Climate and Irrigation

Around two thirds of Tasmanian dairy farms are irrigated. In the higher rainfall areas in the far north west and on King Island the proportion of irrigated farms is less than 50 per cent. There is also a significant proportion of farms in the Deloraine area that are not irrigated.

Farm Irrigation

Tasmanian dairy farmers are increasingly using irrigation to supplement rainfall and maintain pasture production through summer and early autumn. Mostly this is based on farm schemes utilising winter storage or direct take from rivers. And in some areas such as the Circular Head, groundwater also contributes to the total supply.

Overall, around two thirds of Tasmanian dairy farms use at least some irrigation. In the higher rainfall areas in the far North West and on King Island the proportion is less than 50 per cent.

Irrigation Water Requirements

Irrigation water requirements depend on soil type, climate, soil fertility and pasture species. The estimated annual irrigation requirements for well managed perennial ryegrass dairy pastures are shown in the table below. Irrigation of well managed dairy pasture with high soil fertility is likely to increase pasture utilisation by 3-4 t DM/ha/yr and this will typically require around 4 ML/ha/yr of water to be applied.

Indicative irrigation requirements

Region Location Irrigation requirement (ML/ha/year)
North West Currie (King Is) 4.0
  Woolnorth 3.9
  Redpa 2.7
  Smithton 3.0
  Mawbanna 2.6
  Wynyard 3.9
  Burnie 4.6
  Sheffield 4.2
North Mole Creek 4.1
  Deloriane 4.7
  Cressy 5.3
  Lilydale 4.5
  Scottsdale 4.1
  Ringarooma 3.5
South Bushy Park 4.8

Source: tasdairyprojects website, Tasmanian Regional Pasture Growth Rates Tool

Irrigation Water Availability

The total area under irrigation in Tasmania has risen from around 40,000 hectares in 1985 to around 105,000 hectares currently, with an increase in irrigated dairying being one of the main reasons for the overall increase. Irrigated pasture (mainly for dairy farming) makes up 50 to 55 per cent of the total area irrigated in the state and around 60 per cent of total irrigation water used.

The total licensed water allocation for irrigation in Tasmania has increased greatly over the past 20 years. Most of that increase has been in the form of water taken into on-farm storage as distinct from direct take from rivers and streams.

Note: The large increase in "direct take" water between 2001 and 2005 was largely associated with the release by Hydro Tasmania of 30,000 ML of low surety (Surety6) water for irrigation.

The Water Management Act 1999 provides for the preparation of catchment water management plans, which are currently being progressed. These provide for environmental flow, and are a vehicle for integrating the priorities for use of water on a catchment scale. The Act also allows for the transferability of water licences separate from the transfer of land.

Average Dryland Pasture Growth Rates

Source: DPIPWE Water Management Branch

The Department of Primary Industries Parks Water and Environment (DPIPWE) has developed guidelines for the issuing of new water allocations into storage during the winter. There is a moratorium on the issue of licences for direct-take from rivers and streams during the summer.

Irrigation Schemes

In addition to on-farm irrigation schemes there are six large scale Tasmanian Irrigation district schemes operating in the State, a further four are under construction, five are operating that pre-existed before TI was established in 2008 and five schemes are in the pipeline if Federal funding can be secured.

Pre-Existing Schemes

Irregation Scheme Location Total Supply Enterprises Managed By
Meander Valley Irrigation Scheme (MVIS) Central North
Greater Meander Irrigation District includes Caveside, Rubicon, Quamby-Omaston and Hagley Schemes
43,000 ML Dairy, cropping, livestock finishing Tasmanian Irrigation
Cressy Longford Irrigation Scheme (CLIS) Central North
Cressy, Longford
10,000 ML Cropping, livestock finishing, some dairy Self Managed
Winnaleah North East
3,254 ML Dairy, livestock finishing, cropping Self Managed
South East Stage 1 & 2 South East
Campania, Colebrook, Richmond, Cambridge
4,300 ML Cropping including perennial horticulture Tasmanian Irrigation
Total   60,554 ML    

New Operational Schemes

Irregation Scheme Location Total Supply Enterprises Managed By
Sassafras Wesley Vale Irrigation Scheme North West
Sassafras, Moriarty, Wesley Vale
5,460 ML Poppies, cereals, pyrethrum, potatoes and vegetables (processed and fresh) Tasmanian Irrigation
Great Forester Irrigation Scheme (Formerly Headquarters Road) North East
South Springfield, Springfield, Scottsdale, North-Scottsdale and Waterhouse
1,980 ML Dairy, potatoes, vegetables (processed and fresh) and livestock finishing Tasmanian Irrigation
Winnaleah Augmentation (WISA) North East
Winnaleah, Derby, Branxholm
3,700 ML Dairy, livestock, finishing, cropping Tasmanian Irrigation
Whitemore Irrigation Scheme (WIS) Central North
Whitemore, Oaks, Bracknell, Liffey, Glenore
5,500 ML Poppies, cereals, pasture seed, potatoes, vegetables (processed and fresh) and pasture for livestock finishing Tasmanian Irrigation
Lower South Esk Irrigation Scheme (LSIS) Northern Midlands
Conara, Epping Forest, Perth, Longford
5,298 ML Cropping, livestock finishing, dairy conversions Tasmanian Irrigation
Kindred North Motton Irrigation Scheme (KNMIS) North West
Forth, Kindred, Abbotsham, Clerkes Plains, Sprent, Gawler, North Motton
2,500 ML Potatoes, vegetables (processed and fresh), poppies, cereals, pyrethrum, berries and dairy Tasmanian Irrigation
Midlands Water Scheme (MWS) Midlands
Campbell Town, Ross, Tunbridge, Oatlands, Mt Seymour, Jericho and Kempton
38,500 ML Poppies, cereals, canola, pasture seeds, lucerne, potatoes, pasture for livestock finishing with potential for dairy conversions and perennial horticulture such as grapes Tasmanian Irrigation
Upper Ringarooma Irrigation Scheme (URIS) North East
Scottsdale, Ringarooma, Legerwood, Bridport, Waterhouse
5,700 ML Cropping, livestock finishing, dairy conversions Tasmanian Irrigation

Schemes Under Construction

Irregation Scheme Location Total Supply Enterprises Managed By
South East Irrigation Scheme Stage 3 (SEIS3) South East
Tea Tree, Campania, Orielton, Pawleena, Penna, Sorell and Forcett
3,000 ML Cherries, apples, salad vegetables, wine grapes, apricots, olives and walnuts Tasmanian Irrigation
Dial Blythe Irrigation Scheme North West
Penguin, West Pine, Riana, South Riana
2,855 ML Dairy, cropping Tasmanian Irrigation

Proposed Tranche Two Schemes

Irregation Scheme Location Total Supply Enterprises Managed By
Scottsdale Irrigation Scheme (SIS) North East
Scottsdale, Briport, Waterhouse
8,600 Pastures, mainly dairy and some livestock finishing, with the remaining water used for cropping (potatoes, poppies and fresh vegetables) Tasmanian Irrigation
Southern Highlands Irrigation Scheme Midlands
6,500 ML Cropping, livestock finishing Tasmanian Irrigation
Swan Valley Irrigation Scheme (SWAN) East Coast
2,500 ML Perennial horticultural enterprises Tasmanian Irrigation
Circular Head Irrigation Scheme (CHIS) Circular Head
Togari, Woolnorth, Montagu, Edith Creek, Roger River, Mella, Forest, Irishtown
20,000 ML Over 90% dairy, cropping Tasmanian Irrigation
North Esk Irrigation Scheme North Esk
Evandale, White Hills and Relbia
3,000 ML   Tasmanian Irrigation

Irrigation Schemes Overview March 2004

Irrigation Schemes Overview