Lower Murray and Lakes Region

 

The Lower Murray and Lakes Region comprises the southern end of the Murray Darling Basin from Mannum to the coast. The two main water pipelines, which supply up to 90% of Adelaide's water in dry years, are located between Mannum and Murray Bridge in the northern part of the region and the intake for the water supply for the SE is at Tailem Bend. The quality of the water in this region is therefore of critical importance to South Australia.

The region accounts for 22% of dairy farms in the State and around 20% of the total milk production.  The two major processors in the state, National Foods and Dairy Farmers, have cheese factories located in this region, the former in Murray Bridge and the later at Jervois.  There has been changes in the milk output from this region due to the rehabilitation of the Murray River, however there are now some excellent opportunity for expansion and new investment into this region.

The Murraylands Regional Development Board has further information on this region.

The Lower Murray Irrigation Area and Lower Lakes constitute two different environments and are described separately below.

 

Lower Murray Irrigation Area

There are 27 reclaimed swamp areas on the former floodplain if the River Murray between Mannum and Wellington, known collectively as the Lower Murray Reclaimed Irrigation Area (LMRIA).  Most of this land was developed for agriculture between 1880 and 1940. A levee bank was constructed along the river's edge to control flooding.  Since the completion of the barrages at the Murray mouth in 1940, the reclaimed area are 1.0 to 1.5m below the river level, allowing water to be gravity fed for irrigation through sluices and syphons.  There is currently irrigated pasture on 24 of the swamps, three swamps are no longer irrigated.  Some irrigators also pump water from either the river, back channels of drainage channels to irrigate high land for pasture and fodder.

Currently there are 58 dairy farms, covering an area of 5200 hectares of swamps and approximately 1700 hectares of high lands.  The farms are irrigated through 250 inlet structures.  In about two thirds of the swamps of the LMRIA, the irrigation and drainage infrastructure is government owned and managed, with the remainder privately owned.  The State Government is funding a major rehabilitation and restructuring program in the LMRIA ti improve the water quality in the River Murray and to implement environmentally sustainable farming practises.  Most swamps in government ownership are being converted to irrigator managed trusts, with the trusts responsible for maintaining the irrigation and drainage infrastructure.  Approximately 100 hectares of land will be retired due to exit packages offered by the government rehabilitation project.

The LMRIA region produces approximately 85 million litres of milk.

 

Lower Lakes

The dairy industry on the Lower Lakes consists of the irrigated area between Narrung and Meningie and the dryland dairies south and east of Meningie. The district as a whole experiences hot dry summers and mild, wet winters.

Average annual rainfall in the Narrung and Meningie area ranges from 400-500mm (Australian Bureau of Meteorology). Rainfall occurs predominantly during the winter season, with 70% falling from April to October. The "seasonal break" can vary from March to June, with the average being around the second week of May. Average annual evaporation ranges from 1500-1800mm.

The district is largely a coastal plain with overlying calcareous coastal dunes. These dunes trend north-west and south-east and are usually between 10-30m above sea level. Most sands are slightly acidic in the surface to neutral or slightly alkaline at depth.

Because of the permeable nature of the mostly sandy soils, there is very little surface drainage throughout most of the area. Groundwater in the region is part of the groundwater system of the Murray Darling Basin. From the high rainfall areas in Western Victoria, groundwater moves slowly in a westerly direction. Discharge from the system occurs to the Lakes, the Coorong or low lying salinised areas. Salinity levels of the watertable reach levels of up to 3000mg/l in the confined aquifers and are generally unsuitable for irrigation.

Large areas of the Narrung Peninsula are irrigated from the Lower Lakes for fodder crops and pasture for use in dairy production. Algal blooms do occur in the Lower Lakes and can affect the quality of stock water.

 

Reference:

DairySA Regional Action Plan 2000

• Soil, Water, Topography, Climate
  
• Feed Systems
  
• Regional Contacts 
  

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Lower Murray and Lakes Soils, Topography, Climate, Rainfall & Water Sources

 

Detailed district plans outlines land descriptions (soil, water, rainfall, climate etc), land management issues and land management strategies for each district.

This link will take you to the South Australia State map. Click on your area of interest to download district information on soils, climate, water etc. http://soil.pir.sa.gov.au/html/nav_dist.htm

District information maps for this area include

• Coorong Land Management District Plan - http://soil.pir.sa.gov.au/html/coo_rep.htm
  
• Murray Plains Land Management District Plan
  

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Lower Murray and Lakes Forage and Feeding Systems

 

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 Lower Murray and Lakes Regional Contacts

 

Organisations	Contact	Telephone	Email
Murraylands Regional Development Board	Brenton Lewis	08 8535 7170	ceomrdbi@lm.net.au
PIRSA/Rural Solutions Murray Bridge		08 8535 6400
Dept Water, Land & Biodiversity		08 8531 1420
Environmental Protection Agency		08 8539 2112