 gigalitres and is usually held close to full capacity to facilitate the diversion of water to supply Waranga Basin and the irrigated lands of the Central Goulburn Irrigation Area. Waranga Basin holds 432 gigalitres and is used to store winter and spring flows from tributaries downstream of Lake Eildon to be used across the irrigated region from Tatura to Echuca and into the North Central Catchment.

Broken River Basin

The Broken River Basin is 772,386 hectares or 3.4 per cent of Victoria’s total area. The Broken River is a tributary of the Goulburn River (Figure 12). The basin also includes the catchment of the Broken Creek that diverges from the Broken River west of Winton Wetlands and flows north-west to the Murray River (Figure 12).

Flow in the Broken River is extremely variable between seasons and years. Two major storages have been constructed within the catchment, Lake Nillahcootie and Lake Mokoan. Lake Nillahcootie is located in the Broken River’s upper catchment and stores flows to provide water for irrigation, urban and stock and domestic use. Lake Mokoan was constructed in 1971 but was decommissioned as an active reservoir in 2010 and its natural wetland habitat is being restored.

Waterways across the Catchment are shown in figure 3.3.

 Figure 3.3: Priority waterways of the Goulburn Broken Catchment

Floodplains

Natural floodplains across the Catchment have an important ecological function with floods supporting vegetation and wetlands on the floodplain as well as the river channel ecology. Floodplains have been highly modified with built infrastructure to  support and protect urban centres and agricultural production, as well as levees to protect these areas  from flooding impacts. River regulation has altered flood frequency and patterns.

Across the Goulburn Broken Catchment, some 5,800 square kilometres of floodplain areas have been mapped up to the extent of the 100-year Average Recurrence Interval (ARI) flood.

Wetlands

Wetlands exist at the interface between land and water and play a key role in the maintenance of the hydrological, physical and ecological health of river systems. Wetlands perform numerous vital functions including water purification, nutrient processing and retention, maintenance of watertables, flood protection, erosion control and groundwater recharge. They also provide habitat, refuge, and breeding and nursery areas for many species. Wetlands are also valued for recreation by many communities.

Over 2,000 wetlands have been mapped and classified covering approximately 86,000 hectares of the Catchment. These wetlands include large permanent lakes, floodplain billabongs, small spring soaks, alpine bogs and shallow freshwater depressions. Most wetlands are ephemeral, occur on private land, are less than 10 hectares in size and occur on the region’s floodplains (Figure 13).

Of these a number have been formally recognised for their conservation significance. These include the internationally significant Barmah Forest Ramsar site, 10 wetlands of national significance listed in the Directory of Important Wetlands of Australia (DIWA) and 111 wetlands of bioregional significance identified for the National Land and Water Resource Audit (Bioregional). In addition, a large number of wetlands support state and nationally threatened species and communities, and birds listed on international agreements and conventions.

The location of wetlands across the Catchment is shown in figure 3.3.

Figure 3.4: Priority wetlands of the Goulburn Broken Catchment (this map has been updated)

Groundwater aquifers

Groundwater is found in aquifers across the Catchment; layers of underground sediments or fractured rock. There are a number of significant deep and shallow groundwater aquifer systems that are varied in their character and connectivity.

In the upper and mid parts of the Catchment, fresh groundwater is primarily used for domestic and stock consumption. In the lower Catchment groundwater is used to support agricultural production, as well as stock and domestic supply.

More saline shallow aquifers across the lower floodplains are also managed as a threat to prevent degradation of land productivity, natural assets and downstream assets including the River Murray.

Many ecosystems rely on groundwater for some or all of their water requirements including terrestrial vegetation, waterways, wetlands and their dependent fauna. Except for rivers and streams that have groundwater sustained base flows, these are known as groundwater dependent ecosystems (GDEs). To date they have not been broadly identified or mapped across the Catchment. The impact of changes in groundwater quantity and quality on GDEs is determined by the degree and nature of their groundwater dependency.

Current condition

River and wetland condition in Victoria is assessed using the Index of Stream Condition (ISC) and the Index of Wetland Condition (IWC). These measures assess factors such changes in hydrology, water quality, form and condition, vegetation health and species diversity. The ISC and IWC can be used to classify rivers and wetland ecosystems into the following condition states outlined in Table 6.

In 2004, the ISC assessment of selected river reaches in the Goulburn and Broken basins indicated that most are in moderate (54 per cent) and poor (23 per cent) condition, with a small proportion in very poor condition (6 per cent). About 11 per cent of reaches were assessed to be in good condition and five per cent in excellent condition.

Since European settlement the extent of some wetland types have declined by 20 to 60 per cent in the Catchment. These have predominantly been smaller and less permanent wetlands as they are more susceptible to threats such as drainage and water regulation. Conversely, the construction of artificial impoundments has increased the total extent of wetlands in the region since European settlement.

Since 2009 IWC assessments have been carried out on 116 wetlands across the region. Results indicate that most are in good (38 per cent) and moderate (40 per cent) condition, and a small proportion are in excellent (6 per cent), poor (15 per cent) and very poor condition (<2 per cent). The fact that about 57 per cent of wetlands are in moderate to very poor condition indicates that many wetlands in the region are still subject to threatening processes. The results also indicated that wetlands on public land are generally in better condition than those on private land, although there are still examples of wetlands in good condition on private land.

Table 6: Waterway values and condition states

Significant threats

The four drivers of change identified in the RCS; climate variability, land-use change, water policy reform and the increasing farm production provide both threats and opportunties to water.  Specific activities and processes that threaten the condition of waterways, floodplains, wetlands and groundwater which can result from one or more of the drivers, include:

  • Catchment clearing
  • groundwater extraction
  • pest plant and animal invasion
  • snag removal
  • stock access to riparian zones
  • waterway regulation and flow diversion
  • urban and agricultural development, including irrigation

These activities and processes are linked to:

  • physical degradation of riverbanks and channels
  • reduced water quality and temperature
  • loss of instream and riparian habitat and complexity
  • modified flow and flood regimes
  • decline in the diversity and abundance of biodiversity
  • reduced primary production and nutrient cycling
  • changes to river and floodplain morphology
  • disruption of lifecycles and breeding cues
  • high watertables and salinity
  • waterlogging
  • reduced groundwater resources

Whilst the ecological value of floodplains is well recognised, they also pose a significant flood risk to the many town centres established within floodplain areas. Examples of these centres include Shepparton, Seymour, Benalla, Euroa, Numurkah and other centres on floodplains and valley floors. Floods also impact on agricultural production.

In monetary terms, the average annual flood damage (AAD) cost within the Goulburn Broken Catchment is well over $30 million per annual (URS 2001). In addition to monetary losses, there are significant recovery issues associated with human suffering. The AAD determined in 2001 would have increased in light of inflation (CPI), additional infrastructure build on floodplains, greater population, etc. It is anticipated that AAD increases could double to $60 million per annum (pers. comm. Guy Tierney).

Climate variability, leading to reduced rainfall, and extraction pressures are threats to groundwater aquifer assets, in terms of water availability and quality.

Management

The monitoring and management of water assets across the Goulburn Broken Catchment is undertaken by multiple organisations including Goulburn-Murray Water, Goulburn Valley Water, Evironmental Protection Authority, DPI, DSE and Local Government as well as the Goulburn Broken CMA.  These, and other organisation partner with community groups and individual landholders to undertake a range of natural resource and community based activities, including fencing, revegetation, pest plant and animal control, resnagging and monitoring to protect water assets across the Catchment.  These onground works are complemented by projects including the development and implementaiton of environmental water delivery plans (with the Commonwealth and State Environmental Water Holdersand through multi-agency forums such as the River and Water Contingency Planning Group and the Regional Water Quality Forum) and floodplain management and planning. 

In the Agricultural Floodplains SES, infrustructure including grounwater pumps, surface water drains and the undertaking of intensive groundwater and drain monitoring is seeking to protect wetlands and rivers from rising groundwater and high salinity levels.

At a local level, community involvment in the management of water across the region continues to be strong with program such as WaterWatch  and RiverConnect continuing to deliver a highly successful community education program with activities being integrated into natural resource management programs.   Works undertaken by landholders and the community to primarily to improve the Catchment's terrestrial biodiveristy and land assets can also improve the condition of water assets.

Guiding current thinking

The Goulburn Broken CMA’s Regional River Health Strategy Addendum 2010, the Water Quality Strategy 2002 and the Floodplain Management Strategy 2002 provide a basis for action on water. Groundwater management plans or water supply protection areas have been developed to manage extraction of deep lead groundwater aquifers.  The revised Regional Waterway Management Strategys, currently under development, will be critical in guiding future direction in response to the State Government’s new policies as outlined in the Victorian Waterway Management Strategy

There is a range of Federal and State treaties, conventions, initiatives, legislation, policies and strategies that direct the management of rivers, floodplains and wetlands. Those of particular relevance include the Commonwealth Water Act 2007 and EPBC Act 1999, State Water Act 1989 and Northern Region Sustainable Water Strategy (DSE 2009), with a full listing found in Appendix one and two of the full RCS.

Important international treaties, conventions and initiatives that direct management:
• China Australia Migratory Birds Agreement 1986.
• Republic of Korea Australia Migratory Birds Agreement 2002.
• Japan Australia Migratory Birds Agreement 1974.
• Convention on the Conservation of Migratory Species of Wild Animals (Bonn Convention) 1979.
• The Ramsar Convention on Wetlands 1971.

Asset identification and prioritisation

The Aquatic Value Identification and Risk Assessment (AVIRA) system has been used to inform development of the next iteration of Regional River Health Strategies and this includes the identification of priority river reaches and wetlands as listed in tables 3.4 and 3.5. AVIRA builds on the River Value and Environmental Risk System (RiVERS). RiVERS is an asset inventory, which documents the environmental, social and economic values and threats associated with river reaches across Victoria. RiVERS was used to help develop the first round of Regional River Health Strategy (RRHS). AVIRA uses quantitative information where possible; otherwise asset identification is done by Goulburn Broken CMA technical staff. AVIRA values and threats process are documented in Peters (2009). Importantly AVIRA includes social and economic metrics.  AVIRA covers river reaches and wetlands.

 Table 3.4. Priority waterways and their significance.

Waterway

Significance

Goulburn Basin

Goulburn River

The river has many environmental, social and economic values. It is a Heritage River and is association with wetlands of national significance and contains an ecologically healthy reach. It supports many threatened species including Murray cod, Silver perch, Macquarie perch, Barred galaxias, Spotted tree frog and Alpine bent. It contains many important cultural heritage sites, provide water for agriculture and urban centres within and downstream of the basin, and supports a variety of recreational activities such as fishing and boating.

Seven Creeks

The waterway supports the threatened Trout cod and Macquarie perch.

Seven Creeks

The waterway supports the threatened Macquarie perch.

Gobarup Creek

Association with wetlands of national significance.

Hughes Creek

The waterway supports the threatened Macquarie perch and Murray cod.

King Parrot Creek

The waterway supports the threatened Macquarie perch.

Yea River

The waterway supports the threatened Macquarie perch.

Acheron River

Environmental Site of Significance.

Taggerty River

The river contains ecologically healthy and representative reaches and supports the threatened Barred galaxias.

Rubicon River

The waterway supports the threatened Barred galaxias.

Big River

It is a Heritage River, contains ecologically healthy and representative reaches, and supports the threatened Spotted tree frog.

Howqua River

It is a Heritage River and has high economic values.

Delatite River

It has high economic values and supports the threatened Murray cod.

Broken Basin

Broken River

The river is association with wetlands of national significance and supports the threatened Murray cod, Macquarie perch and Silver perch.

Holland Creek

The creek supports the threatened Macquarie perch.

Ryans Creek

The creek contains ecologically healthy and representative reaches.

Broken Creek

The creek supports the threatened Murray cod and is association with wetlands of international (Ramsar) and national significance.

Table 3.5. Priority waterways and their significance.

Wetland(s)

Area (ha)

Significance

Description

Barmah Forest

29,500

Ramsar listed

TLM Icon Site

Along with the adjoining Millewa forest in NSW, it forms the largest river red gum forest in the world. One of Victoria’s largest waterbird breeding areas. Protects 38 rare or threatened plant species.

Kanyapella Basin

2,581

DIWA listed

Mixed river red gum forest and black box woodland. Protects the nationally threatened River Swamp Wallaby Grass. Provides flood retardation. Important waterbird breeding area.

Muckatah Depression

2,909

DIWA listed

A long (over 60 km) and narrow prior stream depression connecting larger wetlands. It protects a number of threatened plant species and provides important habitat for waterbirds including the threatened Brolga.

Central Highlands Peatlands

33

DIWA listed

Five separate Sphagnum moss dominated bogs located along rivers and gullies in the Central Highlands surrounded by wet to dry sclerophyll forest.

Gaynor Swamp

300

DIWA listed

A large red gum lignum swamp that supports tens of thousands of water birds including migratory species.

Wanalta Wetland Complex

1,572

DIWA listed

Bioregional

Four hydrologically connected wetlands. Valued for their size, rarity, species diversity and waterbird habitat, including breeding habitat for the threatened Brolga. Can receive environmental water via the Wanalta creek and irrigation infrastructure.

Doctors Swamp

200

Bioregional

One of the most intact red gum swamps in Victoria. Supports a diverse number of species including 73 wetlands flora species and 44 wetland fauna species. Can receive environmental water via irrigation infrastructure.

Reedy Swamp

130

DIWA listed

(part of the lower Goulburn listing)

Supports thousands of waterbirds. It is a significant breeding area for colonial nesting waterbirds including the threatened Royal Spoonbill. Can receive environmental water via irrigation infrastructure and provides important drought refuge.

Kinnairds Swamp

96

Regional

A red gum swamp that protects the largest known population of the nationally threatened rigid water milfoil in Victoria. It provides important breeding habitat for waterbirds including the threatened Royal Spoonbill. The wetland is a popular recreational site for local and regional community members. Can receive environmental water via irrigation infrastructure.

Black Swamp

16.5

Bioregional

A small red gum swamp that protects the nationally threatened River Swamp Wallaby Grass and Australasian Bittern. It can receive environmental water via the Nine Mile Creek and irrigation infrastructure.

Moodies Swamp

180

DIWA listed

(part of the Broken Creek listing)

A large cane grass wetland that provides important habitat for waterbirds including the threatened Brolga and Eastern Great Egret. It protects the nationally threatened rigid water milfoil and can receive environmental water via the Broken Creek and irrigation infrastructure.

Winton Wetlands

8,750

Bioregional

The largest wetland restoration project in the southern hemisphere. The wetland complex provides important habitat for a large number of waterbird species including the migratory Lathams Snipe and protects seven nationally threatened flora species.

Alpine bogs

54

National

Areas that protect the nationally endangered Alpine Sphagnum Bogs and Associated fens ecological community. Found in small pockets across alpine, subalpine and montane areas in the south of the region.

Stockyard Plains

225

Bioregional

A cane grass dominated wetland that provides important breeding habitat for the threatened Brolga. The wetland is a mix of public and private land and can receive environmental water via irrigation infrastructure.

Tahbilk Lagoon

280

Bioregional

A large billabong connected to the Goulburn River near Nagambie. The wetland is a biological hot spot that protects a number of threatened species including the broad-shell turtle, the most southerly remnant freshwater catfish population in Victoria and the largest known watershield (native waterlily) population in Victoria. The water is managed by G-MW and the majority of the surrounding freehold land has been owned and managed by Tahbilk Winery for over 100 years.

Carlands Swamp

68

DIWA listed

(part of the Broken Creek listing)

On private land the wetland is the most eastern tangled lignum swamp in Victoria.

Lades spring wetland

<1

Regional

A rare button grass dominated spring wetland on private property in the Highlands. Pollen cores indicate the wetland is over 1000 years old. Recent investigations have found this and other spring wetlands in the area support culturally significant Aboriginal artefacts.

Yea Wetlands

6

Regional

Protects the nationally and internationally threatened hemiphlebia damselfly (living fossil). The wetland is also an important local and regional recreational and educational resource.

Horeshoe Lagoon

20

Bioregional

A billbong on the mid Goulburn River. One of only few wetlands in the region in excellent condition.