Lachlan River
Water Quality and River Flow Objectives

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This section gives the Water Quality Objectives (WQOs) and the River Flow Objectives (RFOs) for the Lachlan River catchment, which should be used to develop plans and actions affecting water quality and river health. Only the priority RFOs are listed in this section, but the remaining objectives still need to be considered when developing flow management plans or dealing with particular local river conditions.

Town water supply subcatchments

The streams in town water supply subcatchments typically feed into a town's water supply storage. In many cases, the catchment may be declared specially protected to minimise the effects of land use on water quality.

Map: This category applies to streams running through areas coloured light blue on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Drinking water-Disinfection only

Drinking water-Clarification and disinfection

Drinking water-Groundwater

Top of PageRiver Flow Objectives

Protect pools in dry times

Protect natural low flows

Manage groundwater for ecosystems

Minimise effects of weirs and other structures

Supporting information

Mainly forested areas

Streams in mainly forested areas are often valued for their conservation or recreational values. They often have relatively natural flows and water quality. Many are in national parks or state forests. Others are generally in the upper parts of catchments.

Map: This category applies to streams running through areas coloured green on the map (state forests, national parks and nature reserves). It also applies to other forested areas if any are defined locally.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Secondary contact recreation

Primary contact recreation

Aquatic foods (cooked)

Top of PageRiver Flow Objectives

Protect pools in dry times

Protect natural low flows

Maintain natural flow variability

Manage groundwater for ecosystems

Minimise effects of weirs and other structures

Supporting information

Waterways affected by urban development

Waterways within urban areas are frequently substantially modified and generally carry poor-quality stormwater. Local communities are often keen to see these waterways returned to more natural conditions.

Map: These areas are shown as orange dots on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Secondary contact recreation, as a short-term objective, within 5-10 years

Primary contact recreation: assess opportunities to achieve as a longer term objective, 10 years or more

Top of PageRiver Flow Objectives

Protect pools in dry times

Protect natural low flows

Mimic natural drying in temporary waterways

Maintain natural flow variability

Maintain natural rates of change in water levels

Minimise effects of weirs and other structures

Supporting information

Waterways affected by irrigation drainage

These are often natural watercourses whose flow is now dominated for substantial periods by irrigation drainage. Flow and water quality are therefore unnatural.

Map: These waterways are shown as green lines on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Other objectives may be needed to meet water uses within these systems and downstream.

Top of PageRiver Flow Objectives

Maintain wetland and floodplain inundation

Mimic natural drying in temporary waterways (including wetlands)

Maintain natural flow variability

Manage groundwater for ecosystems

Minimise effects of weirs and other structures

Supporting information

Uncontrolled streams

This category covers uncontrolled waterways that are not in the other categories. Their flow patterns are largely natural.

Map: These streams are shown as blue lines on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Secondary contact recreation

Primary contact recreation

Livestock water supply

Irrigation water supply

Homestead water supply

Drinking water at point of supply-Disinfection only

Drinking water at point of supply-Clarification and disinfection

Aquatic foods (cooked)

Top of PageRiver Flow Objectives

Protect pools in dry times

Protect natural low flows

Protect important rises in water levels

Maintain wetland and floodplain inundation

Manage groundwater for ecosystems

Minimise effects of weirs and other structures

Supporting information

Major regulated rivers

These rivers have large dams supplying irrigation water (and usually town and industrial water) for substantial distances downstream. Flows are typically supplemented during the irrigation season resulting in fairly stable and unnaturally high water levels. River flow is substantially reduced during non- or low-irrigation seasons. At any time of year in periods which would normally have high or very high flow, flows may be substantially reduced by the trapping of water in a large dam.

Map: These rivers are shown as yellow lines on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Secondary contact recreation

Primary contact recreation

Livestock water supply

Irrigation water supply

Homestead water supply

Drinking water at point of supply-Disinfection only

Drinking water at point of supply-Clarification and disinfection

Drinking water at point of supply-Groundwater

Aquatic foods (cooked)

Top of PageRiver Flow Objectives

No RFOs were recommended in 1999 as flow rules were in place. A Water Sharing Plan has been in place since 2004.

Supporting information

Controlled rivers with reduced flows-Willandra Creek system

This category covers river reaches downstream of the regulated sections, where the released water is extracted or diverted. In these cases, flows can be substantially reduced throughout the year, though special environmental releases may be possible. These rivers often have persistent low flows. Water quality can be affected by the loss of diluting or flushing flows.

Map: These rivers are shown as red lines on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Secondary contact recreation

Primary contact recreation

Livestock water supply

Irrigation water supply

Homestead water supply

Drinking water at point of supply-Disinfection only

Drinking water at point of supply-Clarification and disinfection

Drinking water at point of supply-Groundwater

Aquatic foods (cooked)

Top of PageRiver Flow Objectives

Protect pools in dry times

Protect natural low flows

Protect important rises in water levels

Maintain wetland and floodplain inundation

Mimic natural drying in temporary waterways (and wetlands)

Maintain natural flow variability

Minimise effects of weirs and other structures

Make water available for unforeseen events

Supporting information

Controlled rivers with reduced flows-Muggabah, Merrimajeel, Merrowie and other creeks in the Booligal region

This category covers river reaches downstream of the regulated sections, where the released water is extracted or diverted. In these cases, flows can be substantially reduced throughout the year, though special environmental releases may be possible. These rivers often have persistent low flows. Water quality can be affected by the loss of diluting or flushing flows.

Map: These rivers are shown as red lines on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Secondary contact recreation

Primary contact recreation

Livestock water supply

Irrigation water supply

Homestead water supply

Aquatic foods (cooked)

Top of PageRiver Flow Objectives

Protect pools in dry times

Protect natural low flows

Protect important rises in water levels

Maintain wetland and floodplain inundation

Maintain natural flow variability

Minimise effects of weirs and other structures

Make water available for unforeseen events

Supporting information

Controlled rivers with reduced flows-Great Cumbung Swamp

This category covers river reaches downstream of the regulated sections, where the released water is extracted or diverted. In these cases, flows can be substantially reduced throughout the year, though special environmental releases may be possible. These rivers often have persistent low flows. Water quality can be affected by the loss of diluting or flushing flows.

Map: These rivers are shown as red lines on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Secondary contact recreation

Primary contact recreation

Livestock water supply

Irrigation water supply

Homestead water supply

Aquatic foods (cooked)

Top of PageRiver Flow Objectives

Protect pools in dry times

Protect natural low flows

Protect important rises in water levels

Maintain wetland and floodplain inundation

Mimic natural drying in temporary waterways (and wetlands)

Maintain natural flow variability

Manage groundwater for ecosystems

Minimise effects of weirs and other structures

Make water available for unforeseen events

Supporting information

Controlled rivers with altered flow patterns

In these rivers, the average volume of flow is close to natural, but patterns of flow are altered. Water is released in a pattern to suit downstream stock and domestic demands.

Map: These rivers are marked in brown on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Secondary contact recreation

Primary contact recreation

Livestock water supply

Irrigation water supply

Homestead water supply

Drinking water at point of supply-Disinfection only

Drinking water at point of supply-Clarification and disinfection

Drinking water at point of supply-Groundwater

Aquatic foods (cooked)

Top of PageRiver Flow Objectives

Protect pools in dry times

Protect natural low flows

Mimic natural drying in temporary waterways

Maintain natural flow variability

Minimise effects of weirs and other structures

Supporting information

Artificial channels

This applies to entirely artificial watercourses constructed to supply water for irrigation or other purposes.

Map: Channels are marked in grey on the map.

Top of PageWater Quality Objectives

Protection of:

Aquatic ecosystems

Visual amenity

Top of PageRiver Flow Objectives

No RFOs are recommended for artificial watercourses.

Supporting information

This page was published 1 May 2006

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